Forecasters are warning that the ongoing El Niño is likely to become supercharged in the coming months and inject potentially unprecedented heat into our already warming world.

El Niño is the warm phase of a multiyear natural climate pattern, but models suggest this year's cycle will be exceptionally intense. Super El Niño conditions could contribute to temperature extremes until next year, but scientists are warning that it may also pose longer-term threats.

Jong-Seong Kug, a professor in the Department of Earth and Environmental Sciences at Seoul National University in South Korea, uses observational data and artificial intelligence to model El Niño events.

Kug has found that super El Niño events can drive sudden, dramatic and even irreversible climate regime shifts. Live Science spoke with Kug to learn more about climate regime shifts and the long-term threats posed by this year's ongoing El Niño.

Patrick Pester: Last year, you published a study that found super El Niño events significantly increase the likelihood of potentially irreversible climate regime shifts. With a super El Niño now looking very likely, how concerned should we be?

Jong-Seong Kug: We should be concerned but not alarmist, because our study does not suggest that every super El Niño inevitably causes a climate regime shift. Rather, a super El Niño can push an already-stressed climate ecosystem across a critical threshold. If a system is near a critical threshold, then strong forcing can induce irreversible change.

Current forecasts indicate a very strong El Niño is increasingly likely later this year. We need to watch vulnerable regions closely, particularly those that are already experiencing severe warming, drying, ecosystem degradation or ocean stress.

PP: What kind of climate regime shift do you fear most?

J-S K: I am particularly concerned about the persistent shift in major ecosystems, such as the Amazon rainforest moving toward a much drier and degraded state. You know, a long time ago the Amazon was a savannah area, so we are now approaching this kind of tipping point. Also, in the Amazon, this drying can weaken [or] even reverse the forest's role as a carbon sink.

The Amazon is a carbon sink, but imagine it becomes drier and drier, and there's some die-back of the forest. Now, [carbon] sink becomes source. This could amplify global warming long after an El Niño event.

PP: Is there anything we can do to mitigate the threat of extreme climate and weather events in the coming months?

J-S K: We cannot stop El Niño. But we can greatly reduce its human impact or ecosystem impact. Governments should use precision forecasts to strengthen our heat health plan, water and food management and flood and wildfire preparedness. In the long term, a rapid reduction in greenhouse gas emissions remains essential because every additional degree of warming increases this possibility that an extreme natural event will trigger lasting damage.

PP: Do you think a reduction in greenhouse gas emissions is likely, given where we are now?

J-S K: I don't think so. It's very difficult.

PP: So, where does that leave us?

J-S K: I don't know. There are some additional techniques we may use at a critical point. Have you heard about climate engineering? Like stratospheric aerosol injection [reflecting solar radiation back into space]. If we cannot do anything, then we have to choose that kind of technology. I don't want this kind of situation, but maybe in the near future we have to decide.

There are two kinds of climate engineering. One is carbon mitigation, just direct air capture [taking carbon out of the atmosphere]. That is a safe way. The other is solar energy management. We can deflect more solar energy from the surface.

So, the easiest way is just to inject an aerosol into the stratosphere; then this aerosol reflects solar radiation, and then global temperatures will decrease. It's like a volcano: After a big eruption of a volcano, the global mean temperature drops by about 0.6 degrees [Celsius, or 1 degree Fahrenheit] because there is volcano aerosol [in the atmosphere]. Instead of volcano aerosol, artificially we can inject aerosol into the stratosphere. Then global temperature can easily decrease.

But there are many side effects. Some we already know, but some we don't know. Like climate inequality. If we artificially decrease temperatures, then some countries will have a drought or a flood. And then how will we compensate?

Obviously, if you want some kind of climate mitigation, we need a kind of consensus across the countries.

PP: Is there anything else you'd like to add that we haven't covered?

J-S K: This year, super El Niño is developing in an already exceptionally warm climate. We are already seeing widespread heat waves this year, so we cannot attribute every individual event to this El Niño. But El Niño will intensify toward the end of this year, so it is likely to further increase the risk of extreme events in many regions, so we need to prepare.

Editor's note: This interview has been edited and condensed for clarity.

Climate change's impacts are being felt everywhere, from health and food security to extreme weather, sea level rise and collapsing ecosystems. World leaders have been slow to adapt to the warnings, despite an ever-growing body of evidence showing the compounding risks of greenhouse gas emissions.

But despite fossil fuels remaining the world's primary source of energy and emissions continuing to rise, there are changes afoot.

In his book "Despite it All" (Granta, 2026), author and journalist Fred Pearce looks at the shifts that have taken place over the last 40 years, highlighting how far humanity has come in the green transition. He believes this progress gives us reason to hope that we can eventually overcome the challenges we face today.

Pearce spoke with Live Science about his book, which has been shortlisted for the 2026 Royal Society Trivedi Science Book Prize.

Hannah Osborne: There are a lot of positive environmental stories throughout the book, including those that aren't necessarily being told. Do you think that there is a growing appetite for positive climate news now? And will it help us?

Fred Pearce: I detect a kind of desire to be told something other than it's all hopeless and there's nothing we can do. Some people are therefore saying, "Well, what can I do?" And they're very sort of personal stories about how they can contribute. But also people who think more, if you like, strategically: What can the world do, what can governments do, what, how can we influence that?

I try not to write what I think people want to read. I try to write what I want to say. And it seems to me that we do so many things so badly, whether it's managing our resources or water or handling forests or the climate, or pollution or whatever. We do things so badly that there is a great deal of scope for doing things a lot better. So, we need optimists and we need pessimists. We need pessimists to point out the problems. We need optimists to come up with some solutions or suggest where [there are] half open doors that we can push open.

I wrote this book in that kind of spirit to say "Look, yes, things are bad, yes, I'm not denying that they're bad, but there's an awful lot that we can do about it and in some cases are doing about it." That then divides into whether we're talking about human activity, our technical solutions to climate change. Tech fixes are good, not bad, which is something that can be a hard sell in the environment community sometimes, so I want to stress that.

I went to the Earth Summit 30 years ago where they agreed [upon] the original climate change convention. Back then they said we [need to] prevent dangerous climate change, but they really didn't know much about how to do it. Wind turbines were just, you know, a few masts on a hill in California. Nobody was dealing much in solar power because it was just so expensive. It had been developed for powering satellites and electric cars. Nobody was talking about [it].

We have made quite a lot of progress and it's not fast enough and CO₂ emissions are stable, they're not going down. We need to do a hell of a lot more and we may have passed climate tipping points. I'm not denying any of that, but rather than throwing up our hands or saying it's hopeless, let's get on with the tech, let's also recognize that nature is very good at recovering. You destroy a forest, a rainforest, it doesn't mean that it's destroyed forever. It will, given the chance, come back if we give it room. So let's give forests room to recover.

In large parts of the world it's already happening — in Europe, even in North America. Agricultural land is being abandoned, and when it's abandoned nature comes back and not necessarily in the sort of ways that we might think. But nature does come back, stuff regrows. We can see how evolution is being kickstarted, if you like, by the chaos that we're creating. That's not to say we shouldn't stop creating the chaos, but we can see how nature recovers.

These are things that we can recognize and respond to; giving nature room to recover, rewilding projects, therefore I'm all in favor of [them]. We're not rewilding where we're trying to garden nature to get back to some sort of perfected past, a pristine system where we thought that everything was great — pre-industrial revolution or before Europeans arrived in North America or whatever it might be. But, we can give nature room to evolve and adapt and change. We can see that nature's doing that all the time, with or without climate change and with or without humans. Nature is constantly, if you like, remaking itself.

I'm not saying nature always comes back in ways that we approve of. Let's recognize the distinction between our sort of slightly romanticized idea of what nature should be and what nature actually is.

HO: You talk about rewilding and letting nature take its course, but how do humans fit in with this? Can we adapt our own perceptions of what nature is allowed and what's not?

FP: I think we can probably forget about what's allowed and what's not. Nature will do what it wants to do. We pride ourselves on our ability to garden nature in a way, or manage ecosystems. We're not really very good at it. Nature will very often take over and do what it wants to do.

Some of the world's biggest rewilding projects have gone quite badly wrong because we haven't quite thought it through. The one I'm thinking of really is the large project in the Netherlands where they're trying to sort of recreate ancient European ecosystems and they ended up with mass deaths of animals because their conception of the ecosystem didn't quite figure out. They then largely abandoned the project because they didn't like to see large numbers of animals dying.

A hardline rewilder would say let nature take its course. I see the case for that, and often I would support that, but we have our own sensibilities and our own concerns and we are living in a world where we are very much in charge of what's going on. So while I'm in favor of standing back and letting nature take its course, we have our own sensibilities, and it's not wrong for us to want to intervene sometimes.

HO: There's a chapter on human population and fertility rates, and how this is very much a climate change story as well. We're now seeing a lot of the rhetoric around this, and rights being stripped back and taken away. What's it like for you, having seen the changes from the UN International Conference on Population in Mexico in the 80s, to Cairo in the 90s to now?

FP: It's an extraordinary story. I've been working on these issues for 40 years now so I've seen a number of changes. Some of the changes I've seen are how technical fixes somehow became a reality when they seemed very distant a while ago.

But our perceptions change too on many things. We are, in many ways, more attuned to environmental issues now than we were 30 or 40 years ago. One of the big changes that I've seen is the notion of the population bomb, which for much of the 20th century was seen as the number one issue. People would say, "Well, there's no point in fixing the climate, there's no point in reducing our pollution because there are more and more people on the planet, and we're kind of doomed for that reason."

Well, it hasn't [happened]. When I went to my first international conference, which was the UN Population Conference in Mexico City in 1984, that was all the rage. They gave the UN Population prize to the mastermind of China's one child policy, which — in terms of human rights and what I would regard as acceptable human behavior — was dreadful. But such was the concern about population issues that they wanted to give a prize to the operator of that program.

A lot has changed. A feminist agenda, if I could put it that way, and I would say that approvingly, has taken over in reproductive politics. I saw it at a UN population conference in Cairo in 1994, 10 years after the Mexico event, that we need to assert reproductive rights. Many environmentalists said that's a cop out. It was all "it's feminist perspective, but it's dooming us."

Well, it didn't, because what we found was that by and large, women wanted to have smaller families because their children got to grow up. Medical improvements meant that you didn't have to have four or five children to secure the next generation. Two would usually do, sometimes you just wanted one. Women wanted to have lives outside the home. The population people seemed to be a bit surprised by that.

The environmental agenda was a very male-dominated one for a long time. So that came as a bit of a surprise, but the net result is that we've halved our fertility rates. They're more or less down to replacement levels [of reproduction] now globally.

I'm not just talking about Europe or North America. I'm talking about almost everywhere except Africa, and African levels have come down. Sometimes they're coming down to super low levels, so that people are now talking about not having enough babies and how we can encourage people to have babies. There are parts of the world where we're down to one child per woman and even a bit less.

My argument is that we need to carry on. Not take a sort of Elon Musk approach [or] send the women back to the home and [do] reproduction and that's what their job is. We need to complete the feminist revolution so that women have more rights, can make better choices, and indeed couples can make more and better choices about the family size that they want. We can arrange things so that it is possible to have children and a career, or make it easier to do that, and at that point probably reproduction levels will come back up.

What I'm really saying is that the agenda is now vastly different from what it was as recently as the 1980s and, and into the 1990s. The population bomb is being defused, to put it simply, there's a residual momentum effect which means that our numbers will carry on going up a bit. Sure, that creates strains on the planet, but we're not now talking about double the world population every 30 years, which is what was being talked about back in the mid 20th century. It's tailing off.

We now have, if you like, a consumption bomb more than a population bomb. The global issue is consumption in the rich world, and that's what's stressing the planet now — not too many babies in poor parts of the world.

HO: Inequality between the super rich and people in developing countries is becoming more and more stark. How do we bridge the gap to make sure there's a reasonable living standard for regular people without a huge cost to the environment?

FP: The truth is, and the numbers have been done by a number of different people, a reasonable standard of living for everybody on the planet is perfectly feasible without destroying the planet.

We need to do some things better, we need to have better technology, but for me, right up there with climate change is an issue of global inequality. When I was young, it was taken [that] inequalities were diminishing and it was taken almost as read that they would carry on diminishing, and a lot of aid policies were directed towards that. That's kind of disappeared since the sort of Reaganomics of the 1980s, all the changes in the finance system and perhaps the fall of the Berlin Wall, which meant that the sort of socialist or, or equality-based agendas collapsed politically.

We're now finding increased inequality, and that, it seems to me, is a threat to the lives of millions and billions of humans, but also to global stability and our ability perhaps to manage.

Serious global issues like climate change and many others are all undermined by the political stresses and economic stresses created by rising inequality. I see them going together.

It's also clear that it's important to level up, but also level down from the obscene riches that we see among a small number of individuals, who seem to be accumulating a greater share of the world's wealth, whether we're talking about dollars or natural resources.

HO: You have a whole chapter on renewables and how they're outpacing fossil fuels. They're the cheaper alternative. How do you see the political opposition to clean energy panning out over the next five to 10 years?

FP: It's fizzling out. It's a weird political backlash and yes, any big social trend or economic trend, they all have backlashes and it feels to me like this is it. What we see in the real world is that the U.S. — not just the U.S., but principally the U.S. — are in a state of near denial about climate and they're wanting to go back to fossil fuels.

In the rest of the world, if you look at it in terms of geopolitics of [the] U.S. versus China, then the U.S. is pushing this rather old agenda of fossil fuels, and China is absolutely going to reap the benefits in many, many ways in its drive towards renewables. China has been a really bad story in the past with its coal burning — and it's still building a few coal-fired power stations. But the really big story is how China has been principally responsible for bringing down the costs of renewable energy, particularly solar power.

You can now go to the most remote corners of rural Africa and you find people putting up their solar panels to recharge car batteries so that they can run their lights in the evening or whatever it is. And then you've got megacities operating using increasing amounts of solar power. India is getting on the bandwagon as well. It's got the fastest growing solar energy economy in the world.

In the real world, renewable [energy] is mostly cheaper than fossil fuels. It is also quicker to install, you don't have to build a huge power station, you can do it in bits and pieces, bolt bits on.

Yes, there are grid issues and they need to be addressed, and there are limits on operating. There are challenges, but renewables are just growing so fast, and it is growing so fast because it is so cheap.

And it's become so cheap, to put it very simply, because the Chinese 20 or 30 years ago decided this is what's going to happen. While everybody else was sort of talking about it and fussing about it and doing it in research labs, the Chinese kind of got to grips with it. I remember back in the 1990s talking about people who were going into China and coming back and telling me stories about how the Chinese are really serious about renewable energy. To be honest, I didn't quite believe them, but they were right, and 30 years on, the world is living with the benefits. That's true whether you're talking about Europe or rural Africa or big cities in Asia or wherever. It's coming.

There will be different solutions in different places and there are undoubtedly things that are harder to do than, you know, running our national grids on renewable energy, which is becoming really quite easy and something that everybody wants to do. The cement industries, fertilizers perhaps, some of these industries will take some more technical innovation. But it's happening, these are technical fixes that are working in the real world. Will we do it in time? Well, we're a bit late on the case, but we are on the case.

HO: We're now seeing a massive rise in AI data centers as well. Is this bad tech, shall we say?

FP: It's a serious issue. Partly because they're growing so fast — they can't just plug into the grid because the grid really can't deliver, so these companies are developing their own energy systems. Even in the U.S. they are very often renewable systems because they're cheaper. If you've got a data center out in Texas, then you're going to use wind power or solar power because it's cheaper and you're in control of it.

I suppose we reach a point where [we have to decide], do we want to reduce our use of energy or have almost as much energy as we want, but just green it and green it very fast. It is true that if all the renewable investment is going into electricity for data centers, that leaves less investment for other sectors of the economy, so I'm sure there are trade-offs, and I'm not saying that we should embrace data centers. But they can be a driving force for adoption of different forms of energy, renewable energy, and for perhaps changes in the grid systems as well.

I think we can have both. I think we need to have both because we're probably not going to stop the data engines, so we've got to find ways of greening them. There are issues and there are challenges ahead, and I don't want to diminish any of those, but you know, let's, let's be hopeful.

The title of the book uses the word hopeful rather than optimist because I don't want to sound Panglossian, but I do want to inject some hope.

HO: When you started writing the book, what did you hope people would take from it, and did that change after you'd finished?

FP: Well it kind of evolved. It began as an idea to sort of [be a] retrospective of my reporting, and then the publisher said, "Well, the story changes rather a lot along the way, so rather than just showcasing your reporting over 40 years, why don't you showcase the change, and be hopeful in the context of how things have changed over the last 40 years?"

That was [the] kind of starting point, and we sharpened up on it, as we went along it did become "Despite It All" and you know, the title is important, and not diminishing the "All." There's a lot of bad stuff out there, but despite it all we can have hope and we can find, develop and demand solutions.

HO: Did you find anything during the process of writing the book that surprised you?

FP: As I say, it started as a sort of retrospective project and going through it, [there were places I went years ago] and it did look bad, then I checked up on what had happened over the intervening years and suddenly things looked a lot better.

I went to Alaska and saw how the conflicts over managing caribou herds and the huge migrations that go on and it felt like that was doomed. I was talking to people who were hunting the animals and they were trying to protect them because they wanted to hunt them, therefore they wanted them still to be there, which is kind of counterintuitive for many environmentalists, but you know, they were the best defenders of the caribou because they ate them.

But it felt doomed, and yet 20 years later I checked out the numbers and the population of that herd has doubled and tripled. So stuff does happen and I suppose my surprise was how much good change I found when I looked into it further. Maybe that's me being better at looking for good news stories. I've written quite a lot of "bad news" books over the years and done a lot of "bad news" journalism over the years, so I certainly don't discount that. But if you step back and you think, well did good stuff happen? Well, yeah, sometimes it did.

The bison herds are coming back on the plains of parts of North America, if you go to Montana. The ranches are disappearing and big areas are being set aside for bison, and I've been seeing how farmland in parts of southern and eastern Europe has been abandoned over the years. It's not necessarily good news that we're abandoning farmland, but again, the way that nature comes back and woodlands are growing, there are more forests in Europe than there have been for probably centuries.

There's a lot of bad stuff to say. But it does seem to me that we have to not just cling onto, but embrace good stuff and try [to] take it forward.

Something I really hadn't thought about till I went back was what were the big issues in the 1980s, 1970s when I started out. Well, all our industrial rivers in Britain were filthy. Now our industrial rivers are relatively clean. It's our agricultural rivers that are filthy, so, I mean, there's been a big change there.

Nobody has to talk much about the ozone layer now. That was the number one issue in the mid 1980s, and the absolutely terrifying prospect if we hadn't fixed that. But it's been fixed.

We banned the chemicals that were doing it.

Remember acid rain, lead in petrol. They were hot topics, headline news, part of the rise of the environmental agenda in the 1980s — and they're the ones that we don't have to talk about anymore.

Now we're talking about climate change. I think there are other things coming up. I think the issue of nitrogen pollution is a fast growing one, and we need technical solutions to that.

The green revolution of crops, the high-yielding crops, which got us out of a cycle of ever worsening hunger and famines in the mid 20 century. That was a solution which created new problems. Those crops grew very well, but they required large amounts of inputs, including water, and water is now a growing issue — finding enough irrigation water, but also fertilizer and other agrichemicals. We're now reaping some of the bad effects of that, and we need to solve that. Scientists I know are working on, if you like, high-yielding crops that don't require so much fertilizer and don't require so much water.

It's doable because as I think I said at the start, we do a lot of things really very badly, but that does give us a lot of scope to do things a lot better, so let's get on with it.

This interview has been condensed and edited lightly for clarity.

Biodiversity loss has been recognized as a threat to global stability for decades. The decline in overall diversity of species on our planet, either through extinction or a fall in abundance, can culminate in ecosystem collapse.

But in this excerpt from "Despite it All" (Granta, 2026), author and journalist Fred Pearce looks at the remarkable resilience of nature. If we can put aside our notions of what should and shouldn't be in a given environment and leave nature to adapt and thrive, we may begin to see the gains needed to support a healthy biosphere.

"Despite it All" has been shortlisted for the 2026 Royal Society Trivedi Science Book Prize.

If we are serious about rewilding, then we need to accept that it will take its own course.

Often invasive species are just the first stage of an ecological resurgence. They are the first movers, and their infestations are short-lived. In time, diversity usually returns — even if it's not always the same diversity as was there before. We should recognize that. We need to be as adaptable as nature itself, and jettison our more romantic notions about biodiversity and pristine environments.

So do many oldschool ecologists, says Chris Thomas, an ecologist at the University of York. They too often simply ignore any bits of nature that do not meet their expectations of what "should" be present. "The establishment of successful species in new locations is commonly interpreted as further evidence that the Earth's system is departing from a more desirable state," he told me.

So when biodiversity assessments are conducted, "alien" species lurking in the undergrowth are simply not counted. As outsiders, they are deemed not to belong to the ecosystem they inhabit. Thomas says that, in Britain, official records show biodiversity in decline, even though, if we add all losses and all gains together, "it is unequivocally true that the total number of species in Britain is increasing."

Most of the gains — the weeds, pests and alien species — are kept off the biodiversity books. This amounts to an ecological catch-22. Biodiversity can only ever decrease, as new species are seen as inimical to the local environment, and each year millions of pounds, dollars and euros are being spent to eliminate them.

Of course, it sometimes makes practical sense to eradicate invaders. I don't say we shouldn't try to keep out pests that cause short-term ecological mayhem and economic damage. But if we choose to get rid of new species, we can't then hold up our hands in horror at declining biodiversity. And besides, ecologically as much as socially, migrants can stir things up to good effect. They interact with other species — eating or being eaten, pollinating, and rotting after death to nurture new organisms.

We should embrace novel ecosystems that contain both what we regard as native species and the feral, opportunistic interlopers that find their new environment congenial. In his book about weeds, British naturalist Richard Mabey celebrated what he called these "outlaw plants" and showed how they have had a hand in shaping not only our landscape but our civilization, becoming crops, medicines and sources of beauty and creative inspiration.

It is easy to be nostalgic about past ecosystems as a golden age. But what we imagine to be the perfect ecological state — a supposedly natural order of things that often gets called "the balance of nature" — was mostly itself a passing phase. Nature is always moving on. And more often than we realize, humans have had a hand in what we now like to regard as natural.

Environmental scientist Erle Ellis, who runs the Anthroecology Lab of the University of Maryland, argues persuasively that most of the planet has been heavily influenced by human activity for thousands of years, including places such as the Amazon that we often think of as untouched. We have, in effect, long lived on a "used planet," and humans and nature have not historically been at odds. The most biodiverse places are often those where people have lived the longest. By constantly tending the land, past civilizations created ever-changing mosaics of habitats where more species thrived than in places with less human interference.

So, we should be careful not to let our reverence for the pristine blind us to the environmental potential of today's wastelands, backwoods, abandoned fields, scrublands and no-go areas. In a Good Anthropocene we are likely to need more of them.

There is a final reason for believing that nature is equipped for recovery from almost anything we can throw at it. The apparent chaos of the Anthropocene is turbocharging evolution itself. Every perturbation of our environment creates an opportunity for existing species to adapt or for new ones to evolve, says Chris Thomas.

I first met Thomas in 2004, when he had just published an influential paper warning that climate change could wipe out a quarter of the world's species this century. He called it "terrifying." It was headline news. Two decades later, he has not changed that forecast, but he has added an important rider. Despite the coming extinction holocaust, he told me, "the Anthropocene could raise biological diversity."

His research is showing that evolution in the twenty-first century is speeding up to fill the gaps left by the extinctions — delivering new and better-adapted species. "The seeds of recovery are already visible," he told me. "Genes are jumping around. New species are beginning to emerge." Rob Dunn, an ecologist at North Carolina State University, agrees. In his book "A Natural History of the Future," he says that this evolutionary spurt is happening fastest in urban landscapes, where species are adapting to city life with almost as much alacrity as newly arrived humans.

This urban ecological renaissance resembles the story of the finches on the Galápagos archipelago, which Charles Darwin observed to have evolved different beaks to match the food on the different islands. In modern cities, house mice have evolved to produce saliva with a chemical make-up better able to digest the carbohydrates available in urban food; cockroaches and bedbugs have developed resistance to pesticides and even learned to avoid sugar-impregnated bait; London's pigeons have learned to commute on the Underground. We have clothes moths and carpet beetles.

Such natural innovations may not always be cuddly, but they do show that nature is on the prowl in the Anthropocene. So where is biodiversity headed? It is undeniable that most species of plants and animals are currently in numerical decline in a human-centric world.

This global disturbance is favouring some generalists — so-called superspecies — that can occupy a wide range of habitats, displacing local, rare and specialist species. Locally, however, biodiversity has sometimes increased substantially, especially in the rich kaleidoscopes of gardens, parks, toxic brownfield sites, roadside verges and so on that humanity has helped create.

Such places may become crucibles for a biodiversity rebound. Understanding this reality should change how we do conservation. We should not abandon nature to its fate. Some of our favourite species will pass into history unless we act to save them, and I'd vote for action any day. But it does mean embracing rather than rejecting the processes of change. Change in the Anthropocene is good. We should be grateful that nature is finding a way.

This is an extract from Despite it All by Fred Pearce, published by Granta.

While millions around the world grappled with extreme heat this month, a research station in Antarctica recorded Earth's coldest temperature since 2012.

The high-altitude research station, named Concordia, logged a low of minus 119.4 degrees Fahrenheit (minus 84.1 degrees Celsius) on July 18, according to data from the station.

Concordia is located in the interior of the Antarctic continent, which is currently in the dead of winter with no sunlight. Temperatures at the station regularly fall below minus 112 F (minus 80 C) this time of year ‪—‬ so the new reading isn't unprecedented, but it's still significant.

"Even here, where extreme cold is expected, temperatures below minus 84 C are remarkable and highlight how variable Antarctic weather can still be," Gabriele Carugati, the station leader at Concordia for Italy's National Antarctic Research Program (PNRA), told Live Science over a video call from the station.

The French Polar Institute Paul-Émile Victor, which runs Concordia with the PNRA, sent Live Science raw data from July 18, which showed the temperature dropping to minus 84.1 C twice, at 6:25 a.m. and 6:34 a.m. local time.

The extreme chill at Concordia stands in sharp contrast to the sweltering heat that many countries are currently experiencing. North America and Europe have been battling heat waves this summer, with Western Europe recording the hottest June on record. Meanwhile, wildfires are raging in Canada, the U.S., France, Spain and other countries.

Globally, average temperatures are going up as humans pump more heat-trapping greenhouse gases into the atmosphere. However, Earth's weather systems are complex, and climate change doesn't mean that everywhere gets hotter all of the time.

"Climate change describes the long-term global trends, while individual weather events can still [bring] exceptional cold," Carugati said. "Antarctica is influenced by complex atmospheric processes, so an extreme low temperature at one location does not contradict the broader picture of global warming."

"Astronauts of ice"

Concordia is considered the most remote and extreme research station in the world. Built on top of a 10,800-foot-thick (3,300 meters) ice cap, the station is used for a variety of purposes, including seismic observations, astronomy and the modeling of Earth's past climates, according to the French Polar Institute Paul-Émile Victor.

"Concordia is a special place because it sits at over 3,200 meters [10,500 feet] above sea level on the Antarctic Plateau, and more than 1,000 kilometers [600 miles] from the coast," Carugati said. "During winter, there is no sunlight for months, the atmosphere is extremely dry and stable, and under clear skies, heat continuously escapes to space because there are no clouds, allowing temperatures to fall to extraordinary levels."

Concordia's environment is so harsh and isolated that the station is also used to improve our understanding of the physical, mental and social challenges astronauts experience in space. Carugati noted that the only person at the station who is not researching the environment is a European Space Agency biomedical doctor, who is studying the researchers who work there, nicknamed "astronauts of ice."

Planes can't fly to Concordia once winter sets in, and it's around 370 miles (600 kilometers) from the nearest research station. That technically makes crews more isolated than astronauts on the International Space Station, which orbits about 250 miles (400 km) above Earth, according to the European Space Agency.

What is the coldest temperature ever recorded?

The coldest temperature ever recorded at Concordia was minus 120.5 F (minus 84.7 C), logged in the winter of 2010, according to the Italian Antarctic Meteo-Climatological Observatory. However, another high-altitude research station in East Antarctica has the all-time record for the coldest temperature ever recorded on Earth. Russia's Vostok weather station, the nearest station to Concordia, recorded a temp of minus 128.6 F (minus 89.2 C) in July 1983, according to the World Meteorological Organization.

Satellite data suggests that temperatures can drop as low as minus 144 F (98 C) in East Antarctica, according to a 2018 study published in the journal Geophysical Research Letters. However, even though Antarctica is the coldest and driest continent, it's not immune to global warming.

Major glaciers and the ice sheet they support are at risk in West Antarctica, with the Antarctic Peninsula — which extends out of the western side of the continent — experiencing the most rapid warming. A study published in February in the journal Frontiers in Environmental Science found that decisions made on greenhouse gas emissions today will determine how much the peninsula will change in the coming centuries, with sea ice, ice shelves and glaciers, along with the penguins that live on them, at risk of disappearing.

Concordia sits on the largest ice sheet on Earth. This sheet in East Antarctica is more stable than the smaller sheet of West Antarctica, but it is still vulnerable to rising temperatures. An unprecedented Antarctic winter heat wave in March 2024 saw temperatures near Concordia rise to a record high of 15.1 F (minus 9.4 C) ‪—‬ about 32 F (18 C) warmer than the previous March maximum. This East Antarctic heat wave was amplified by global warming, according to a study published in April in the journal npj Climate and Atmospheric Science.

Earth recently entered an El Niño, the warm phase of a multiyear natural climate pattern, which could bring unprecedented temperature extremes to an already-warming world. Carbon Brief, a U.K. based outlet that reports on climate news and policy, has predicted that 2026 is likely to be the second-warmest year on record, behind 2024, with the intensifying El Niño increasing the likelihood that 2027 will be the warmest year ever recorded.

For now, at Concordia, the researchers are continuing their work in the blistering cold of Antarctica's winter. Carugati noted that the latest extreme-temperature data will inform forecasts and long-term climate monitoring.

"Extreme observations like this help scientists better understand atmospheric processes and improve the climate models," he said.

Runoff from Greenland's rapidly melting ice sheet could severely disrupt currents in the Atlantic Ocean that regulate the global climate, researchers say. But the fresh water won't trigger the complete and irreversible collapse of the circulation that some research predicts, a new study suggests.

By 2100, Greenland meltwater could cause a reduction in the strength of the Atlantic Meridional Overturning Circulation (AMOC) equivalent to an additional 10% to 20% on top of the weakening that many scientists already expect for this huge system of currents, researchers found.

Previous research suggests the AMOC, which moves heat from the tropics to the Northern Hemisphere and cold water back south toward Antarctica, is at its weakest in more than 1,000 years due to Arctic ice melt and soaring ocean temperatures. Models indicate that the circulation will continue to weaken for decades to come, potentially unleashing freezing weather in Northwest Europe, additional sea-level rise along the U.S. East Coast and droughts around the equator.

The new study revealed that by 2300, Greenland's ice sheet could cause a whopping 40% of AMOC weakening on top of the declines projected by some climate models if we continue to cook the planet. The results highlight the effects on the AMOC of a growing freshwater pulse from Greenland that most climate models currently don't take into account, the authors said.

"By the year 2100, yes, we have something, but the greatest fraction is what we add later," study co-author Jost von Hardenberg, a professor in the Department of Environment, Land and Infrastructure Engineering at the Polytechnic University of Turin in Italy, told Live Science.

Meltwater from the Arctic and Greenland slows the AMOC by preventing the formation of deep currents in the North Atlantic that drive the circulation south toward Antarctica. Deep currents form when masses of cold, salty water sink to the seabed, but inputs of fresh water and rising water temperatures are blocking this step by diluting and warming surface waters.

While Arctic meltwater is commonly integrated into climate simulations, researchers have been slower to include runoff from the Greenland ice sheet in models, partly because this runoff may not be as disruptive as Arctic meltwater on shorter timescales, von Hardenberg said.

"In order to represent correctly the Greenland melt, you need a specific, dynamic model for the Greenland ice sheet. It's nice to have, but it requires a lot of resources to develop," von Hardenberg said

The Community Ice Sheet Model version 2 (CESM2) is one of the few available simulations of the Greenland ice sheet. For the study, von Hardenberg and his colleagues used a global climate model called EC-Earth3, which does not include the Greenland ice sheet. The team added the ice sheet from CESM2 to explore how it might affect the AMOC over the next few centuries. Adding the ice sheet separately enabled them to compare AMOC weakening with and without Greenland, clearly revealing the impact of the ice sheet on the AMOC's strength.

The results, published June 19 in the journal Science Advances, suggest the Greenland ice sheet will have a big influence on Atlantic ocean currents, especially after 2100.

"Greenland starts really melting strongly only after that date," von Hardenberg said. "If you go farther in our simulation — we go up to the year 2300 — that is also when this meltwater really becomes extremely strong."

Yet unlike other studies that show the AMOC collapsing irreversibly under climate change, in this model, the circulation recovered once the team switched off the meltwater or dialed down greenhouse gas emissions. Both the simulations that didn't include the Greenland ice sheet and those that did had similar results, recovering partially when the meltwater was turned off and fully when greenhouse gas emissions were stopped.

The recovery in the model suggests that the AMOC is more stable than previously thought and doesn't suddenly flip from an active state into a collapsed one, von Hardenberg said. "It's consistent with a strong weakening, but not a shutdown," he said.

Overall, the findings show that it is important to include the Greenland ice sheet in climate models — something von Hardenberg and his colleagues are planning to do in the next version of the EC-Earth3 model.

"It's really something which is worthwhile doing to better constrain the uncertainty of these future simulations," von Hardenberg said. "If we have a larger set of models which include this component, we will be in a better position to try to answer the question, 'How much do we expect AMOC to decrease in different scenarios?'"

Other experts agreed that integrating the Greenland ice sheet in climate models will increase the accuracy of AMOC predictions.

"What makes the study particularly interesting is that it directly tests a process that has often been highlighted as an important source of uncertainty in future AMOC projections," said Jonathan Baker, a senior climate scientist at the Met Office in the U.K. who was not involved in the study.

The results are consistent with previous research showing that Greenland meltwater causes additional AMOC weakening, but whether the system could collapse is still uncertain, given that the team used only one model, Baker told Live Science in an email. "Repeating these experiments across a wider range of models will be important to assess how robust the findings are," he said.

Nicholas Foukal, an assistant professor at the University of Georgia's Skidaway Institute of Oceanography who was not involved in the study, said he doesn't think the use of a single model limits the analysis.

"I think this result is robust and I am glad to see the authors come to this conclusion in such a high-resolution and realistic coupled climate model," Foukal told Live Science in an email. "This finding also agrees with other modeling results that require immense amounts of fresh water, much more fresh water than is available on Greenland, to cause irreversible change in the AMOC."

However, a third expert said the model used in the study is unrealistic, because its parameters make the AMOC more resilient than those of other models. Therefore, the study should be replicated in other models to draw unbiased conclusions.

"While the experiment reported is interesting, its outcomes are neither surprising nor should be interpreted as exemplary for the whole model ensemble," Sybren Drijfhout, a professor of physical oceanography at the University of Southampton in the U.K., told Live Science in an email.

Researchers should investigate the impact of the Greenland ice sheet on the AMOC further, von Hardenberg said. "It would be interesting in the future to check it [the AMOC's recovery with Greenland meltwater] with other models, but of course it's encouraging to see it in one case," he added.

Extreme coastal flooding events are occurring far more frequently in our warming world than ever before, threatening countless communities that will only become more vulnerable as climate change intensifies.

A recent study found that once-in-a-century flooding events now strike on our planet about once a decade. The study, published June 10 in the journal Nature Climate Change, also found that human-driven climate change has quadrupled the frequency of coastal sea level extremes since 1900.

The findings were released alongside another study by a separate team, published in the journal Science Advances, that found human-caused sea level rise was clearly measurable at 97% of sites sampled around the world, and was responsible for around 58% of the observed daily extreme water level exceedances between 2000 and 2018. In other words, human activities are the primary drivers behind sea level extremes — which include storm surges, high tides and rising sea level anomalies.

As the ocean's potential to devastate coastal communities surges, Live Science spoke with Sönke Dangendorf, lead author of the Nature Climate Change study, to learn more about what's to come. Here's what he had to say.

Patrick Pester: How do you separate human-driven sea level rise from natural forces?

Sönke Dangendorf: The absolute basis for doing these kinds of investigations is to work with observations, but observations are unfortunately sparse. We have a few more than 100 tide gauges [distributed worldwide] that offer long, century-scale records of sea level change since the early 20th century. We see that sea levels are changing at those locations, but we cannot tell a whole lot about what is happening elsewhere. So, what we can do is use the same climate models that we use to produce future projections of sea level change.

If you compare observations with the models, then the models need to be able to reproduce what the observations have shown. That was the first step we did, and indeed we proved in this study that the climate models are capable of reproducing observed climate. The nice thing with climate models then is that if you are able to reproduce what has been observed, you can start doing experiments. For instance, you can keep greenhouse gases constant in the modeling and then assess the influence of natural climate variability on the changes that we have observed. That's what we did in the study.

We found that we have seen already a 12-fold increase on average globally in what used to be a once-in-100-year event in 1900. And when we do these forcing experiments, we have also seen that anthropogenic forcing [human-driven change], in particular since the 1970s, has become the dominant force.

PP: What does this mean for coastal communities around the world?

SD: A couple of centimeters of sea level rise doesn't sound like a whole lot in theory, but if you live along the coast, it hits you much harder than you might think. Just an example: I used to live along the U.S. East Coast in Norfolk, Virginia. The community was built along the water, and they used to be fine in the 1950s and 1960s; they wouldn't see flooding at all, or maybe just once every five or six years. But due to sea level rise, what happens now is that high tide leads to flooding. You see flooded streets, and that affects your commute, so people increasingly cannot make it to work.

It affects your daily life suddenly. And then it makes it very hard for you and your coastal community because you have increasing insurance costs — the accumulated costs of these events can easily be as much as a major hurricane making landfall. So, this is a daily experience that many people already have, and it's a direct impact of sea level rise.

With respect to what we assessed in these more extreme events, people may absorb a once-in-a-100-year event once in their lifetime. They may experience something like a Storm Sandy, and they may be able to recover from that, but if you think about recovering from that basically every eight years — the frequency of these events nowadays compared to 1900 — that's of course way more difficult and not feasible for many people.

PP: What can we do?

SD: We can adapt. The silver lining here is that we have shown humans are the dominant forcing factor behind these changes. That's the silver lining because it means if we react, we can do something about it.

The reaction to changes in climate is often delayed, so we have sea level rise that we are already committed to. For instance, if you look into projections, they all agree with respect to what happens until around 2060, independently of how much greenhouse gases are emitted. There's no way around that. We could stop emitting greenhouse gases today, and we would still experience it. So, we need to adapt to that sea level rise, but if we mitigate climate change, if we stop emitting greenhouse gases, then we can avoid dangerous sea level rise, and that's very important.

PP: What will the world look like in 2060 with the committed sea level rise?

SD: According to the last IPCC [Intergovernmental Panel on Climate Change] report, what used to be a once-in-a-100-year event in the present day will occur annually at 19% to 31% of tide gauge locations by 2050. So, at about a quarter of the locations, you will experience these once-in-a-100-year events annually, and that is something that is just mind-blowing.

The changes are happening much quicker in low-latitude locations. The reason is that in the tropics you typically have a less variable climate. You don't have these massive swings all the time. For instance, in the North Sea, we have a storm season, and we have huge tide ranges. We are already adapted to pretty massive changes of multiple meters, so a couple of centimeters of sea level rise do not play out that hard, but in the tropics, where it's more calm, it makes a huge difference.

As an analogy, think about two hurdle runners. You have one hurdle runner that's compared to the tropics; he jumps very consistently but always below the hurdle, so he never makes it over. Then you have another hurdle runner that's the North Sea type of guy. His jumps are very variable. Sometimes he's very high and makes it over that hurdle, but very often he also jumps very low. Now think about lowering that hurdle, which is comparable to increasing sea levels. Suddenly, that hurdle runner who is very consistent makes it over all of the time, while the guy from the North Sea may jump over the hurdle a couple more times, but he also still has the very extreme lows. So, the constant jumper is way more sensitive to these changes.

Editor's note: This interview has been edited and condensed for clarity.

Tropical forests draw down and store large quantities of CO₂ from the atmosphere. The Amazon rainforest in South America, for example, stores approximately 123 billion tonnes of carbon — more than is stored in any other terrestrial ecosystem in the world. But these forests are facing a critical challenge.

Research from 2023, which was carried out by me and more than 100 colleagues, found that tropical forests in South America are vulnerable to climate extremes. We determined that during an El Niño event, the warm phase of a natural fluctuation in the Earth's climate system, South American tropical forests may fail to act as a carbon sink.

This finding becomes even more alarming when we consider the increasing frequency and intensity of El Niño events. There have been twice as many "very strong" El Niños in the last 60 years as there were in the 60 years before that. And the US National Oceanic and Atmospheric Administration has recently confirmed that such an El Niño is currently underway.

Tropical forests absorb CO₂ through the process of photosynthesis and convert it into biomass. However, the balance between photosynthesis and respiration is delicate and depends on two factors: temperature and water availability.

In hotter and drier conditions, plants close the pores of their leaves to avoid water loss. But closing them effectively cuts off a plant's fuel supply because it is through these pores they absorb CO₂. This starves plants of the carbon needed for photosynthesis and to grow.

During El Niño years, which are characterized by high temperature anomalies, prolonged climate stress leads to reduced forest growth and increased tree mortality. The effects of this are felt for decades as carbon is released back into the atmosphere when the dead trees decompose.

Our findings revealed that during the 2015-2016 El Niño, when temperatures on land were at least a degree higher on average than usual conditions, some of South America's tropical forests effectively stopped absorbing carbon. This raises concerns about the possible impact of the current El Niño on the Amazon and global climate.

In our research, we measured over half a million trees across six South American countries over a period of more than 30 years, using tape measures to track their growth. These trees belonged to over 4,000 different species. We used this data to calculate precise estimates of the amount of carbon stored as a forest's aboveground biomass.

We found that the vulnerability of these forests to El Niño conditions was closely linked to their baseline climate. While we tend to assume that rainforests are all hot, wet and biodiverse ecosystems, seasonal drought is a reality for many tropical forests. Conditions in regions at the edge of the Amazon rainforest, for example, tend to be particularly hot and dry.

Our findings revealed that drier forests at the edge of the Amazon, where trees regularly endure periods of limited water availability, were especially susceptible to extreme El Niño conditions. On average, a 0.5°C increase in temperature caused these forests to lose 0.5% of their aboveground carbon.

Larger trees suffered the most. While tree mortality rates increased from 1.8% to 3% per year during the El Niño in South American tropical forests as a whole, mortality rates effectively doubled for medium (classified as over 20cm in diameter) and large trees.

The fact that larger trees with less dense wood died at much higher rates compared to small trees and those with high wood density points strongly to hydraulic failure, when intense atmospheric moisture demand snaps the tension in the tree's internal water column rather than slow carbon starvation.

These results suggest that adaption to seasonal drought may not be sufficient to protect tropical forests from extreme events. Climate extremes are possibly already pushing forests at the edges of the Amazon beyond their capacity to adapt, causing catastrophic carbon losses.

A looming threat

Scientists have warned that 2026 may again be the warmest year on record. Heightening the alarm further is the severity of the current El Niño. Never before has an an El Niño begun when oceans are already so warm and air temperatures so high.

On top of this is the fact that, over the past three decades, the edges of the Amazon have experienced some of the highest temperatures and most rapid warming the tropics have ever seen. The structural integrity of a forest is compromised when a major climate anomaly occurs before it has recovered from recent, multi-year stress.

These compounding factors mean that we risk witnessing tree and carbon losses on scales not yet seen.

Tropical forests are invaluable assets in the fight against climate change. But South American tropical forests, a once-reliable carbon sink, are vulnerable to intensifying heat and drought. There is a risk these essential ecological allies stop acting as a carbon sink as extreme climate conditions become the norm.

Preserving tropical forests is thus essential. Their ability to continue acting as carbon sinks hinges on efforts to protect them and a collective commitment to limit global temperature rise. The Amazon's future depends on this, and so does ours.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

Rainforest quiz: Can you sort Earth's largest rainforests from biggest to smallest?

For decades, cities have been designed around "gray infrastructure." Roads move people. Bridges connect communities. Water systems protect public health. These systems are governed by engineering standards because society recognizes that safety cannot depend on good intentions alone.

Urban nature deserves the same recognition.

In June, a heat wave gripped Europe, breaking temperature records across the continent. In France, officials reported over 2,000 excess deaths. In the U.K., hospitals declared critical incidents and machinery and IT systems failed. In the U.S., a heat dome over the Midwest and East Coast disrupted Fourth of July celebrations, with at least 25 heat-related deaths over Independence Day weekend.

Cities are being tested by a warming climate. Yet one of our most effective forms of climate infrastructure is being lost — not because it does not work but because we still do not treat it as infrastructure.

My view is simple: Urban nature ‪—‬ including street trees, parks, wetlands and other urban green spaces ‪—‬ should be categorized and managed as essential infrastructure, with minimum standards for its protection, quality and long-term maintenance. Just as we regulate roads, bridges and drinking water, we need standards that ensure all urban residents benefit from healthy and thriving urban nature. Without such standards, cities will become hotter, less resilient and increasingly unequal as climate change accelerates.

Scientific research shows that urban trees and green spaces cool cities during heat waves, reduce flooding by absorbing stormwater, improve air quality, store carbon, support biodiversity, and improve both physical and mental health. During extreme heat, neighborhoods with mature tree canopies can be several degrees cooler than nearby streets dominated by concrete and asphalt. Those few degrees can mean the difference between manageable discomfort and dangerous heat exposure, particularly for older adults, children and people with existing health conditions.

But while the science is strong, our governance is not.

Cities enthusiastically announce ambitious tree-planting campaigns, biodiversity strategies and new greening targets. These initiatives are valuable, but they often focus on what is easy to count rather than what truly matters. Planting a tree is not the same as growing a healthy urban forest. Creating a park does not guarantee biodiversity. A green roof delivers little value if it fails during drought.

The real measure of success is whether urban nature continues providing benefits decades after trees are planted and established.

This is where cities are still falling short.

Unlike buildings or transport systems, urban nature rarely operates under consistent minimum standards. Many cities have no requirements for minimum tree canopy cover, adequate rooting space, soil quality, biodiversity targets, long-term maintenance or even whether newly planted trees survive. As a result, access to nature depends heavily on where people live. Wealthier neighborhoods often enjoy mature tree canopy and high-quality parks, while disadvantaged communities experience hotter streets, fewer green spaces and greater exposure to climate risks.

That is not simply an environmental issue. It is a public health issue, a climate adaptation issue, and an issue of social equity.

The solution is not simply to plant more trees. It is to establish urban nature standards that recognize nature as essential infrastructure.

These standards would not prescribe the same solution for every city. Instead, they would establish minimum expectations based on scientific evidence. They could include targets for accessible green space, minimum tree canopy cover, sufficient soil volume for healthy tree growth, biodiversity outcomes, long-term maintenance funding and routine monitoring to ensure that urban nature continues delivering benefits to communities.

Importantly, these standards should focus on outcomes rather than simple planting targets. Counting how many trees are planted tells us little about whether cities are becoming more resilient. Measuring survival, canopy development, ecosystem health and equitable access provides a much better picture of whether investments in urban nature are actually returning dividends.

Some critics argue that cities cannot afford stronger standards for urban nature. Municipal budgets are already stretched by housing, transport and aging infrastructure. But this argument overlooks a fundamental reality: We already spend enormous sums responding to the consequences of extreme heat, flooding, poor air quality and declining public health. Healthy urban ecosystems help reduce these costs while delivering multiple benefits simultaneously.

As climate change accelerates, the distinction between gray and green infrastructure becomes increasingly blurred. Trees cool buildings and reduce energy demand. Wetlands decrease flood damage. Parks improve public health and strengthen communities. These are not optional amenities. They are functioning components of urban infrastructure that deserve the same level of planning, investment and accountability as any engineered system.

Building codes transformed the safety of our cities because they established minimum standards that every development had to meet. Climate resilience now demands a similar transformation for urban nature.

The next generation of resilient cities will not be defined simply by how many trees they plant but by the standards they adopt to protect, restore and sustain the living infrastructure urban life depends on.

The real question is not whether cities can afford to invest in urban nature; it is whether they can afford not to.

Opinion on Live Science gives you insight on the most important issues in science that affect you and the world around you today, written by experts and leading scientists in their field.

June global sea surface temperatures have climbed to record highs, prompting concerns over extreme weather, flooding, sea level rise and stress to global ocean ecosystems.

The record, announced by the European Union's Copernicus Earth observation program on July 1, surpassed the previous record set in June 2024, with experts warning that more temperature records will likely be set over the coming months.

"Current conditions could indicate the beginning of a new phase, leading, once more, to uncharted territory," Carlo Buontempo, director of the Copernicus Climate Change Service at the European Centre for Medium-Range Weather Forecasts (ECMWF), said in a statement. "With ocean temperatures at these levels and El Niño on the horizon, we are likely to see more temperature records fall in the coming months.”

The record temperature was set on June 21, when the Copernicus Climate Change Service recorded global ocean surface temperatures of 20.86 degrees Celsius (69.55 degrees Fahrenheit), beating the record temperature of 20.83 C (69.49 F) set in 2023 and 2024. This measurement was corroborated by the Copernicus Marine Service, an independent dataset that reported temperatures of 21.0 C (69.8 F).

The recent sea surface heating did not occur evenly across the globe. In some areas, such as the Mediterranean, temperatures in June were up to 8 C (14.4 F) higher than average for the period from 1990 to 2020, as per data recorded on June 29, according to the European Space Agency.

The most significant rises in temperature were set in the Mediterranean, the Baltic Sea, bands across the Pacific and off the coasts of Northern Canada.

Warmer ocean temperatures have wide-ranging impacts. "Higher ocean temperatures keep the atmosphere warm for longer, provide extra energy to storms and increase evaporation, thus enhancing the potential for extreme precipitation and flooding," Copernicus Climate Change Service representatives said in the statement. "Ocean warming also contributes to sea level rise and ice melt, and stresses marine ecosystems."

According to data from the Copernicus Climate Change Service, the newly declared El Niño in the Pacific Ocean — the warm phase of a natural climate cycle. This El Niño is likely to reach levels that have not been seen in decades, with more temperature records expected to be set over the coming months as this Pacific heat is injected into an already warming world.

The service added that it remains to be seen whether these temperature spikes are temporary or indicative of longer term trends.

Plants, insects, and larger animals, like the forest’s white-faced capuchin monkeys, are well adapted to these changes. But in 2015, during an abnormally severe drought influenced by the El Niño–Southern Oscillation (ENSO), Perry, an evolutionary anthropologist at the University of California, Los Angeles, observed behaviors that once seemed impossible.

Under normal conditions "The [capuchin] mothers are quite devoted," she explained. "Now, I was seeing babies crying on the ground piteously. And the mothers just looking down like 'Too much trouble' and walking off, abandoning their infants."

"Even capuchins have their limits," Perry said. "And we need to start paying attention because all the weather predictions are saying that we're going to get more unpredictability and more climate extremes."

Monkeying around

Odd Jacobson, a behavioral ecologist at the Max Planck Institute of Animal Behavior, was a student at Lomas Barbudal in 2016, a year after this severe drought. His focus was on understanding how the study site's 12 different capuchin groups were moving through the forest. But now he's set out to investigate how else climate extremes may affect the behaviors and social structures of these monkeys.

In a paper published in Nature Ecology and Evolution, Jacobson and his coauthors — including Perry — analyzed how climate variability correlated to the 33 years of geolocation data they had on the capuchins.

Their first step was understanding how the size of each group was affecting the relationships between monkeys within the same group. To do this, they observed variables such as daily fruit intake, the size of the group's home range, and the distance the group traveled each day to find food.

Finally, to understand how monkey groups interacted, they used a "hierarchical social relations model," which allowed the scientists to predict how two different monkey groups would move through the forest and where their territories would overlap.

The team repeated this process, two monkey groups at a time, until they analyzed the interactions between all 12 monkey groups at Lomas Barbudal. Then, they added the climate-over-time layer to predict how the home range overlap and encounter rates (meaning moments where capuchins from two different groups engaged, often violently) would change with the seasons.

Strength (and weakness) in numbers

Generally, large monkey groups have advantages and disadvantages in the forest. One key advantage is the ability to control resource-rich areas, such as land with fruiting trees known as food patches. A key disadvantage is increased intragroup competition for food, meaning the daily fruit intake of individual monkeys was lower.

The researchers found that during climatic extremes, such as extremely wet or dry seasons, this intragroup competition intensifies, making the group less efficient at foraging overall. Behavior between groups changed with the climate as well. For example, in a typical dry season, large groups often overpower smaller ones to take over areas with more available fruit, such as along rivers.

But the new research found that this long-understood idea doesn't always hold true: During extreme climate events, like a dry season made even drier by the effects of El Niño, capuchins didn't try to hoard the higher-quality areas.

"We don't really know exactly why," Jacobson said. "Maybe there's not as much heterogeneity in the landscape during these resource poor times, and so there's not much that larger groups can monopolize."

Climate extremes, the research suggests, may be upsetting the balance that determines the optimal size of monkey groups. And, as a warming atmosphere makes climate extremes like El Niño or La Niña more intense, it's growing increasingly important to understand how these changes will affect animal societies.

Filippo Aureli, an ethologist at the Universidad Veracruzana, in Mexico, was not involved with this study, but he has studied the effects of extreme weather events on spider monkeys in Mexico. He also registered the infant mortality rates of capuchin and spider monkeys in the Costa Rican dry tropical forest during that 2015 drought. Capuchin populations experienced high infant mortality during the extreme event, while spider monkey populations tended to stop reproducing.

"With climate change, [climate extremes] are going to be more frequent and intense," Aureli said. "And we don't know what's going to happen. For this period [so far], they've held on very well, the spider monkeys, but we don't know for how much longer."

Perry agreed, noting "the importance of having a baseline when you're trying to study rare events like El Niño droughts."

"We know what normal is," she explained. "If you just try to drop in right now in all the chaos that we're starting to feel around the planet, then you really can't study it."

This article was originally published on Eos.org. Read the original article.

Growing water scarcity could hamper the expansion of lithium mining in the U.S., deepening its reliance on foreign imports over the coming decades, a new study finds.

Lithium is used in electric-vehicle and energy-storage batteries due to its high energy density and low weight compared with other minerals, but mining it requires a huge amount of water. Currently, the U.S. has only one active lithium mine, in Nevada, and with demand for the metal projected to explode over the next few years, the government and private companies are planning to open at least 115 new mines across the country, according to the study.

However, most of the proposed mines that are in advanced stages of development overlap with water-stressed areas, specifically in the western U.S. In the new study, published May 28 in the journal Communications Earth & Environment, scientists found that if lithium mines start operating in these regions, they will compete for water not only with households, agriculture and industry, but also with one another and with other proposed mineral mines.

"Future water availability under climate change may constrain whether new lithium mines will have sufficient water to operate," study senior author Jennifer Dunn, a professor of chemical and biological engineering and the director of the Center for Engineering Sustainability and Resilience at Northwestern University in Illinois, told Live Science in an email.

The U.S. imports more than 50% of its lithium, mostly from Chile and Argentina. Policymakers and corporations want to reduce this dependence, but even with the existing Nevada mine and the 22 proposed mines that are the closest to coming online, the U.S. won't have enough lithium to meet domestic demand, Dunn said.

"Every mine produces a different amount of lithium — depending on its deposit type, lithium grade, and final product — so we are unable to determine how many mines exactly would be needed," she said. "Our analysis estimated that if all 22 advanced [stage] proposed mines and the sole operating mine continued operation into 2050, 0.14 [to] 0.25 million metric tons [0.15 to 0.28 million tons] of lithium content in products could be produced per year."

This range falls short of the 0.83 million to 1.9 million tons (0.75 million to 1.7 million metric tons) of lithium per year that other researchers previously estimated the U.S. would need to cover its own demand.

However, the water demand to produce more lithium would be astronomical. That's because lithium is typically extracted from brines and rocks known as pegmatites, which require large-scale evaporation and aggressive processing with fresh water, respectively.

To find out if the U.S. would have enough water to support additional lithium mines under intensifying climate change, the researchers calculated the future water use of the 23 lithium mines most likely to be active in 2050, using data from mining companies. Then, they layered this projected water use on top of projected water uses from other sectors, such as agriculture and manufacturing, under four modeled socioeconomic-climate scenarios between 2040 and 2060.

The researchers found that the available water supply will, in most cases, be insufficient to support new lithium mines. The starkest example was Southern California's Salton Sea, which contains roughly 4.5 million tons (4.1 million metric tons) of lithium. The Salton Sea is fed by the Colorado River and showed the least water available to support lithium mining and other water demands, owing to the river's dwindling flow.

Lithium deposits in the U.S. are clustered in Nevada, Arizona and California. These are also some of the most arid and water-stressed states. Although the study found an increase in rainfall under a high emissions, "business as usual" climate scenario, these regions likely won't have enough water to support other activities, let alone additional lithium mining, Dunn said.

There were four exceptions in the study, including lithium-rich sites in North Carolina and Arkansas, which may have enough water to support future mines. However, there are other concerns related to lithium mining.

"Many of the lithium deposits in the United States reside near federally-recognized Indigenous and Tribal reservations, and the mines could violate Indigenous rights," Dunn said. "Lithium mining could also disturb sensitive ecosystems and biodiversity. And, like many other mineral mines, pollution, soil erosion, and water contamination are concerns."

Together, the findings highlight a catch-22 in the quest to source lithium: Lithium is essential to support a green energy transition and curb climate change, but shrinking water availability due to global warming is making it harder to extract lithium.

The study did not explore potential improvements to water-use efficiency that could reduce the pressure on some water resources and increase the availability for activities such as lithium mining. Nor did the researchers include water exchanges known as interbasin transfers (IBTs) in their analysis, due to the lack of studies about these transfers under climate change.

"IBTs could help supply water to arid or water-stressed regions," Dunn said.

Still, there is likely an upper limit on how much water can be allocated to lithium mining in a warming world, according to the study. This means the U.S. will probably continue to partially rely on foreign supply chains for lithium and other critical minerals.

The Amazon is the largest rainforest in the world, spanning more than 2 million square miles (5.2 million square kilometers) — an area 12 times the size of California. It influences global water cycles, stores years of global carbon emissions, supports 47 million people, and is home to the greatest concentration of biodiversity on Earth.

But the Amazon rainforest is also disappearing, with 17% of it already cut down or destroyed and largely replaced with agriculture. Other grave threats, such as oil drilling and illegal mining, continue to whittle it down. The next century may have outsize importance, as the forest could reach a "tipping point."

So what will the Amazon rainforest look like in 100 years?

The answer depends on a number of compounding threats, Bernardo Flores, a researcher with the EqualSea Lab at the University of Santiago de Compostela in Spain, told Live Science.

Encroaching farmland and organized crime are a couple of the problems chipping away at the Amazon. But those work in tandem with what he considers the three main threats: climate change, which can lead to extreme weather events, "like wetter wet seasons and drier dry seasons," deforestation and fire.

As the Amazon loses more of its forest, it triggers a feedback loop. "You have less rainfall; then you have less forest, [then] less rainfall, less forest," Flores explained. "That ultimately leads to "a global scale feedback involving the Amazon: More forest loss [leads to] more global warming. More global warming, more forest loss."

As forests get drier, it becomes easier for wildfires to burn more areas. Roads also degrade the forest, and "wherever you have roads, you have people doing illegal activities, illegal logging … then this leads to [more] forest fires," Flores said.

The "arc of deforestation" — a roughly 310,000-square-mile (800,000 square km) border along the Amazon considered the largest deforestation frontier in the world — offers a preview of what much of the Amazon could ultimately look like, according to Flores. The forests that remain there have higher tree mortality and more canopy gaps, and they are often "covered with lianas," or woody vines, that become an ecological problem, he said. Lianas compete with trees for light and nutrients in the soil, and significantly reduce not only a tree's chance of survival but also the overall diversity of trees in a forest. "When the whole forest is covered in lianas, you don't see the forest anymore," he added.

Invasive grasses introduced by cattle farmers will likely proliferate in the decades ahead, but "only a few parts" of the Amazon could become "a savanna, because a savanna is a native, biodiverse ecosystem," he said. Invasive grasses "exclude native species, reduce biodiversity" and would not allow native savanna grasses to replace the forest, Flores said. Instead, one possibility is a "degraded open-canopy ecosystem," where native, naturally fire-tolerant trees, combined with invasive grasses, vines and ferns, proliferate, Flores told Live Science.

Wildlife would quickly be affected as well. Aquatic species are especially vulnerable, Flores said. "When you start having these droughts that will simply last for one, two, three years," wetlands will dry out and become flammable, he explained. That could lead to "very quick extinctions in those areas."

The destruction of the Amazon rainforest would be disastrous for the Indigenous people living there, Christian Poirier, program director of Amazon Watch, an environmental and Indigenous rights advocacy group, told Live Science. "Imagine having your backyard bulldozed and your water source poisoned," he said. "You probably need to move from where you live, and that's exactly what's happening in the Amazon."

A devastated Amazon would also lead to "a more chaotic global climate system," Flores said. There could be less rainfall across parts of South America, and global warming will worsen. Earth could eventually reach a tipping point where ice sheets melt, ocean currents malfunction and the collapse of the Amazon accelerate warming all at once, pushing the planet to "cross the tipping point and transition to a much warmer climate," he said, leading to potentially irreversible consequences.

Unlike other major climate risks, such as the potential of the Greenland Ice Sheet melting and contributing to sea level rise, deforestation can in theory be reversed more easily by reforestation, said Arie Staal, an assistant professor of ecosystem resilience at Utrecht University in the Netherlands.

"That gives us a knob to turn that we don't have for other possible tipping points on Earth," he told Live Science. "It is clear that we really need to stop deforestation in the Amazon. And there's hope."

Editor's note: This article was updated at 6:23 p.m. EDT on June 22 to fix the conversion of roughly 310,000 square miles to 800,000 square kilometers.

Rainforest quiz: Can you sort the largest rainforests on Earth?

A single climate-change-fueled cyclone killed 7% of Tapanuli orangutans ‪—‬ the world's rarest great apes ‪—‬ in just four days last year, new research reveals.

The study shows that "climate change-driven weather poses an immediate, catastrophic threat to the world's rarest great ape," the researchers wrote.

Tapanuli orangutans (Pongo tapanuliensis) live in the Batang Toru forest in northern Sumatra, Indonesia. Pushed to the brink of extinction by habitat destruction, the entire species consisted of 767 individuals in 2019, of which 581 lived in the forest's west block.

Then, Cyclone Senyar arrived.

Across four days in November 2025, the rare and damaging tropical cyclone caused extreme rainfall and catastrophic landslides across this west block forest region, killing approximately 58 Tapanuli orangutans. These individuals died from drowning, suffocation under landslides, or impacts from collapsing trees, according to the study, which was published June 10 in the journal Current Biology.

The loss equates to 11% of the west block orangutans and roughly 7% of the whole species.

"It is extremely worrying for the future of this ape," study co-author Serge Wich, a professor of primate biology at Liverpool John Moores University in the U.K., told The Guardian.

World's rarest great apes

Tapanuli orangutans were classified as a new species, distinct from their Bornean (P. pygmaeus) and Sumatran (P. abelii) orangutan cousins, in 2017, making them the most recently identified, and rarest, species of great ape.

Orangutans are especially vulnerable to environmental shocks because of their slow rate of reproduction; they have roughly six- to nine-year gaps between each baby. They are also heavily dependent on tree cover to survive.

In the new analysis, researchers combined pre- and post-cyclone satellite imagery with orangutan population density estimates to evaluate the impact of the flooding and landslides on the apes.

Before the cyclone, 99.3% of the Batang Toru forest west block was forested. Then, after the storm's arrival, 21.8 inches (556 millimeters) of rain fell over four days, leading to landslides across 20,517 acres (8,303 hectares) of Tapanuli orangutan habitat. The researchers identified over 50,000 "scars" from this landslide-induced habitat destruction in the forest landscape.

This habitat loss was catastrophic for the orangutans. "Given the high density (>50,000) of sudden, steppe-slope landslides causing canopy collapse and debris flow into drainage networks, and the limited opportunity for arboreal [via trees] escape during rapid slope failure, we consider mortalities by burial, trauma, or subsequent drowning to be likely," the authors wrote in the study.

The long-term effects of topsoil destruction on the food supply will also harm the remaining orangutans, the authors wrote. With topsoil containing dense networks of plant-feeding fungi, it will take time for the fruit and leaves the orangutans rely on to return.

World Weather Attribution, a research group that studies extreme weather events, found that Cyclone Senyar was intensified by a combination of human-induced climate change, an ocean oscillation called the negative Indian Ocean Dipole, and La Niña, the cooler phase of the El Niño-Southern Oscillation climate cycle.

Climate change is projected to increase the frequency and intensity of heavy rainfall worldwide, including in Indonesia. And now that El Niño is officially here, the climate event will likely make the Pacific hurricane season stronger. This El Niño period is forecast to "rank among the largest El Niño events in the historical record going back to 1950," NOAA officials wrote in a June 11 update.

"El Niño conditions will pour fuel on the fire of a warming world," U.N. Secretary-General António Guterres said in a June 2 video statement. "The world must treat it as the urgent climate warning it is."

It's official: El Niño is here, and it's shaping up to be among the strongest ever recorded.

The natural climate cycle, which supercharges temperatures and shifts weather patterns across the planet, officially took hold over the past month, according to a June 11 update by the National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center.

What's more, an accompanying average of various forecasting models gives a "63% chance of a very strong El Niño during November-January that would rank among the largest El Niño events in the historical record going back to 1950," NOAA officials wrote in the update.

This is no longer much of a surprise. Last week, the European Centre for Medium-Range Weather Forecasts, considered the "gold standard" of global weather models, suggested that this year's brewing El Niño would likely become the strongest ever recorded.

That prediction is increasingly shared by the world's best climate models, with about 75% of them now forecasting a record-breaking surge of at least 4.5 degrees Fahrenheit (2.5 degrees Celsius) above average sea surface temperatures across key parts of the Pacific Ocean, according to Europe's Copernicus Climate Change Service, with other model scenarios climbing as high as 7.2 F (4 C).

For reference, the past two strongest recorded El Niño events (2015-2016 and 1997-1998) sent ocean temperatures to 4.1 F (2.3 C) above average in the Niño 3.4 index, which measures sea surface temperatures across a key region of the Pacific Ocean.

What is El Niño?

El Niño events occur every two to seven years as part of the El Niño-Southern Oscillation (ENSO) natural climate cycle in the Pacific Ocean. The ENSO cycle flips between the warmer El Niño phase and the cooler La Niña phase, with neutral periods in between. El Niño periods bring elevated sea surface temperatures in the central and eastern Pacific, thereby weakening or reversing trade winds and strongly disrupting global temperatures and rainfall patterns.

Earth's last El Niño ran from June 2023 to April 2024, delivering an injection of heat to our already-warming world that made 2024 the hottest year on record. That year was also the first to breach the 1.5 C (2.7 F) warming limit — a key guardrail set by the Paris Agreement, beyond which the effects of climate change are predicted to become increasingly disastrous.

The current El Niño will also raise global temperatures this year and next, making it likely that Earth will reach, or even surpass, those previous records.

Now that El Niño's onset is official, scientists can advise people around the world on how to prepare. The impacts of this extra burst of heat stand to be profound, with studies linking previous El Niño periods to famine in Europe; civil wars in tropical regions; and droughts, floods and forest fires around the world. This year's El Niño will arrive during a period of already-increased global food insecurity driven by the Iran war.

And while El Niño would have occurred regardless, scientists are seeing signs that this El Niño's quicker-than-expected onset was driven by humanity's warming of the planet.

"It might be one of the most rapid transitions that I've seen in the record ‪—‬ maybe the most rapid," Nathaniel Johnson, a research meteorologist and member of the ENSO seasonal forecast team at NOAA, told Live Science in a May 1 interview. "Because, to go from a weak-to-moderate La Niña to a strong-to-very-strong El Niño within one calendar year is just not something we see very often."

"Over the past century, we have seen an increase in these more rapid swings from one state to the other," he added. "So there's some suggestion that potentially climate change could play a role in making these swings more rapid between El Niño and La Niña. It's something that will take more investigation."

On a blazing hot day in South Africa, female southern pied babblers can't think straight. The medium-sized black-and-white birds are trying to get at tasty mealworms behind a see-through barrier. On cooler days, the birds can quickly figure out that all they have to do is go around the small wall of plastic. But when the mercury goes up, the birds just keep stubbornly pecking at the barrier.

That experiment is part of a growing body of research showing that animals get their minds muddled during heat waves. When it's hot outside, birds struggle to learn, dogs bite more often, goat-like chamois pick fights. This is bad news not just for those who get on Fido's toasted nerves. If the animals can't stay alert enough to find food or avoid predators, their chances of survival go downhill, says Amanda Ridley, a behavioral ecologist at the University of Western Australia who coauthored the pied babbler study.

With climate change making heat waves more common, such cognitive impairments across the animal kingdom could ripple through entire ecosystems, putting already fragile species at greater risk. If pollinators forget which flowers to visit, crops and wild plants may fail. If birds can't find food as easily, their young may not survive. And on a warming planet, a sharp mind is particularly vital. "A changing climate means that your ability to behaviorally adapt is even more important," Ridley says.

Hotheaded

There is plenty of evidence that animals are affected by heat. Birds, for example, spend less time looking for food and feeding their young; they even sing less. Instead, they'll sit around for hours with wings spread to dissipate the heat, and pant with their beaks wide open. Some animals retreat to shade or hide in cool burrows — again, skipping meals. Bees, meanwhile, splash their faces with droplets of water midflight when the weather is sizzling. This way, "they get convective cooling for their brain," says Emily Baird, a neuroscientist at Stockholm University.

Some of the first hints that hot temperatures can mess up minds, however, came from studies on humans. Back in the 1800s, Belgian astronomer Adolphe Quetelet noticed that violent crime in France peaked in the summer. Later studies linked high temperatures with gun violence, mental-health-related hospital admissions, suicide and gambling. When it's hot, people have trouble making decisions, and their memory suffers. For students at schools without air conditioning, a school year just one degree Fahrenheit hotter reduces test scores by 1 percent, a study found.

Increasingly there's evidence that other species may also be more aggressive when mercury shoots up. A 2023 study that combed through nearly 70,000 reports of dogs biting people across eight US cities, from Chicago to Baltimore, found that such incidents were more likely to happen on hot, sunny and smoggy days. The risk was 10 percent higher on a 90-degree day than on a 60-degree day — and not only because people are more apt to venture out for walks when the sun is shining (the researchers controlled for seasonal effects in their data).

Still, the scientists were unable to determine whether dogs get more aggressive as it gets hot, or if cranky humans provoke more attacks. "It's likely that both humans and dogs get stressed and more irate at higher temperatures," said Clas Linnman, a neuroscientist at the University of Miami and a coauthor on the study.

And it's not only dogs: A 2025 study out of China showed that many animals, including snakes and cats, are more inclined to bite people when it gets hot.

Animals also seem to lose their cool with each other, especially if there is food involved. Scientists used binoculars and spotting scopes to spy on wild goat-like chamois that feed on protein-rich plants on the slopes of the Italian Apennine Mountains. More than 1,600 hours of observations over two summers revealed that when temperatures rose from 54 to 64 degrees Fahrenheit, vegetation grew scarcer, and chamois aggression in turn shot up. The animals became territorial over patches of food, they assumed threatening postures, chased each other — attacks that, at times, escalated. The study authors predict that chamois aggression will go up 50 percent by 2080 due to climate change.

The small tropical fish called a golden julie also gets confrontational in the heat. Ordinarily, when a golden julie is placed in front of a mirror, it sees its reflected image as a stranger and shows some hostility, raising its fin, for example. But if the normally 78-degree water is raised to a hot 84 degrees, the fish is more likely to get aggressive, and may bite and slap its tail against the mirror, as it tries to scare or attack the reflected image.

Cognitive problems

Heat waves can also hamper the ability of animals to learn, as Ridley and her colleagues observed with the southern pied babblers. In one of their experiments, the birds were presented with a simple wooden block with two holes drilled in it, each covered with a lid. If the bird pecked at the lid, it would rotate, revealing either an empty hole or a tasty mealworm (the babblers, Ridley says, "are highly motivated by mealworms"). One lid was dark, and the other a lighter shade of the same color. During heat waves, the birds needed twice as many trials to learn that the mealworm was always hidden under the lid of the same shade.

Another group of scientists tested zebra finches, pretty Australian songbirds, and discovered that if temperatures are high, they too have cognitive problems. When figuring out how to get a mealworm out of a see-through tube with an opening at one end, they would just keep pecking on the tube, says study coauthor Elizabeth Derryberry, an evolutionary biologist at the University of Tennessee, Knoxville. It's the bird equivalent of "banging your head against a brick wall," she says.

Adding to the tally, several years ago researchers showed that when the heat is on, mice have trouble finding their way around a maze and forget objects they've seen the day before. More recently, researchers found that male guppies, popular aquarium fish, also have trouble getting through a maze after spending several days in heat-wave-like 90-degree water, even if the prize for getting it right is a virgin female — which they tend to find particularly attractive.

For animals such as fish and insects that can't control their body temperature, heat waves could be particularly detrimental. "Changes in air temperature will affect brain temperature," says Baird. A hotter brain could hinder the functioning of nerves, and that, she says, "might affect sensing, memory and learning."

When Baird and colleagues tried to teach bumblebees to associate sweet sucrose with the color blue and bitter quinine with yellow, most of the bumblebees learned the trick at 77 degrees, but fewer than half managed to do so at 90 degrees. Such impaired cognition could spell trouble in the field: If the insects forget which flowers they should pollinate (in the case of bumblebees, these include tomatoes and blueberries) or how to get back home with nectar, not only will the pollinators suffer, but human agriculture too, Baird says.

Heat appears to dangerously diminish animal vigilance as well. In Ridley's recent experiments, once mercury in the Kalahari Desert reached 96 degrees Fahrenheit, pied babblers lost their ability to properly respond to predators. In their studies, researchers lured birds toward a mystery shape covered in a sandy-colored blanket, using worms as bait. Once a babbler approached, the scientists would reveal what was hidden underneath: either a taxidermied cat-like carnivore called a genet, or a similarly sized and colored wooden box. The birds got scared of the genet in cooler temperatures — they'd call out, scan their surroundings, or simply flee. But once it got hot, they behaved similarly whether they were facing the carnivore or the box. Ridley suggests that this could translate into higher chances of fatal predator attacks as heat rises, which could harm populations of babblers and other prey species.

These studies are not just abstractions. In the Kalahari, where southern pied babblers use their wits to search for worms, temperatures are rising twice as fast as the global average. In tropical rivers, where male guppies seek mates, heat waves are growing longer and more intense. It's the same story across much of the planet — temperatures climb, and animal thinking becomes strained, potentially putting species at risk. The effects may be magnified in certain areas such as cities, which often exhibit even warmer temperatures than non-urban areas. If anything, Ridley says, "We are probably underestimating the impacts of increased heat on animal minds."

This article originally appeared in Knowable Magazine, a nonprofit publication dedicated to making scientific knowledge accessible to all. Sign up for Knowable Magazine's newsletter.

This year's brewing El Niño will likely become the strongest ever recorded, a new forecast warns.

New predictions by the European Centre for Medium-Range Weather Forecasts (ECMWF) suggest sea surface temperatures in a key region of the central equatorial Pacific Ocean will climb 5.4 degrees Fahrenheit (3 degrees Celsius) above average by December of this year, with some scenarios showing they could go above 7.2 F (4 C).

If the forecast bears out, it means that this year's El Niño — the warm phase of a multi-year natural climate pattern that supercharges temperatures across the globe — will be significantly stronger than the previous joint record holders of 2015 to 2016 and 1997 to 1998.

Those past two El Niño events sent temperatures in the Niño 3.4 index (which measures sea surface temperature anomalies between 5 degrees north and 5 degrees south latitude, and 120 degrees west and 170 degrees west longitude) to 4.1 F (2.3 C) above average.

"Almost every scenario now reaches past +3˚C, with a cluster of high-end scenarios in excess of +4˚C," Ben Noll, a meteorologist and global weather writer at the Washington Post, wrote on the social platform X. "This outlook now depicts the strongest El Niño on record."

El Niño events occur every two to seven years as part of the El Niño-Southern Oscillation (ENSO) natural climate cycle in the Pacific Ocean. The ENSO cycle flips between the warmer El Niño phase and the cooler La Niña phase, with neutral periods in between. El Niño periods bring elevated sea surface temperatures in the central and eastern Pacific, thereby weakening or reversing trade winds and strongly disrupting global temperatures and rainfall patterns.

Earth's last El Niño ran from June 2023 to April 2024, delivering an injection of heat to our already warming world that made 2024 the hottest year on record and the first to breach the 1.5 C (2.7 F) warming limit — a key guardrail set by the Paris Agreement, after which the effects of climate change become increasingly disastrous.

The impacts of previous El Niño periods on global agriculture have been profound, with studies linking the events to famine in Europe; triggers for civil wars in tropical regions; and droughts, floods and forest fires around the world. This year's El Niño will arrive during a period of increased global food insecurity driven by the Iran war.

In an update on Tuesday (June 2), the World Meteorological Organization (WMO) warned that the climate pattern has an 80% chance of forming before September and a 90% chance before November, and that the world should prepare for a potentially strong event.

"The science is clear: El Niño is arriving on our doorstep in the coming months with 90% certainty. The world must treat it as the urgent climate warning it is," UN Secretary-General António Guterres said in a video statement.

And while El Niño would have arrived regardless of anthropogenic climate change, Guterres was careful to stress that it will add more heat to an already dangerously warming planet.

"El Niño conditions will pour fuel on the fire of a warming world. Impacts will hit even harder, travel even farther, and cross borders with devastating speed," he added.

"The only effective response is climate action equal to the crisis — ending the addiction to fossil fuels, accelerating the shift to renewables, protecting the most vulnerable, and delivering early warning systems for all."

Mangrove forests, long considered among the world's most threatened ecosystems, are now showing signs of global rebound, a new study reports. These findings mean experts are cautiously optimistic about gains in coastal protection.

The results are based on 40 years' worth of satellite data, which shows that mangrove forests are more resilient than expected. Gains over the past 16 years have outpaced losses, leaving the world with about a 1% net decline in mangrove area since the 1980s, far less than previous estimates suggested. The findings were published Thursday (June 4) in the journal Science.

Historically, mangrove populations have been declining mainly because coastal development, aquaculture and agriculture have cleared large areas of mangrove forests. Pollution and rising sea levels have also weakened these ecosystems, shifting the balance of saltwater and freshwater that these trees need to survive.

"After decades of loss, we're finally seeing a global turning point for mangroves," study first author Zhen Zhang, a postdoctoral scholar in the School of Science and Engineering at Tulane University in Louisiana who specializes in mangrove forest coverage, said in a statement. "This highlights their strong resilience and their potential as a powerful nature-based solution for climate mitigation and coastal protection."

Eyes in the skies

Mangroves make up salt-tolerant forests full of shrubs and trees that grow along tropical and subtropical coastlines. They protect coastal communities by acting as a natural barrier against storms, strong winds and flooding. Their dense root system helps slow down storm surge and reduces erosion by holding shoreline soil in place. Mangrove forests also help support ecosystems because their tangled roots provide safe habitats where fish, crabs, shrimp and other marine animals can grow before moving into open waters.

These forests are also important in the fight against climate change, as they store large amounts of carbon in their trees, roots and deep muddy soils, helping to reduce the amount of carbon dioxide in the atmosphere.

To track the changes in mangrove populations, researchers at Tulane's Mangrove Lab used long-term observations from the Landsat program, a joint mission between NASA and the United States Geological Survey (USGS). The researchers combined Landsat's digital eyes with high-resolution satellite imagery from the European Space Agency's PlanetScope to validate the mangrove maps.

"Ground fieldwork is extremely valuable, but it is often costly, and doesn't allow this large-scale perspective," Daniel Friess, a professor of Earth and environmental sciences at Tulane and the director of the Mangrove Lab, told Live Science in an email. "Satellite observations allow us to fill these gaps and detect long-term changes in places where field measurements are sparse or unavailable."

The team used machine-learning techniques to create baseline mangrove maps for the 1980s, 2010 and 2021, then applied change-detection methods to generate annual records from 1984 to 2023. Those maps allowed the researchers to calculate yearly mangrove losses and gains across the globe and identify a shift from a global decline before 2010 to a net gain after 2010.

The rebound was driven by both restoration and natural expansion, according to the researchers. In some places, mangroves have recolonized abandoned aquaculture ponds. In others, the forests have spread onto newly formed coastal mudflats, particularly in river deltas where sediment creates favorable conditions.

Along the U.S. Gulf Coast, warming temperatures have also encouraged mangroves to expand into higher-latitude areas. Louisiana has seen an overall increase in mangrove area over the past 40 years, while mangroves in the Mississippi River Delta began increasing more sharply after 2012, the researchers said.

But the findings, while encouraging, do not mean mangroves are safe. Friess said continuing losses must be halted so that mangrove forests can continue to rebound.

"We may have underestimated the state of the world's mangroves, " Friess said, as there is evidence that the forests are naturally regenerating and expanding. "It means that if we can halt continuing loss through conservation, then we may see an even bigger gain in the world's mangroves."

Recovery remains fragile

A separate study published Wednesday (June 3) in the journal Earth's Future warned that rising seas could reduce the amount of carbon dioxide mangrove forests store and, in some cases, turn them from carbon sinks, storing more carbon than they emit, into carbon sources, in which they would emit more carbon than they could store.

The researchers used a model that combined water flow, sediment movement, carbon storage, and mangrove growth and dieback — when a large number of mangrove trees rapidly die off — to get a bigger picture of mangrove ecosystems. They found that sea level rise may increase carbon storage in some localized areas at first, but whole-forest carbon storage is likely to decline over the next century, meaning more carbon will be kept in the atmosphere, adding to the effects of climate change. Mangroves need a certain amount of tidal flooding to survive, but too much flooding could cause them to disappear.

The findings underscore the ongoing need to protect existing mangroves so they can continue protecting ecosystems and sequestering carbon. Friess said he hopes global gains continue, but the effects of climate change could lead to losses instead.

"While we hope that net gains in mangrove area will continue, it may be challenging to maintain this trajectory in many places under climate change," he said. "So we need to focus on conserving and restoring mangroves now in order to give them the best chance in the future."

A single day of attacks on four Iranian oil refineries produced as much sulfur dioxide (SO₂) as a volcanic eruption, a new analysis finds.

Remote sensing from Chinese and European meteorological satellites has revealed that fires caused by Israeli airstrikes launched on Iranian refineries and storage facilities on March 7 emitted a total of around 33,000 tons (29,800 metric tons) of SO₂ by March 8. The toxic gas cloud had traveled roughly 1,240 miles (2,000 kilometers) by March 9, reaching as far as East Asia, according to a study published Tuesday (May 26) in the journal Advances in Atmospheric Sciences.

Although the cloud had largely dissipated by the end of March 9, the impact of the "major emission event" should not be neglected because of its relatively short duration, the authors wrote in the study.

The pollutants mixed with precipitation to produce potentially corrosive "black rain" loaded with toxic particles such as hydrocarbons, and "some residents [in Tehran] experienced headaches, a bitter taste in the mouth, eye and skin irritation, and breathing difficulties," the authors wrote in the study.

The ongoing war between the U.S., Israel and Iran is already known to be releasing an extraordinary amount of carbon dioxide (CO₂) alongside other greenhouse gases. A recent analysis found that, between Feb. 28 and March 14, the war contributed more CO₂ than Iceland emitted across the whole of 2024.

Now, researchers have mapped the size and trajectory of the SO₂ plume emitted following the March 7 attacks on the Fardis, Shahran, and Aghdasieh oil depots, and the Tehran Oil Refinery. To track the cloud, the scientists analyzed ultraviolet and infrared hyperspectral imaging data — which combines information about particular locations alongside spectral data — obtained by China's FengYun 3 satellites and the European Space Agency's Sentinel-5 Precursor satellite.

The scientists found that the amount of SO₂ in the atmosphere in Tehran rose sharply on March 8. The affected area spanned roughly 185,000 square miles (300,000 km²) with northeasterly winds sending the giant plume as far as East Asia.

By comparison, Iceland's 2010 Eyjafjallajökull volcano eruption spewed roughly 22,000 tons (20,000 metric tons) of SO₂ in total over a three day period. The ash plume was so vast that it grounded flights in Europe for almost a month after a series of eruptions, and caused various health repercussions, with exposed individuals experiencing breathing difficulties in the following months.

SO₂ is a major precursor of acid rain, which has profound environmental impacts, such as removing nutrients from soil and polluting waterways. Pollution, including from sulfur dioxide, is also linked to depression, anxiety and other mental health problems. Research is needed to determine the specific public health impacts of the attacks on the Iranian oil refineries.

A vital ice shelf is about to break away from Antarctica's "Doomsday Glacier," further destabilizing one of the world's largest and most vulnerable glaciers.

The Thwaites Glacier is nicknamed the "Doomsday Glacier" because its collapse would send so much ice into the Southern Ocean that global sea levels would rise by 2.1 feet (65 centimeters or 26 inches), flooding coastal communities worldwide. This collapse could take centuries, but there is an imminent threat to Thwaites' eastern ice shelf, which will likely accelerate the glacier's demise.

Researchers say that satellite images reveal that the Thwaites eastern ice shelf is about to detach from the glacier, New Scientist reported last week. While the glacier sits on land, the ice shelf is a floating body of ice that is attached to the glacier's mouth. Researchers still have a lot to learn about the glacier, but this shelf acts as a buttress, restraining the flow of ice from the glacier into the sea.

Robert Larter, a marine geophysicist at the British Antarctic Survey, said that the ice shelf is very likely to break up in 2026. Larter runs the U.K. arm of the science coordination office at the International Thwaites Glacier Collaboration, where U.S and U.K. research agencies have investigated the glacier's complex and rapidly changing environment

"The last bit of ice shelf in front of the glacier is poised to disintegrate," Larter told Live Science in an interview. "We don't know quite how this ice shelf is going to break up, but it's definitely going to go."

Around the size of Florida, Thwaites Glacier is the largest glacier in West Antarctica. The gigantic river of ice is more than 6,500 feet (2,000 meters) thick in some parts and 75 miles (120 kilometers) across — making it Earth's widest glacier.

The glacier has been melting rapidly since the 1980s, losing hundreds of billions of tons of ice. That's due to relatively warm ocean water flowing underneath the ice shelf and melting the glacier at its base, where ice sits on ground that's below sea level. The glacier has retreated around 12.4 miles (20 km) since 1992.

Modeling the demise of massive glaciers is a complex task, making it hard to put an exact date on when Thwaites Glacier will finally collapse. However, a study published March 9 in the journal Geophysical Research Letters found that the glacier could be losing 180 billion to 200 billion tons of ice per year by 2067.

Thwaites Glacier's slow collapse is part of a wider concern among scientists for the future of the West Antarctic ice sheet. Thwaites is a key pillar of the ice sheet, protecting other ice from slipping into the ocean. If the whole ice sheet were to go, sea levels would rise by 10.8 feet (3.3 m), according to the British Antarctic Survey. The collapse of ice sheets like this one are considered tipping points, or "points of no return," in the fight against climate change — meaning that once they are crossed, they bring about permanent changes that cannot be reversed for many thousands of years.

The Thwaites eastern ice shelf is fracturing where the shelf is held in place by a ridge on the ocean floor, and at the mouth of the glacier. Larter said that movement on the western side of the shelf, where the ice is breaking away, has approximately doubled over the last eight months.

Much like other Antarctic sea ice — and the glacier itself — this shelf is undermined by warmer, saltier water being forced up from deep below the surface of the Southern Ocean. Larter noted that it's more about the circulation of water than warming, but indications are that human-driven climate change is ultimately to blame.

"There is an active scientific debate about exactly how this works, but it seems pretty clear that in some way, the changes to the Southern Hemisphere westerly winds are what is driving warm water onto the continent," Larter said. "And those wind changes are part of the wider pattern of climate change that we're seeing."

Archaeologists investigating a 17th-century graveyard in the High Arctic are uncovering evidence of the perils that plagued early modern whalers, including extensive physical labor in their jobs and diseases such as scurvy. But the burial site is disappearing rapidly due to climate change, making archaeological excavations a race against time.

Likneset, which means "Corpse Point" in Norwegian, is the largest whaling burial site on Svalbard, an archipelago halfway between the North Pole and the northern coast of Norway. Hundreds of shallow graves marked with stone cairns have been found there in a cemetery that dates to the 17th-to-18th-century boom in Arctic whaling.

In a study published Wednesday (May 20) in the journal PLOS One, archaeologists examined 20 burials from Likneset and found that the men buried there lived short, difficult lives — and that these burials are at risk of disintegrating due to climate change.

"Early modern Arctic whaling was among Europe's first large-scale extractive industries, and the labor was highly manual," study first author Lise Loktu, an archaeologist at the Norwegian Institute for Cultural Heritage Research, told Live Science in an email. Loktu co-wrote the study with Elin Therese Brødholt, a forensic anthropologist at Oslo University Hospital.

The work carried out by the whalers was extremely physically demanding, involving tasks like rowing boats, hauling live whales, towing carcasses, processing blubber, and performing heavy shipboard work under cold, wet and physically exhausting conditions.

"What is striking in the skeletal material is that we can actually see this workload reflected in the body," Loktu said.

In their analysis of the whalers' skeletons, Loktu and Brødholt found evidence of degenerative joint disease, trauma, and extensive strain in the men's shoulders, upper chest, spine, hips, knees and feet.

"Several very young adults already show advanced wear and degeneration normally associated with much later stages of life," Loktu said, suggesting these men were overusing their bodies for a long period of time.

The vast majority of the whalers also had evidence of scurvy, a deficiency of vitamin C that leads to muscle weakness, bleeding gums, tooth loss, anemia and a host of other problems. Scurvy is rare in modern countries where fresh fruit and vegetables are available, but it frequently affected sailors on long-distance journeys in the 15th to mid-19th centuries. At that time, Europeans did not understand the biological cause of scurvy and tended to avoid eating foods that Indigenous Arctic people consumed to prevent it, such as muktuk, a dish of whale skin and blubber that is a good source of vitamins C and D.

"Scurvy does not only affect bones; it also compromises the immune system, increases vulnerability to infection, weakens wound healing and contributes to overall physical decline," Loktu said. "We believe this likely played an important role in weakening the men physically."

The researchers also found dental evidence that most of the men smoked a pipe. By constantly clenching a clay pipe between their teeth, the men developed circular indentations in their enamel. Smoking is known to deplete the body's stores of vitamin C, which could have contributed to the development of scurvy.

"While smoking itself cannot explain the scurvy, tobacco use may potentially have worsened overall health and nutritional stress," Loktu said. "It seems likely that prolonged hard labor, nutritional stress, disease and general physical frailty ultimately became the 'last straw' that tipped already weakened bodies beyond recovery."

Loktu and Brødholt also focused their study on Likneset because parts of the burial site have already been lost to coastal erosion. They compared graves excavated at three times — the late 1980s, 2016 and 2019 — and discovered that the permafrost-preserved burial area found 40 years ago was already collapsing due to climate-driven processes, including rapid Arctic warming. This may present problems for future studies of early modern whalers.

"Rapid Arctic warming is accelerating the degradation of permafrost-preserved archaeological sites, placing organic-rich whaling burials on Svalbard among the most vulnerable heritage contexts," the researchers wrote in the study. These findings suggest that preservation conditions should continue to be monitored, "as climate-driven degradation and coastal erosion are rapidly reducing the informational value of archaeological archives on Svalbard," they wrote.

What do you know about the bones in your body? Test your knowledge with our human skeleton quiz!

Climate change is pushing rice-growing regions into temperatures beyond those at which rice has been cultivated in the past 9,000 years of human history, new research finds.

Research suggests that warming is proceeding 5,000 times faster than rice has ever evolved.

This means rice may be reaching its "thermal limit," the point at which it can't easily adapt to rising temperatures. Although people can breed more heat-resistant strains or move rice cultivation into new regions, future warming is likely to cause serious disruption for the billion people who depend on rice cultivation for their livelihoods, said study first author Nicolas Gauthier, an anthropologist and geographer at the Florida Museum of Natural History.

"We don't want to downweight the flexibility of human adaptation," he told Live Science. "But we also want to acknowledge that these adaptations have already occurred, and in some cases, we might be closer to the limits of what we can reasonably adapt to in that time frame."

Rice is a staple crop for over half of the world's population, and 90% of cultivation occurs in Asia. Some rice-growing regions are already being hit by severe warming, which is affecting rice yields, according to the World Economic Forum.

Although rice is a heat-loving crop, rice photosynthesis shuts down at around 104 degrees Fahrenheit (40 degrees Celsius), and too much heat can also affect pollen viability and grain growth. Rice is also a water-intensive crop, so shifts in the wet and dry seasons are a problem, as is sea-level rise because low-lying paddies may become inundated with salt water, which can kill the crop.

Gauthier and his colleagues gathered data on past climate from archaeological sites where scientists have found evidence of rice cultivation over nearly a millennium. They found that rice has often expanded into cooler regions as humans have bred cold-tolerant plants and adjusted their agricultural practices. But, he added, the upper temperature limit has stayed the same since the beginning of rice cultivation about 9,000 years ago.

In the history of rice farming, cultivation has remained limited to places where the mean annual temperature is below 82.4 F (28 C) and the maximum temperature in the warm season stays below 91.4 F (33 C), on average, the researchers reported in the journal Communications Earth & Environment.

Climate change might warm regions where it is currently too cool to grow rice, enabling a geographical shift in cultivation, Gauthier said, but there will be challenges. Rice paddies have been built up over centuries, and it's not easy to "just pick up and move," he said. And the disruption in rice cultivation will have major economic and food security impacts, he said.

"You could keep global rice production the same" by moving cultivation around, he said. "But that's not fixing the problem for people who live in South Asia who are relying on rice for their consumption."

Editor's Note: The headline of this story was changed at 10:45 a.m. EDT on May 23 to better reflect the current study's findings.

A "super" El Niño is now the most likely scenario from October 2026 to February 2027, according to a new forecast from the National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center.

El Niño is the warmer phase of the natural El Niño-Southern Oscillation (ENSO) climate cycle, a periodic shift in the waters of the tropical Pacific Ocean that supercharges global temperatures, in turn impacting weather patterns and crops worldwide.

Now, in a new ENSO forecast published May 14, NOAA estimates that there's a 65% chance that the upcoming El Niño will be classified as strong or very strong starting in October, potentially placing it among the strongest in recorded history.

A "very strong" El Niño — meaning a 3.6-degree-Fahrenheit (2 degrees Celsius) rise in sea surface temperatures, and unofficially called a "super" El Niño — is now the most probable scenario for the October-to-February period.

There is also now an 82% chance that El Niño will arrive between now and July, with the phase looking highly likely to continue until February 2027. This is a roughly 20 percentage-point increase in certainty from NOAA's April forecast that El Niño is right around the corner.

A "very strong" El Niño could wreak havoc

El Niño events occur every two to seven years, when shifts in wind and current patterns in the tropical Pacific Ocean cause sea surface temperatures to rise 0.9 F (0.5 C) above historical averages, resulting in profound knock-on effects on the global climate. The world is rapidly exiting the neutral phase.

The world's most recent El Niño spanned from May 2023 to March 2024 and was partially responsible for 2024 being the hottest year on record. If the upcoming El Niño is strong or very strong, 2027 could surpass the previous record, according to Climate Brief's State of the Climate assessment, published April 21.

In fact, the impending El Niño may itself break records. "Confidence is clearly shifting higher on potentially the biggest El Niño event since the 1870s," Paul Roundy, a professor of atmospheric and environmental sciences at the University at Albany, wrote on X on May 5.

If a "super" El Niño does occur, it could rival the strongest on record: a catastrophic 1877 event that spurred the 1876-to-1878 global famine. The famine killed over 50 million people, or 3% of the world's population at the time.

Although the social, political and economic landscapes have changed since the 1877-to-1878 El Niño, the upcoming event could still seriously threaten food, water and economic security around the world, Deepti Singh, head of the Climate Extremes and Impacts Lab at Washington State University, told The Washington Post.

"What is different now is that our atmosphere and oceans are substantially warmer than they were in the 1870s, which means the associated extremes could be more extreme," Singh said.

More recent examples demonstrate the threat of strong and very strong El Niño phases. For example, an El Niño in 1997 to 1998 led to an estimated global economic loss of $32 billion to $96 billion.

NOAA ENSO forecaster Nathaniel Johnson recently told Live Science that a very strong El Niño would impact fisheries and crops, as well as heighten the risk of wildfires and hurricanes in parts of the world.

"You've got more people that are living in poverty already and if you get a reduction in crop yields because of drought or flooding [from El Niño] then that drives prices even higher," Liz Stephens, a professor of climate risk and resilience at the University of Reading in the U.K., told the BBC. "So we're looking at potentially quite huge humanitarian impacts this year, especially if the crisis in the Middle East continues."

The next NOAA ENSO forecast will arrive June 11.

Antarctica's sea ice started shrinking dramatically in 2015 after resisting global warming for decades, and researchers now know why.

A study published May 8 in the journal Science Advances reveals that Antarctic sea ice succumbed to strong winds that disturbed the Southern Ocean's layers, replacing cold and relatively fresh surface water with warmer, saltier water that caused some initial melting. As sea ice declined over the years and reflected less sunlight back to space, the ocean absorbed more heat, thus accelerating the loss way beyond what scientists were expecting.

The research identified three phases of Antarctic sea ice decline between 2013 and 2023. Previous data shows that sea ice extent hit a record low in February 2023 and that Antarctica was missing a chunk of ice bigger than Western Europe at winter's peak in July of the same year. The continent has not recovered since, with sea ice extent reaching another near record low in 2024 and remaining below the 1981-to-2010 average in 2025 and early 2026.

"The system is behaving in a different manner," study first author Aditya Narayanan, a physical oceanographer at the University of New South Wales in Australia and the University of Southampton in the U.K., told Live Science. "Obviously, something has changed."

To pinpoint what caused such sudden and rapid sea ice loss, Narayanan and his colleagues used a model and observations from satellites and sensors in the Southern Ocean. The researchers fed the real-life data into the model to constrain its output and bring the results closer to what scientists have watched unfold in Antarctica since 2015.

"The model we used is sort of a hybrid," Narayanan said. "It digests all of the observational products that we feed into it, and it also runs a numerical model, much like a climate model."

Phase 1: Westerly winds push surface waters north

As in real life, sea ice in the model expanded between 2013 and 2015. The Southern Ocean's surface was cold and relatively fresh during this period, but the simulation showed that a warm, salty layer deep beneath the surface was rising and eroding the winter water layer — a thick band of frigid water that, up until recently, served as a barrier to protect surface waters from warmer waters below.

Study co-author Theo Spira, a researcher in the Alfred Wegener Institute at the Helmholtz Center for Polar and Marine Research in Germany, reported in a March paper that the winter water layer has been thinning since 2005. That's because the Southern Hemisphere westerlies, which are strong winds that blow eastward around Antarctica, picked up due to the ozone hole above the continent, Narayanan said. The ozone hole strengthened the Antarctic polar vortex, which, in turn, intensified the westerlies.

Strong westerly winds around Antarctica displace surface waters northward, causing the water below to rise to replace them. This process unfolds very slowly, and the immediate response of the Southern Ocean to stronger winds in the 2000s and early 2010s was to grow more sea ice, because cold fresh water reached farther out along the margins of the frozen continent, Narayanan said.

"The hypothesis already existed in the literature that when you strengthen the winds, you get a response from the ocean on two different timescales," he said. "The immediate response is to see a growth in the sea ice coverage. But then, if you keep this going for a few years or up to a few decades, you start to get this slower response. It takes a while, but what happens is, the heat that's deeper in the ocean starts to rise up, simply because you're moving waters away."

Phase 2: Warm water rises and initiates melting

In 2015, the westerlies became even stronger, accelerating the movement of surface waters away from Antarctica and the rise of warmer, saltier layers to replace them. By this point, the ozone hole was recovering, but the atmosphere was warming due to human greenhouse gas emissions, which have the same effect of intensifying the westerlies, Narayanan said.

The model showed that warm, salty water penetrated the winter water layer and reached the surface, where the water underwent turbulent mixing due to the powerful winds. "After 2015, you clearly see enhanced mixing from below of heat and salt," Narayanan said. "Our study bears it out that the initiator of sea ice loss was this heat from below."

The salt weakened the layers that naturally occur in the Southern Ocean, meaning more heat and salt could migrate upward after the initial breach in 2015. This feedback mechanism sped up sea ice melt, particularly in East Antarctica, the study found.

Phase 3: Heat and salt trigger feedback loops

By 2018, so much sea ice had melted in Antarctica that the decline became a self-reinforcing process.

Sea ice loss reduced the amount of sunlight that was reflected into space by this white surface and increased the amount of heat absorbed by the Southern Ocean, especially in the summer. This delayed the growth of sea ice every subsequent fall, as the ocean had to transfer its excess heat to the atmosphere before it could produce sea ice. The later in the year that sea ice forms, the smaller sea ice extent becomes and the more heat the ocean absorbs, Narayanan said.

Sea ice is a source of fresh water when it melts in the summer, and previously, this helped to keep the Southern Ocean's surface cold and relatively fresh. But the less sea ice grows in fall and winter, the less fresh water is available to maintain the Southern Ocean's natural layers. "A saltier upper ocean means you can keep the vertical layering weak and you keep the vertical mixing going," Narayanan said.

This is what led to the record-low sea ice extent observed in 2023. And if humans keep pumping greenhouse gases into the atmosphere, there is little hope that Antarctica will recover, because our emissions are strengthening the westerlies and warming the atmosphere, Narayanan said.

"If we keep emissions going, we will see sea ice receding farther and farther out to the continent, but I'm not sure how quick that change is going to be," he said.

An uncertain future

Climate change is expected to boost precipitation over the Southern Ocean, which could counteract the westerlies' impact on sea ice. More melting of Antarctic glaciers and ice sheets could also restore the ocean's layers. Therefore, it remains unclear if Antarctica has reached a tipping point, Narayanan said.

"Is it a collapse? Not yet," he said; but currently, the frozen continent is completely out of whack and behaving like a "new system."

Antarctic sea ice exhibits considerable year-to-year change, so it may be an oversimplification to think about this system in terms of a tipping point, said Ariaan Purich, a senior lecturer and climatologist at Monash University in Australia who was not involved in the research.

"For Antarctic sea ice, rather than thinking of tipping, we can think of abrupt change," Purich told Live Science in an email. "There is building evidence that Antarctic sea ice has undergone an abrupt change to a new low coverage state. A big question remains over whether sea ice will stay relatively stable in this state, or continue to decline over the coming years."

The Southern Ocean has absorbed roughly 75% of the excess heat in the atmosphere over the past 50 years, and sea ice plays a major role in this storage. When sea ice forms, it releases salt that creates dense, northward-flowing currents, which carry heat and carbon from the atmosphere to the depths of the ocean.

As sea ice shrinks, salt becomes less concentrated in the Southern Ocean, thus preventing the water from sinking and storing heat and carbon at depth. "That's something that's concerning, if it [sea ice loss] changes the balance, and if it reduces the ability of the Southern Ocean to store heat and carbon at depth," Narayanan said.

Plenty of organisms also rely on sea ice to survive, including krill, dolphins, whales and penguins. Sea ice loss has already impacted the ecosystem in Antarctica through mass die-offs in penguin colonies.

The sudden switch from high sea ice extent in the 2000s and early 2010s to record-low extent in the mid 2020s "is one of the largest present-day climatic shifts in the Earth system," Narayanan and his colleagues wrote in the study. A cascade of undesirable events could come from this, including less carbon and heat storage, more global warming, ecosystem degradation, and exposure of Antarctic ice shelves to warmer water as sea ice disappears.

Editor's Note: This article was updated at 5:20 a.m. ET on May 19 to include comments from Ariaan Purich, who was not involved in the new study.

Antarctica quiz: Test your knowledge on Earth's frozen continent

MAHARASHTRA, INDIA — In clinics and labs around the world, scientists are uncovering a consequence of air pollution that received little attention for decades: Polluted air not only damages the lungs and heart but also harms the brain.

Large studies conducted in Asia, the United States and Europe have linked long-term exposure to air pollution with a higher risk of depression, anxiety and cognitive decline, while lab- and animal-based studies hint at possible mechanisms driving this effect. Research suggests pollution may also increase the risk of schizophrenia and bipolar disorder, and even suicide risk.

The scale of the problem is staggering, as air pollution affects almost everyone on the planet.

Roughly 99% of the global population breathes air with pollution levels exceeding the World Health Organization's air-quality guidelines, with the most polluted air often found in low- and middle-income countries. In India, where pollution levels are among the highest in the world, these findings may help to explain mental health symptoms that many people have silently experienced for years, scientists told Live Science.

Pollution's mental toll

Areas of India with long-term exposure to high pollution have provided some of the strongest evidence of this link.

A 2025 analysis surveyed 359 people in northern India, finding that residents of communities living within 3 miles (5 kilometers) of coal-fired thermal power plants were more likely to report stress, anxiety and depression than those living farther from these power plants. Women, in particular, were affected.

Notably, people's overall exposure to air pollution sources is also shaped by gender roles. Household air pollution is common in rural homes in India because biomass fuels, such as firewood, dried cow dung cakes, and crop residues, are used for cooking or heating water. In an analysis of nearly 30,000 adults ages 60 and above across India, those using these solid fuels were more likely to report depressive symptoms than those using cleaner cooking methods like electricity or liquefied gas, even after accounting for factors such as economic status, education, health, and living conditions. Women often spend several hours near traditional cooking stoves or other smoke sources each day, thereby intensifying their exposure over that of men who aren't tasked with cooking. A similar pattern has been observed in other Asia-Pacific countries.

That's borne out by the experience of Rukmini Manjare, 54, who lives in Bubnal village in the Indian state of Maharashtra. For many years, she worked outside in the sugarcane fields, where the burning of husks produces a smoky haze.

But unlike the men in her family, she also spends hours cooking over a traditional stove. A decade ago, she started feeling restless and anxious whenever pollution levels spiked.

Recently, Manjare's family tried to reduce her smoke exposure by installing a solar water heater. But smoke from nearby homes still drifts into her house.

"Almost every family uses the traditional stove for at least two hours in the morning daily," she told Live Science.

Worldwide problem

Manjare's experience is a common one across the Indian subcontinent, where nearly the entire population of 1.4 billion people breathes air that exceeds safe pollution limits. In 2023, for instance, the country's average fine particulate pollution, called PM2.5, was about 41 micrograms per cubic meter ‪—‬ more than eight times the level the World Health Organization has deemed safe.

Evidence from other population studies points in a similar direction. In a February analysis of almost 35,000 adults from 12 Indian states, scientists examined the effects of long-term exposure to PM2.5. These tiny particles measure 2.5 micrometers or smaller, meaning they can penetrate deep into the lungs. Living in areas with higher fine-particulate pollution levels, on average, was associated with greater odds of having been diagnosed with depression or anxiety.

This analysis looked at both the average pollution levels in different areas and the composition of that pollution, examining how specific components of PM2.5 were associated with mental health outcomes. Some components of the air pollution — such as carbon-rich molecules and secondary inorganic aerosols, like sulfates, ammonium and nitrates — showed stronger associations with depression and anxiety than others did. Those components better predicted mental health outcomes than total pollutant concentrations alone did.

Treating air pollution as a single, uniform pollutant may therefore "underestimate its mental-health impacts, particularly in countries such as India, where pollution sources and chemical composition vary widely by region and season," said study senior author Sagnik Dey, head of the Centre for Atmospheric Sciences at the Indian Institute of Technology Delhi.

The mental health effects build up over long periods, making them easy to overlook at the individual level. But when millions of people are exposed over decades, "these small effects can add up to a substantial mental health burden at the population level," Dey told Live Science.

India's data on pollution reflects a global pattern. In a December 2025 analysis of health records from 23.7 million older adults in the United States, long-term exposure to PM2.5 was associated with a higher risk of late-life depression. This link persisted even after accounting for factors such as income and education, which can also influence mental health. Similar patterns have been observed in Europe.

When pollution becomes personal

While population-level data identifies broad trends, they may conceal how disabling the symptoms can be for individual people.

Manjare told Live Science that her symptoms of anxiety have worsened over the past decade. Now even minor worries trigger physical symptoms. "Whenever I feel stressed and anxious, my blood pressure shoots up," she said. "I cannot handle even a minute of stress anymore."

The episodes are often accompanied by severe pain in her legs and neck. At times, the only relief comes from a pain-relief injection at the local clinic. "I have now gotten used to it," she said.

Over time, Manjare began noticing a pattern. On days when the air looks hazy and gray and a smell of smoke lingers, her breathing feels a little heavier than usual. On those days, she feels unusually dull and anxious. "There's this sense of constant worry, which I find it difficult to explain," she said.

Part of that anxiety comes from anticipating an episode of pain. But she also says the anxiety emerges on the hazy days before any physical symptoms start.

These changes have taken a toll. She rarely feels like eating. "I love cooking food for everyone, but most of the time, I don't feel like eating it myself," Manjare said. The persistent stress eventually forced her to stop working in the sugarcane fields.

Manjare's worsening symptoms coincide with rising levels of air pollution in the region. Several traditional brick-making kilns operate nearby, and with sugarcane planting nurseries proliferating, farmers frequently burn farm residue, adding another layer of pollution. Vehicles and nearby industries add to this mix, as does smoke from household stoves, where firewood and plastic seedling trays are burned daily to heat water for bathing.

The pollution is visible in everyday life. "If you leave white clothes outside to dry, they turn dark within an hour." On some days, soot settles so quickly inside the house that she sweeps the floor every hour.

After years of living in these conditions, Manjare can often sense when pollution levels have risen, even without checking air-quality readings. "I immediately experience elevated blood pressure, a constant feeling of helplessness, and I stop stepping out of the house," she said.

Around 12 miles (20 kilometers) away, in Jambhali, Maharashtra, more than 100 sugar cane nurseries fill the air with smoke and fine particles — and residents Lalita Koli, 63, and Krishnabai Koli, 65, report similar symptoms.

Koli spent six years working in the sugarcane fields, but she quit because the anxiety, physical symptoms and sense of dread became too much for her.

On heavily polluted days, Koli feels dizzy and develops full-body pain.

After years of living in these conditions, Manjare can often sense when pollution levels have risen, even without checking air-quality readings. "I immediately experience elevated blood pressure, a constant feeling of helplessness, and I stop stepping out of the house," she said.

Around 12 miles (20 kilometers) away, in Jambhali, Maharashtra, more than 100 sugar cane nurseries fill the air with smoke and fine particles — and residents Lalita Koli, 63, and Krishnabai Koli, 65, report similar symptoms.

Koli spent six years working in the sugarcane fields, but she quit because the anxiety, physical symptoms and sense of dread became too much for her.

On heavily polluted days, Koli feels dizzy and develops full-body pain.

"Sometimes I feel like I will die any moment," she said. "I sit and cry, but it's very difficult to explain what is happening to me."

Pollution and the brain at the cellular level

Several biological pathways may help to explain what Manjare and others like her are experiencing. Payel Kundu, a doctoral researcher at the Indian Institute of Technology Delhi, who co-authored the study with Dey, noted that one of the key mechanisms is likely neuroinflammation, a process in which the brain's immune system becomes activated.

PM2.5 is small enough to enter the bloodstream and reach the brain by crossing the blood-brain barrier. The particles can travel directly from the nose to the brain along the olfactory nerve, and they may also indirectly affect the brain via the gut-brain axis, the communication network linking the digestive system and the brain, Kundu told Live Science.

Laboratory studies suggest that when brain cells are directly exposed to fine particulate pollution, they incur damage that impairs their function and triggers cell death. Cell and animal-based studies find that brain tissue responds to pollution by activating its immune defenses, while also producing unstable molecules that damage cells ‪—‬ an effect known as oxidative stress.

While many cell-based studies of inflammation and pollution focus on neurodegenerative diseases or developmental disorders, studies also link neuroinflammation with anxiety and depression.

Certain components of fine particulate pollution, such as carbon-rich particles and secondary inorganic aerosols, seem key to activating the immune and inflammatory pathways in the brain, Kundu said.

PM2.5 may also disrupt the signaling of brain chemicals involved in mood, such as dopamine and norepinephrine. In addition, fine particulate pollution can also interfere with a key component of the body's stress-response system, known as the hypothalamic-pituitary-adrenal axis.

Animal experiments are beginning to show a causal link between polluted air, neuroinflammation and mental health problems. In one study, mice exposed to higher levels of fine particulate pollution — around 185 micrograms per cubic meter showed more depression-like behavior than mice exposed to only 58 micrograms per cubic meter. The high-pollution group moved and explored their surroundings less, and in a water-based stress test, they spent more time floating without trying to escape. In another study, mice exposed to real-world fine particulate pollution for four, six and eight weeks developed depression-like behaviors, alongside changes in inflammatory signaling and in certain signaling pathways involved in neuron growth and function.

Air pollution can also affect mental health indirectly. Wei Jie Seow, an assistant professor at the Saw Swee Hock School of Public Health at the National University of Singapore, said polluted air is already known to contribute to heart and lung diseases. Those physical health problems are closely linked with higher rates of depression and other mental health challenges.

"So part of the mental-health effect may actually be mediated through declining physical health," Seow told Live Science. In a study of more than 17,000 adults ages 45 and older in China, her team found that ozone was tied to the largest increase in depressive symptoms among the pollutants examined.

Ozone, a reactive gas formed when sunlight interacts with pollutants from vehicles and industrial manufacturing, has been linked to inflammation and an increased risk of cardiovascular disease. Cardiovascular conditions, in turn, are associated with a higher risk of depression, suggesting one way such pollution affects mental health.

Despite the growing evidence, scientists say many questions remain. Yang Liu, a professor of environmental health at Emory University in Atlanta whose research has linked air pollution to the risk of depression, said the next step is to better understand how PM2.5 affects depression risk by conducting long-term studies that track people over time while also measuring pollution exposure and signs of brain inflammation.

Another gap lies in understanding how these risks unfold across different populations and environments. Future research needs to focus on long-term studies that follow people over time, especially in low- and middle-income countries, Dey suggested.

It may also need to look beyond pollution. Air pollution rarely occurs in isolation; it often coincides with other environmental pressures, such as extreme heat, noise and social stress, Dey noted. Understanding how these overlapping stressors interact is crucial for designing effective interventions and policies.

No easy solutions

While scientists are still uncovering exactly how polluted air affects the brain, many say the most obvious solution is to clean the air.

"If we reduce pollution at the source, we reduce exposure for everyone simultaneously, including vulnerable populations who may not have the means to protect themselves individually," Seow said.

Population-level policies that curb emissions from transportation, industry and power generation are therefore critical, researchers say. Liu noted that studies have linked improvements air quality with better mental health outcomes, so as air quality improves, so does mental health.

Some scientists say solutions should focus not just on reducing overall pollution levels but also zero in on especially harmful particulates. "Not all PM2.5 particles are equally harmful, so targeted interventions may be more effective than strategies that focus only on reducing overall PM2.5 levels," Dey said.

Reducing emissions of sulfur dioxide, nitrogen oxides and ammonia could limit the formation of secondary particles such as sulfates, nitrates and ammonium, which are more strongly associated with mental health outcomes, Dey said. Cutting emissions from traffic and reducing the burning of biomass for fuel could also reduce exposure to carbon-rich particles, he added.

At the same time, individual and community-level measures can help. Expanding green space and limiting heavy traffic near homes could improve both air quality and psychological well-being, Liu suggested.

Measures such as improving indoor air filtration and avoiding high-exposure environments on heavily polluted days, where possible, also may help, Seow said.

For Manjare, the problem is not just the polluted air, but how easily it goes unseen. “If we could show how pollution levels rise through the day, from daily activities as well as sources like industry, traffic, and crop burning, people would understand how serious it is,” she said.

Editor's Note: This story was supported by Earth Journalism Network as part of the Following the Fumes cross-border collaboration

Ocean temperatures reached a near-record-breaking monthly high in April as forecasters warn that we could be on the cusp of one of the strongest El Niño events of the century.

El Niño is the warm phase of a multi-year natural climate pattern that increases global temperatures. Forecasters have predicted that there's a one in four chance that an unusually strong, or "super" El Niño, could emerge this year, with new data suggesting that warming El Niño conditions will soon be upon us.

The European Union's Copernicus Climate Change Service has found that sea surface temperatures in April reflected a transition to El Niño conditions. Across the extrapolar global ocean, which encompasses all oceans except for the icy Arctic and Antarctic regions, surface temperatures were the second highest for any April on record (21 degrees Celsius, or 69.8 degrees Fahrenheit), trailing only those seen in April 2024 (21.04 C, or 69.87 F) — the warmest April ever recorded.

Earth's last El Niño ran from June 2023 to April 2024, delivering an injection of extra heat to our already warming world. Both years saw temperature records tumble, with 2024 ending up the hottest on record and the first to breach the 1.5 C (2.7 F) warming limit, a key guardrail set by the Paris Agreement before which the effects of climate change become increasingly disastrous. Notably, the 2023/2024 El Niño was on the cusp of the "super" threshold.

El Niño is marked by atmospheric and sea temperature changes in the tropical Pacific Ocean. Of course, Earth and its oceans are heating up anyway due to human-caused global warming, so the spike in sea surface temperatures last month is about more than natural climate patterns.

"April 2026 adds to the clear signal of sustained global warmth," Samantha Burgess, the strategic lead for climate at the Copernicus Climate Change Service, said in a statement. "Sea surface temperatures were near record levels with widespread marine heatwaves, Arctic sea ice remained well below average, and Europe saw sharp contrasts in temperature and rainfall; all hallmarks of a climate increasingly shaped by extremes."

The El Niño-Southern Oscillation cycle (ENSO) triggers a warm El Niño and then a cold La Niña around every two to seven years. Each phase tends to last around nine to 12 months, but the timing of their emergence and duration varies.

The National Oceanic and Atmospheric Administration (NOAA) recognizes El Niño conditions when the eastern tropical Pacific Ocean is 0.5 C (0.9 F) or more warmer than the historical average, while wind, surface pressure and rainfall in the region are also consistent with El Niño conditions.

Last month, NOAA's Climate Prediction Center announced that there is a 61% chance of El Niño emerging between May and July, which would then very likely persist through the rest of 2026. The center also gave a one in four (25%) chance of a very strong El Niño (above 2 C, or 3.6 F) emerging during the upcoming Northern Hemisphere winter, which is when El Niño conditions typically peak.

NOAA is unusually confident in its El Niño forecast for this time of year, which tends to be less accurate in spring due to the season's chaotic weather. However, the tropical Pacific Ocean appears to be rapidly moving away from La Niña conditions (0.5 C below the historic average), which occurred between September and January, through neutral conditions, and towards a potentially strong El Niño.

"If this does turn out to be a very strong El Niño, it might be one of the most rapid transitions that I've seen in the record ‪—‬ maybe the most rapid," Nathaniel Johnson, a research meteorologist and member of the ENSO seasonal forecast team at the Climate Prediction Center, told Live Science in an interview published May 1.

The cause of this year's potentially supercharged El Niño will be explored after the fact. However, Johnson noted that there's some suggestion that climate change could potentially be playing a role in making El Niño and La Niña swings more rapid, though this has yet to be confirmed.

"Super El Niño"

Many meteorological organizations don't recognize the term "super El Niño," but it's an informal way of saying "very strong El Niño." Potential impacts of such an event include a decline in fisheries, as well as droughts, wildfires and coral bleaching.

The Climate Prediction Center is one of several groups predicting El Niño and the potential for supercharged conditions. The U.K.'s Met Office is another, and has said that confidence is growing in projections that this upcoming event could be at the upper end of the historical range.

"A 'super' El Niño is not a term we subscribe to, but it does underpin the fact that this is likely to be a significant event," Grahame Madge, a senior press officer and climate science communicator at the U.K. Met Office, said in a statement released April 15. "Scientists are telling us that this could be the strongest El Niño event this so far century, comparable to the notable El Niño event in 1998."

The 1998 event, which began in 1997 and lasted for 13 of the NOAA's overlapping three-month sea surface temperature averaging periods (between May 1997 and June 1998), saw temperatures rise up to 2.4 C (4.3 F) above the historical average, according to NOAA data. The only very strong El Niño to occur this century was of a similar magnitude. Between 2015 and 2016, El Niño conditions lasted for 20 overlapping three-month periods, and peaked at 2.8 C (5.04 F) above the historical average, according to NOAA. However, the 2015/2016 event was weaker than the 1997/1998 event in the eastern Pacific.

El Niño typically increases global temperatures by about a fifth of a degree Celsius, according to Madge. This is a temporary rise on top of global warming, which, regardless of its influence on the ENSO cycle, is the reason our planet is warming.

Will 2026 be the warmest year on record?

Carbon Brief has predicted that 2026 is likely to be the second-warmest year on record, while a strong El Niño developing later this year increases the likelihood that 2027 will be the warmest year ever recorded.

World leaders previously agreed to limit warming to preferably below 1.5 C and well below 3.6 F (2 C) in the 2015 Paris Agreement, a legally binding international treaty. The Paris Agreement is for temperature anomalies averaged over at least 20 years, so while 2024 was warmer than 1.5 C, the limit hasn't technically been breached yet, though the United Nations Environment Programme expects warming to speed past the 1.5 C climate threshold in the next decade.

Microplastics are absorbing heat in the atmosphere and contributing to global warming, a new study reveals.

Microplastics are infamous for being everywhere, contaminating ecosystems and accumulating inside our bodies. Scientists have known for a while that plastics are also blown high into the atmosphere, where they are now pervasive, but it was unclear what impact they might be having up there.

Now, the new study, published Monday (May 4) in the journal Nature Climate Change, has found that overall, plastic particles create a warming effect. This is because, while very-light-colored plastics scatter sunlight back into space, darker-colored plastics absorb sunlight and radiation.

Study co-author Drew Shindell, a distinguished professor of Earth science at Duke University, told Live Science that the climate change impact of plastic particles is fairly small ‪—‬ comparable to the emissions of a small country. In numbers, this is the equivalent of around a couple of percent of the contribution from carbon dioxide (CO₂) — the main driver of climate change — or a couple hundredths of a degree of warming. However, the researchers' modeling was based on a limited understanding of the amount of plastic in the atmosphere, so the extent of the warming effect is uncertain.

"The key finding is really that the warming strongly outweighs the cooling," Shindell said. "I think we have a lot of confidence in that because we did all of these measurements in the laboratory of how [microplastics and nanoplastics] interact with sunlight. What we don't have so much confidence in and what's still a big uncertainty is exactly how many of these are in the atmosphere."

Microplastics come from larger plastic debris that breaks up and from plastic products that are designed to be microscopic in the first place, such as the tiny beads used in some facial scrubs and shower gels. A plastic is classified as a microplastic when it has a width of 1 micrometer to 5 millimeters (0.00004 to 0.2 inches). Anything less than 1 micrometer is classified as a nanoplastic.

To better understand how different colors of microplastic and nanoplastic particles behave, Shindell's colleagues in Shanghai collected plastic debris and studied its reaction to sunlight and radiation. They also checked whether very light colors would darken in the atmosphere over time ‪—‬ and found that they did.

"Sometimes if you get a parking pass or something that you put on your windshield, the plastic yellows with time because it's out in the sunlight," Shindell said. "We thought maybe particles of plastic do that, too."

Once the team understood how the plastic particles behaved, Shindell and his colleagues in the U.S. used that data alongside data on plastic emissions to model their impact. This modeling was hampered by uncertainty surrounding the quantity and distribution of plastics in the atmosphere.

"People have mostly taken measurements near the ground because they were thinking of these as a health hazard, which they are, but the climate is influenced by not just the amount at the surface but throughout the atmospheric column," Shindell said.

The analysis revealed that the warming effect from the microplastics and nanoplastics is about five times larger than their scattered cooling effect, establishing them as a previously unrecognized driver of global warming. And while the impact of microplastics on warming is tiny compared with the effect of burning fossil fuels, getting rid of plastic waste is another thing humanity could do to slow climate change, Shindell noted.

"It just adds another compelling reason why we should pay more attention to keeping plastic waste out of the environment," he said.

As the planet warms due to climate change, extreme heat is threatening global food security by harming crops and livestock and reducing the number of hours farmers can work.

A recent report by the U.N. Food and Agriculture Organization and the World Meteorological Organization warned that the impacts of extreme heat are pushing agricultural systems to the brink. The agencies found that half a trillion working hours are lost due to extreme heat each year — and the impacts will only worsen as global temperatures continue to climb.

The U.N.'s warning came the day after the Lancet Countdown ‪—‬ an international research collaboration that monitors key indicators of health and climate change ‪—‬ published its own report on health and climate change in Europe. Among its findings, the report highlighted that climate change is already causing heat-related deaths, unsafe working hours and food insecurity.

Live Science spoke with Shouro Dasgupta, an environmental economist and a co-author of the Lancet Countdown report, about extreme heat and agriculture in the wake of the new reports. Here's what he had to say.

Patrick Pester: How does extreme heat impact food production?

Shouro Dasgupta: Our crops are productive when the temperature is within a certain range. With extreme heat, we often see this range being breached. The other part is that, with high heat, crops wither, so many of them don't even get close to being harvested. Those are the two most common extreme heat impacts. Drought is another one. In many parts of the world, we now see prolonged droughts or droughts unprecedented in the history of that region.

PP: What does the U.N. report reveal that we didn't know already?

SD: This report is more for synthesis. It brings together the body of knowledge that currently exists, and it also focuses on several aspects of crop production. There are numerous case studies from all over the world — from the impact of heat on certain types of crops, all the way to livestock. It has a very detailed chapter on livestock, which is often not as well researched as crops.

PP: So animals aren't as productive when it's hot?

SD: Exactly, and it's dangerous for their health. For millions of farmers, their livelihoods and income depend solely on livestock, and as extreme heat generally kills livestock around the world, it's not just the supply of food that is being affected, but at a very human level, the livelihoods of these farmers are being destroyed.

PP: And it's going to be harder for farmers to work if it's very hot.

SD: It reduces their productivity because they have to take frequent breaks to protect their health, which brings us to the fact that agricultural workers also tend to have the least amount of social protection. They don't usually have contracts, and for millions of agricultural workers, unless they're working, they're not earning anything. So they often have to sacrifice their health in order to keep working.

PP: You published your Lancet report the same week as the U.N. report was released. What's different about your report, and what have you found?

SD: The Lancet Countdown is focused on indicators. Two of the indicators are very relevant to the discussion we're having. The first one is the impact on food insecurity in Europe, which is access to food. Our results show that compared to the 1981 to 2010 baseline, a higher frequency of heat waves and droughts has resulted in 1 million additional people becoming food insecure in 2023 alone. So the message is, food insecurity is no longer just about low-income countries. This is happening now in Europe.

The second indicator that I want to mention is the impact of warming on high-exposure sector workers. This is where we focus on working hours in agriculture and construction sectors in Europe. Our result shows that, due to warming between 2020 and 2023, on average, warming has resulted in a reduction of 24 hours per worker per year ‪—‬ so workers are having to reduce their working hours to protect their health. When they reduce their working hours, they earn less, which affects their livelihoods. And when they earn less, the profits of the company or the farm they work for also declines. This is transmitted to lower output and, eventually, lower economic growth.

PP: Is everyone going to be impacted by this if it's a global issue?

SD: At some point, yes. There is a lag between shocks on the workforce and the price we pay in the supermarket. But eventually, these impacts will be transmitted through the supply chain. At the same time, food production itself is being affected by extreme heat, and the joint effect of this results in increasing prices.

PP: How do we address this? Can we address this?

SD: Yes. I think it's important that we give a positive message.

There are policies that can be implemented to protect the agriculture sector and agricultural workers — safety nets. By safety nets, I mean proactive safety nets. We need to anticipate food insecurity events before they become famine. And safety nets — whether in the form of cash benefits, cash transfer or food assistance — have to be anticipated. We can no longer rely on reacting after an event has taken place.

Other policies, especially in the agricultural sector, would be investing in climate-resilient crops and salinity-resilient crops. In these cases, there can actually be learning from Global South to North. Countries such as Bangladesh, where I'm from, have more than three decades of experience in developing climate-resilient and salinity-resilient crops.

Editor's note: This interview has been condensed and edited for clarity.

Research suggests we are on the brink of crossing several ecological "tipping points" that could derail ecosystems like the Amazon rainforest and permafrost-covered tundras. But just as humans can cause these negative tipping points, we can also trigger positive ones that restore ecosystems, says Tim Lenton, a professor of climate change and Earth system science at the University of Exeter in the U.K.

In a new perspective article, Lenton argues that positive tipping points are key to hitting targets enshrined in various biodiversity and ecological restoration frameworks, including the United Nations Decade on Ecosystem Restoration 2021-2030. Examples of these targets include restoring 30% of all degraded ecosystems and conserving 30% of land and water by 2030.

Lenton's article was published Monday (April 27) in the journal Nature Sustainability. Live Science spoke with him about what constitutes a positive tipping point, the most encouraging examples we've seen, and the actions people can take to help restore ecosystems.

Sascha Pare: We often hear scientists talking about tipping points that unleash undesirable ecosystem changes that harm biodiversity. But what is a positive tipping point, as opposed to a negative one?

Tim Lenton: A tipping point, in general, is where a small change makes a big difference to a system, because you pass a threshold where some amplifying feedback, typically within that system, gets strong enough to support a self-propelling change from one state of the system to another. That sort of change tends to be self-accelerating, initially; it tends to be abrupt; it tends to be hard to reverse. And that applies whether the change is a good one or a bad one.

I've spent a lot of time working on what we might call negative tipping points in the climate and the biosphere. But a positive tipping point is one that we're going to normatively decide is good. I've written extensively about positive tipping points to get us to zero greenhouse gas emissions, but this particular paper is focusing on what tipping points are positive for nature. We're still net destroying nature at the moment, but various governments have signed up to the idea that we need to be regenerating nature. So, in this case, I try to define a positive tipping point for nature as something that ecologists would agree was a shift in the state of an ecosystem or even a big biome that was nature-positive.

If we take a canonical case like the dieback of coral reefs and their replacement with a macroalgal or seaweed goo, generally ecologists and people who fish in the surrounding area would all agree that it's a positive if you could tip back to the thriving, flourishing coral reef. With the Amazon case, if we've destroyed the Amazon for cattle ranching, then from a nature point of view, the positive tipping would be back to a healthy, fire-suppressing, rainfall-recycling forest.

SP: Can you give some examples of positive tipping points where we can see that the ecosystem has undergone positive change?

TL: A classic case is the reintroduction of wolves to Yellowstone National Park. When the last wolf was hunted to local extinction [around 1926], it then unleashed the population of elk and other grazers to go wild and eat down the saplings of many tree species. So then, you had a lot less wooded or forested [areas in] Yellowstone Park. But when the wolves were reintroduced [in 1995 to 1996], it triggered what's called a trophic cascade, where you saw record-breaking recovery, especially of the riparian vegetation — the vegetation around water courses and shallow bits of the landscape.

Another famous one is sea otters off the Pacific West Coast of North America. They were hunted to local extermination [in the 18th and 19th centuries]. What you saw when you lost the otters is that urchins that the otters loved to eat went crazy and ate down all the kelp and destroyed this wonderful kelp forest, which changed the whole ecosystem. As the population has begun to recover through less hunting and deliberate reintroductions in the Alaskan region, otters come back, eat urchins; kelp bounces back; and the whole ecosystem is reinstated.

I touch on a bunch of other ones [in the article], too. There was the eutrophication of the Norfolk Broads [in England] and other shallow lakes. [Eutrophication is an excessive enrichment of water with nutrients.] It was a long journey, but by controlling the nutrient inputs — the runoff — into those waterways, we eventually managed to, in some cases, tip recovery of clear waters and flourishing, more complex ecosystems. Those are all tipping points in nature.

I also talk about cases of positive tipping for nature, but the tipping might be in society. We see the positive tipping of the spread of, say, marine protected areas, or some [other] nature-conserving or regenerating activity.

And then I get into the territory of, could we positively tip the drivers of nature destruction? The simple one is that people eat too much meat, especially red meat. Is there the potential to positively tip change? There's trends in the right direction in the U.K. and several other rich nations, with people eating less red meat. And then there's India — a country where, for cultural reasons, there's way less meat consumption. That shows that an alternative stable state of diet is possible.

SP: In your recent book, "Positive Tipping Points: How to Fix the Climate Crisis" (Oxford University Press, 2025), you write about positive tipping points that could accelerate the energy transition away from fossil fuels. What are some of those tipping points?

TL: There are a lot of important amplifying feedbacks in society that have been enabling a spread of clean, zero-emission technologies, whether it's electric vehicles or the adoption of solar panels. These amplifying feedbacks include things like the fact that the more people who adopt the clean, green alternative, the more they can influence other people to adopt it.

We tend to learn from each other. But actually, the beauty of those technologies is that the more solar panels or electric vehicle batteries we make, the better and cheaper they tend to get. There's something we call the increasing returns: The more who adopt [something], the more attractive it becomes for the next person to adopt, because the thing is more affordable, more attractive in its performance, and more accessible, usually, as well. Those feedbacks really help to create a self-propelling change.

SP: What do you hope people will take away from knowing there are these positive tipping points and not just negative ones?

TL: I want people to take away a sense of empowerment or agency. There are demonstrated cases — loads of them that I touch on in the paper — where, at different scales, individuals, households, communities have come together and worked with the feedbacks that are in nature to positively tip to a better state.

SP: You write in the article that it took more otters to bring back the kelp forests on the West Coast than there were to begin with. With that in mind, how difficult is it to reverse a negative tipping point?

TL: If you want to tip back [to a nature-positive state], you've got to get to the point where you destabilize the undesirable state or give the system a big shove. It's that idea of alternative stable states [such as a thriving coral reef or a seaweed-choked one] that always tends to bring with it this quality that you have to work harder to positively tip recovery, in terms of the drivers, than to get the bad state. And that was true, for example, for the nutrient loading of shallow lakes in the Norfolk Broads. If you dial the phosphorus runoff back down again to the level at which you tipped the creation of this horrible eutrophic stew, I'm afraid you wouldn't get the system back; you have to dial it a lot further.

Mathematically, we talk about these alternative stable states having attraction; they maintain themselves, so you have to break the feedbacks that are self-maintaining for the bad state, just like the ones for the good state eventually got broken. But then, when you have tipped recovery, the good thing to know about is that that has its own irreversibility. It cuts both ways.

SP: Which negative tipping points are you most concerned about?

TL: The collapse of the great Atlantic Meridional Overturning Circulation, or AMOC for short, is my greatest source of concern because of the carnage that would cause for societies all over the world, but not least in the U.K., where I live. In the biosphere, I would say that our report [showing] that we may already have passed a tipping point for widespread coral reef dieback is pretty concerning. I guess I might be even more concerned if I felt we were reaching the tipping point to lose the Amazon rainforest or large parts of it. The coral reefs one is pretty bad, when you think about it from both the biodiversity point of view (it's at least a quarter of marine biodiversity) and the human point of view. Estimates differ, but there are always hundreds of millions of people who depend on these reefs for their livelihoods, so that's a huge issue.

SP: Do you think geoengineering could help us reach some of these positive tipping points?

TL: I think we should keep researching the global geoengineering possibilities to know what they're capable of and what their limitations and side effects are. But before we consider that, we should do everything in our power to do the things we know will work to accelerate the change to zero emissions to stop the underlying problem.

In the space of nature, there is no magical geoengineering solution for stopping the fundamental driver of people, on average, eating more meat, which is leading to the net destruction of nature. So again, let's focus on what it takes to change the crucial drivers, because the geoengineering only really matches up against things that are threatened by the rising temperature.

SP: What can individual people do to help trigger positive tipping points?

TL: Anyone can ask themselves about their dietary choices. I'm not saying everybody needs to go vegetarian or vegan, but just by reducing particularly our red meat consumption, we can [create] a disproportionate benefit for nature. We might all be inspired to be part of some nature-regenerating activity or initiative in our locale. Maybe we're part of a community garden movement; maybe we get a bit involved with wildlife trusts or something in replanting or regenerating the ecosystem. If those initiatives think about the amplifying feedbacks that they can activate to help the initiative spread, then being part of those could be the seeds of wider change. And loads of people already are part of those initiatives, which is great to see.

Editor's note: This interview has been condensed and lightly edited for clarity.

Something strange has been swirling in the waters around Antarctica. From the 1970s until a decade ago, the floating sea ice that radiates from the continent had been expanding, even with climate change already in full swing. Then, in 2016, it suddenly and dramatically contracted — and has yet to recover — as rising global temperatures seemed to catch up with the Southern Ocean. Far from being just a local issue, the loss of sea ice has huge implications for Antarctica's vast ice sheet, which would drive sea levels up 190 feet if it disappeared.

Now, scientists say they've identified what's behind this rise and sudden fall, thanks to an assist from deep-diving robots. It all comes down to salinity, winds, and churn. "One of the key takeaways from the study is that the ocean plays a huge role in sort of modulating how sea ice can vary from year to year, decade to decade," said Earle Wilson, a polar oceanographer at Stanford University and lead author of a new paper describing the research.

Doing the grunt work here was a network of data-gathering machines known as Argo floats. Torpedo-shaped and about the size of a human, they sink thousands of feet, sampling things like temperature and salinity, before popping back up to the surface and transmitting all that data to a satellite. Because they float passively, the instruments could for years gather data about how conditions were changing.

Now, forget about robots and think about swimming in a lake. When you dive, you're hit by a sudden rush of cold water. That's because the sun warms the surface, while the depths stay cool. This also happens in the world's oceans, though obviously the cold water goes much deeper.

The opposite happens in the waters around Antarctica. Because it's so cold down there, the air cools the ocean surface, while warmer waters swirl below. (Argo robots could detect this in fine detail as they ascended and descended.) With warmer liquid kept away from the surface, more sea ice can form.

As sea ice expanded in the decades before 2016, increased precipitation made surface waters fresher, in contrast to saltier waters below, resulting in stratification. (The saltier a liquid is, the denser it becomes.) This trapped the warmth in the depths, allowing it to build up.

Then the atmosphere played yet another trick, as winds intensified and shifted. This pushed surface waters away from Antarctica and churned up that deeper warmth. "What we witnessed was basically this very violent release of all that pent up heat from below that we linked to the sea ice decline," Wilson said.

This bluster was likely driven at least in part by climate change: As the planet warms, the atmosphere develops temperature gradients, which strengthen winds and change their patterns. Scientists, though, are still working out how much of this shift might be due to "natural variability," or what might happen anyway if humans hadn't released so much carbon since the Industrial Revolution.

Either way, the system shifted around 2016. Beyond bringing up warm waters, all that wind may have broken up the ice, both by pushing blocks together and by creating waves. "Recent research has shown that both atmospheric and oceanic warming is likely contributing to the sudden change in Antarctic sea-ice extent since 2016, and this paper helps to further develop the point that deeper ocean warmth is a significant player," said Zachary Labe, a climate scientist at the research group Climate Central who studies Antarctic ice but wasn't involved in the paper.

As sea ice has declined, it has imperiled far more ice elsewhere. The Antarctic ice sheet that rests on land is bolstered by ice shelves that float along the coast. These essential supports are already in serious trouble as warming seas and violent underwater storms erode their bellies, weakening them. If they also lose the sea ice floating around them, they lose a significant buffer, as the floating chunks absorb wave energy. In addition, a healthy amount of sea ice is quite bright, meaning it reflects a bunch of the sun’s warmth into space, reducing local temperatures. Because the ice shelves hold back the ice sheet, losing them would mean an accelerated decline of an extraordinary amount of frozen water sitting on the continent.

While the Argo floats provided invaluable data, scientists are scrambling to get still more measurements. "Overall, we need more international support to continue building observing networks across the Antarctic polar region, both for oceanic and atmospheric monitoring," Labe said. "This is critical given the rapid changes we are beginning to observe in this part of the world in a warming climate, with potentially significant consequences for global sea level rise."

The big question now is whether we're witnessing a permanent state of low sea ice, or whether atmospheric and oceanic conditions might swing back enough to encourage years of growth. The promise of this new research is that it will help researchers refine their models to predict how much the waters around Antarctica might change, and how quickly. Perhaps sea ice will see years of sharp decline, followed by years of growth. "But the long-term, multidecade trend will be negative," Wilson said. "That would be my guess, but we don't know for sure."

This story was originally published by Grist. Sign up for Grist’'sweekly newsletter here.

It's now clear. Scientists predict that humanity will miss its target of keeping atmospheric warming to 1.5 degrees Celsius above pre-industrial times, with the globe sailing into an even warmer future. And the impacts of this warming are escalating, from extreme weather disasters and hits to biodiversity to melting glaciers and sea level rise.

So: How high will our temperature go? How long will it stay at its peak before cooling back down? And what will this mean for our planet?

The 1.5 degrees C target was originally set by a landmark, legally binding international agreement back in 2015, at the Paris meeting of the Conference of the Parties (COP) of the United Nations Framework Convention on Climate Change (UNFCCC). The Paris Agreement aimed to reduce greenhouse gas emissions rapidly and hold the planetary temperature rise to well below 2 degrees Celsius, while pursuing efforts to limit the warming to 1.5 degrees C.

This became the guiding star of global action to fight climate change, with wide acknowledgement that the higher the warming, the higher the harms to ecosystems, human health, food supplies and other aspects of planetary well-being.

Yet now, more than a decade later, nations' cumulative actions and commitments on emissions are falling far, far short of what's needed to meet the Paris Agreement goals. Complicating matters, the United States pulled out of the agreement in 2020 and again in 2026 — the only one of the original 195 parties to do so.

One of the sticking points in international negotiations has been reaching consensus on fossil fuels. Controversially, the 2015 Paris Agreement didn't even mention fossil fuels — a political concession designed to keep fossil-fuel-rich nations on board. But it has long been clear that cutting emissions and stopping warming means moving away from carbon-based fuels: Today, burning fossil fuels for energy is the source of about three-quarters of global greenhouse gas emissions.

It wasn't until the 2023 meeting of the UNFCCC that parties officially called for a transition away from fossil fuels. Disappointingly, though, despite a push from some nations, the most recent 2025 meeting ended without a hoped-for roadmap for a fossil fuel phaseout. In response, a coalition of countries has made plans for a First Conference on Transitioning Away from Fossil Fuels. Representatives of more than 50 nations will meet in Colombia at the end of April, as part of an attempt to forge a "fossil fuel treaty" to fast-forward the world's adoption of renewable energy and chart a path away from coal, oil and gas.

Whatever happens with our emissions pathway next will play a huge role in determining the peak amount of warming the planet experiences — whether that’s 1.7 degrees C above pre-industrial times, 2 degrees, 2.6 degrees or more — and if and how fast people can pull that warming back down again.

Andy Reisinger, a climate change researcher and independent consultant who serves on He Pou A Rangi, the New Zealand Climate Change Commission, has studied these issues. A longtime contributor to the Intergovernmental Panel on Climate Change (IPCC), he has helped map out the various ways the world might exceed but then return to 1.5 degrees C of warming. Reisinger recently coauthored a 2025 Annual Review of Environment and Resources paper that explores the concept of climate overshoot.

This conversation has been edited for length and clarity.

How much warming has our planet seen so far?

2024 was the first calendar year when global average temperature exceeded 1.5 degrees C above the late 19th century average. But global warming is usually defined as the average temperature over at least two decades, because temperature varies naturally from year to year. Right now, the best estimate is that we're a little bit over 1.4 degrees C of global warming. It's very likely that we're going to surpass 1.5 degrees C of warming within the next 10 years and possibly even within the next five.

What are some of the impacts of that warming so far?

We've seen over the last few years really damaging climatic extremes in the form of heat waves, floods, wildfire, very intense droughts in some regions. The harms include loss of human life, severe economic damages and long-lasting hits to ecosystems. Sea levels have continued to rise; the rate of that rise is now double what it was during the 20th century.

We've seen the first officially recognized climate refugees arriving in Australia from the Pacific Island nation of Tuvalu. We've also seen extremely damaging hurricanes and other intense tropical storms. Of course, there's always the question: Well, is that climate change? There's increasing evidence that some of those extreme events would not have been possible at that intensity without global warming.

What do the best computer simulations show about how warm the planet will get?

The climate system is like a super tanker or a freight train: Even if you slam on the brakes as hard as you can right now, this will not instantly stop the warming. It will slow it down. But it will take decades, even if we go all out, to bring emissions down to a level that will halt the warming entirely.

According to models, there's at least another 0.3 degrees C of global warming in store simply because we cannot stop carbon dioxide emissions overnight, which means the best chance we have is to limit warming at 1.7 degrees C. As a rule of thumb, every five years of ongoing emissions at current levels adds another 0.1 degrees C to peak warming. Time is not on our side.

As the world warms further, many weather extremes are expected to get worse or more frequent. Will some systems hit a breaking point?

There's good evidence that tropical coral reefs will become largely unviable beyond a critical threshold. We're seeing increasing severe bleaching of major coral reef systems all around the world now. If warming rises to 1.7 degrees C, there is a very good chance that widespread, healthy coral reef systems will no longer be able to function. This doesn’t mean that corals will go extinct; there’s chances for survival in smaller pockets. But the Great Barrier Reef is very unlikely to survive.

A key tipping point that's attracting increasing attention is the Gulf Stream, which carries warm water into the high latitudes in the Atlantic. Some, but not all, models predict potential for an abrupt shutdown, irreversible for many generations, which would have dramatic consequences. It's not just that suddenly the Norwegian fjords freeze over, but there would be widespread changes to rainfall, and challenges to agriculture through rapid cooling and drying.

Countries are waking up to this existential risk. A recent study hints at an increased probability of this happening; but models are still unable at this point to say that the Gulf Stream will dramatically collapse at precisely x or y  degrees of warming.

There's a whole range of feedback systems kicking in, including the release of planet-warming methane from tropical wetlands — the more the world warms, the more methane is released, which warms the world even more. Are these feedbacks well-behaved? Do they scale up gradually with global warming? Or do they accelerate?

When talking about corals, you said "if" the world warms by 1.7 degrees C. But isn't that a certainty now?

Yes [laughs]. I mean, that's my mental-health-saving mechanism. It's only "if" in the sense that it hasn't happened yet.

Will we stay below 2 degrees C, the upper target mentioned in the 2015 Paris Agreement?

I wouldn't want to give it a probability. On the positive side, if you look at every emissions target that any politician ever uttered, if you add all of those up, you would limit warming to about 1.8 degrees C. However, that includes pledges that have very little credibility, with no plans or policies to actually deliver on them. If you only look at policies as they currently are, you end up with warming at around 2.6 degrees C as the best estimate.

What will it take to stay below 2 degrees C warming?

We know what to do. It requires, mainly, displacing the use of fossil fuels with electricity and generating that electricity with renewable sources. The good news is that we see a rapid expansion of renewables through solar and wind all around the world. The bad news is those currently meet the increasing demand, but they don't displace existing fossil fuel generation. What needs to happen is a very rapid phasedown, and ultimately phaseout, of the use of fossil fuels to generate electricity, including an accelerated decommissioning of existing fossil fuel infrastructure.

One area that gets less attention is agriculture, which is a major source of methane, and is also linked to increasing carbon dioxide levels through deforestation. Halting deforestation by 2030 is key.

It's a massive endeavor, and yet we can envisage a world with these changes — it's not science fiction.

Should we simply set a new, higher target for an acceptable amount of warming — or should we still fight to return to 1.5 degrees C, even if the temperature peaks higher than that for a short while?

There's an emerging narrative from some people who say, "Well, 1.5 degrees C was always only an aspiration and overly ambitious goal. Now that that's no longer on the table, we can go to more pragmatic policies." That fundamentally misconstrues the issue. The urgency has not decreased. It has increased.

I think it would be deeply problematic to simply say, "Oh, well, 1.5 is gone. Let’s now aim for 1.8." One, what makes you think we'd meet that target? But also, the International Court of Justice last year issued its landmark opinion that 1.5 degrees C is an enduring objective, and that countries are legally obliged to try to limit global warming to it.

We are going to lose millions of people through heat waves, through the consequences of flooding, through malnutrition and drought, if we simply live with a warmer world. We have enough evidence to think that a sustained warmer world is deeply more damaging and risky than a world that reaches some peak warming level temporarily and then brings the temperature back down again.

Once the world temperature peaks at, say, 1.7 degrees or 2.6 degrees C, how hard will it be to return to 1.5 degrees C?

The scale of this challenge is huge, whether you predominantly aim to achieve it by increasing carbon dioxide removal (by planting trees or using industrial processes to suck carbon dioxide out of the air), or through further reductions of carbon dioxide or methane emissions. We need all these things.

The effort needed to bring temperature back down again goes beyond the effort needed to hold global warming at a set target. The best estimate currently is that you need to remove a net of 220 gigatons of carbon dioxide from the atmosphere for every 0.1 degree Celsius of cooling.

Global afforestation — tree planting — around the world delivers about two gigatons of carbon dioxide removal per year. So, if we could halt all deforestation tomorrow, if we stopped all fossil fuel use, and persisted with the current level of afforestation, it would take 100 years to bring temperature down by 0.1 degrees Celsius.

If we don't limit warming to 2 degrees C, there's no way we're going to bring it back to 1.5 degrees C within a reasonable time horizon.

Are there risks involved with trying to reverse warming quickly? Can it be done in a just way, by which people mean a fair and equitable way?

Policies that aim to achieve that and are not well implemented clearly bring major risks in their own right. The use of land to achieve carbon dioxide removal, by planting trees for example, could compete with land for food production. It could displace people whose livelihoods rely on the land. And it could pose severe threats to ecosystems.

I think we know in theory how to manage these risks. The question is, will the real world implement such policies in light of that evidence, or will it run roughshod over calls for a just transition? That’s the space where there’s concern.

You have done a lot of work on reports of the IPCC. Is that organization, which synthesizes current climate science for policymakers, still relevant?

The IPCC remains a vital reference point for what we actually know. What's relevant about the IPCC is shifting: Ten years ago, the question was still, "Is it true that we are changing the climate?" The IPCC found that all of the global average temperature change we've seen over the last 150 years was caused by humans. People didn't contribute to it. They caused it.

Now the interest is more and more shifting to the solution space. The IPCC is still vital, but it's clearly not the only game in town. There are other bodies, like the International Energy Agency, like various NGOs, that say "Here's a whole smorgasbord of solutions." But the IPCC is important because it's the one without an inherent financial motive.

We've seen increasing pushback from countries that are reluctant to acknowledge the IPCC as an authoritative evidence base. And of course, the IPCC is run by humans. It isn't fault-free. But it's the best we have by far.

Have you been encouraged or discouraged by the UNFCCC COP meetings?

COP meetings are clearly political processes: The outcomes are not dictated by facts. Some countries have deep and not illegitimate concerns that, for them, the cure may be worse than the disease.

It's been striking how countries have repeatedly agreed at COP meetings, in the meetings' conclusions, to want to keep the 1.5 degrees C target alive, to not let it go. This is why the topic of overshoot is really important. If you want to keep 1.5 degrees C alive, the only path is now up to a peak warming of greater than 1.5 degrees C and back down again.

I don't see very high chances of the COP meetings actually agreeing to a full fossil fuel phaseout. But let's be clear, the immediate need is for a rapid phasedown of fossil fuels, and even that has been a challenge to get commitments on.

What about the pushback, especially from the United States, on green energy policies and continued support for fossil fuels — including US incursions into oil-controlling nations, like Venezuela and Iran?

The push towards renewables is unstoppable because it's in a country's self-interest. The war in Iran has made that clear. Through reduced fossil-fuel dependency, through reduced price volatility, through increased resilience in case of supply shortages, through reduced health costs from air pollution. All those things add up. You don't have to have an altruistic motive to want to get out of fossil fuels.

You can't run a world superpower on coal. I'm confident of that. The acts of the current US president are not a guide for the long-term future.

The First Conference on Transitioning Away from Fossil Fuels is due to be held at the end of April, co-organized by Colombia and the Netherlands. Is this meeting going to make a big difference, or is it largely symbolic?

It can be a shining beacon even if it's only symbolic. These are diverse countries coming together, including many Pacific Island nations as well as Cambodia, Kenya, Chile, Australia, Denmark and others. Having a forum where you talk through, with a wider group of countries than you might ordinarily call "like-minded," what we need in order to ensure the energy transition is a just transition that protects the most vulnerable — to talk about it aloud, is a really important initiative, even if it comes to nothing. It prepares the ground. That's especially the case in a time of rising authoritarianism.

But I think it's really important to hold onto multilateral institutions like the Paris Agreement and COP meetings, because they are what give voice and power to small countries. Yes, they may be ineffectual. Yes, they can be used and misused through veto and strong special interests. But it would be, in my view, problematic to retreat from multilateralism entirely.

You can certainly complement the multilateral process with narrower initiatives that try and push the ground forward. That can widen the space that multilateral activities can then grow into.

Do you have kids? What do you hope will happen in their world?

We've got one child, a son. For me, the most startling thing is that he, in all likelihood, might be alive in the year 2100. Despite my work in climate change and climate change impacts, I can't help but admit that the year 2100 and the impacts that the world might experience by then is a highly abstract concept.

I cannot deeply visualize and emotively embrace that world. Having a son who may live to see that world is a shock to the system, because it makes it so much more real than any computer model.

My hope is that he will live long enough to see a world that has started on our road to recovery from peak warming. Whether we get back to 1.5 degrees C in his lifetime is highly questionable, but the idea of him seeing the ship being turned around is my strong hope.

As for you and I, these are the coolest summers we will live through. Every other summer in the rest of our lives will be warmer. We will not see the recovery in our lifetime, and that’s something to swallow. But it’s our job to ensure that he can.

This article originally appeared in Knowable Magazine, a nonprofit publication dedicated to making scientific knowledge accessible to all. Sign up for Knowable Magazine’s newsletter.

Eight U.S. East Coast cities are at high or very high risk of "extreme" flood damage based on current scenarios, with New York and New Orleans facing some of the greatest dangers, a new study finds.

New York could see the highest number of people affected by flooding: 50% of New York City's population ‪—‬ around 4.4 million people ‪—‬ and 47% of its buildings are currently at high risk of exposure to extreme flood damage if a major flood occurs, according to a flood risk assessment published Wednesday (April 22) in the journal Science Advances.

New Orleans faces the greatest relative risk, with 98% of its population ‪—‬ about 375,000 people ‪—‬ and 99% of its infrastructure at high risk of being exposed to extreme damage, according to the study.

The other six cities mentioned in the report are Houston; Miami; Norfolk, Virginia; Charleston, South Carolina; Jacksonville, Florida; and Mobile, Alabama.

The heightened threat and damage levels these cities face result from their low elevation, high population density, poor drainage, building height, rainfall and proximity to water. The study authors urged policymakers to work with local stakeholders to mitigate flood risk using nature-based solutions alongside structures like floodgates, levees and dikes.

"Such policies should restrict further urban development in high-risk zones while promoting the systematic incorporation of nature-based solutions," the authors wrote.

Flood risk

Flooding is the most expensive natural disaster in the U.S., costing billions a year. By 2050, sea levels along the contiguous U.S. coastline are projected to rise by up to 1 foot (0.3 meters), and flooding following hurricanes is also increasing along the East Coast due to climate change.

With around 30% of counties along the U.S. Gulf and Atlantic coasts at high flood risk, it's essential to understand which measures will prevent flood damage most effectively, the authors wrote in the study.

The researchers used machine learning to assess flood risk along the U.S. East Coast, using historical flood damage data from the Federal Emergency Management Agency. This data is of visual, bird's-eye-view damage to properties associated with recent major flooding events, including Hurricane Isaac in 2012 and Hurricane Irma in 2017. The study classified properties that were fully destroyed as "extreme flood damage."

The team then compiled data on 16 flood risk factors and developed a flood risk map, using these risk factors to predict exposure to flood damage The flood risk factors included natural hazards, such as distance from the water and elevation; exposure factors, such as population density; and the vulnerability of the population, such as the percentage of people living in poverty.

Based on these factors, the model produced a "flood risk index" of probability scores ranging from "very low" to "very high" risk. The coastal cities at the highest risk of floods leading to extreme flood damage could then be estimated. The team calculated the number of people and buildings that would be exposed to this damage.

The results showed that New York City and New Orleans share the "grim reality" of being "major flood-risk cities," the authors wrote in the study. Almost 4.4 million people in New York City and over 215,000 buildings could face extreme flood damage. Over 98% of New Orleans' population and buildings face similar damage.

Houston and Mobile, Alabama, are also at high risk of extreme flood damage, so, along with New York and New Orleans, these cities demand "prioritized attention from policy-makers," the authors wrote in the study.

The authors noted several ways to potentially reduce flood damage. For example, parking lots built with impermeable concrete should be replaced with grass tiles to allow the soil to soak up the water, and wetlands and river floodplains should be restored and linked to drainage systems like gutters to support the fast removal of water from cities.

Catastrophic water shortages are in store for the 40 million people living in areas fed by the Colorado River, even if cities in the region such as Denver, Phoenix and Las Vegas make dramatic cuts to their usage, recent research suggests.

Water shortages could start as soon as this summer, as snowpack levels reached a record low over Lake Powell and the spring runoff into the Colorado River is expected to be minimal, experts told Live Science. And the region's major cities, which have already slashed their per capita water consumption by up to 58% between 2002 and 2025, can't solve the problem alone.

"We can't just shove it all onto the residents of these cities and tell them to use less water, because it's still not going to be enough [to prevent water shortages]," Renee Obringer, an assistant professor in the Department of Energy and Mineral Engineering at Penn State and the first author of the new study, told Live Science. "Regardless of what mitigation we do, we're still going to have to adapt to this warmer world that is going to have more intense droughts and more frequent droughts."

The findings reveal that bolder measures will be needed to head off disaster in the Colorado River basin. But exactly what are those steps?

One piece of the puzzle

Seven states — Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming — pull water from the Colorado River, and the amount allocated to each region is governed by a century-old document called the Colorado River Compact.

But the Colorado River basin, along with the rest of the U.S. Southwest, has been in a megadrought for 25 years. Between 2000 and 2019, the river's flows shrank by 20% due to climate change and water overuse to supply cities, agriculture and industry.

Finding new water supplies is unlikely, so Obringer and her colleagues analyzed what would happen if three large cities fed by the river — Denver, Las Vegas and Phoenix — reduced their consumption by around 25% under various climate scenarios, ranging from a global temperature increase of about 2.9 degrees Fahrenheit (1.6 degrees Celsius) to an increase of 7.7 F (4.3 C) compared with preindustrial levels.

Their results were published in December 2025 in the journal Water Resources Research. In most climate scenarios, demand management — which encompasses broad strategies such as raising awareness, offering rebates, and subsidizing low-flow devices — did not make up for lower water storage in urban reservoirs caused by higher temperatures and lower precipitation in the region. Denver, which is technically not located in the Colorado River basin but gets half of its water from the Colorado River, was the lone exception. Demand management compensated for river flow reductions in two high-emissions climate scenarios for the city. However, Obringer suspects some of those more optimistic results could be an artifact of the way the model handles uncertainties.

Cities fed by the Colorado River basin have reduced water use through programs aimed both at demand and reuse. In Las Vegas, for example, residents receive cash rebates for replacing water-heavy lawns with desert plants. The city, which gets 90% of its water from the Colorado River, also returns, after treatment, 40% of the water it uses to Lake Mead, where it can then be reused.

Cities have taken significant steps to reduce their footprint, and they will likely continue to improve, said Brad Udall, a senior water and climate research scientist at Colorado State University’s Colorado Water Center who was not involved in the study. As a result, some of the region's biggest cities use less water per capita than they did a few decades ago.

But the more efficient cities get, the fewer opportunities they will have to save and reuse water, Udall told Live Science.

Bigger water users

The results highlight a reality scientists have long known: Demand management alone cannot offset the Colorado River's dwindling flows, said Sharon Megdal, a professor and director of the Water Resources Research Center at the University of Arizona, who was not involved in the study.

Cities make up only 18% of water use in the region, while agriculture guzzles more than 70% of the basin's water. "Agriculture's the big user," Megdal told Live Science.

"You can't solve this problem without dealing with agriculture in a major way," Udall agreed. "Because agriculture is 70% of the problem, it needs to be at least 70% of the solution."

Individual farmers have senior water rights to Colorado River water, meaning they receive their full allocation regardless of whether there is a shortage, but political pressure is rising to allocate more water to cities and cut farmers' consumption, Udall said. For example, water managers may decide that farmers in Arizona have to relinquish water to supply the Central Arizona Project canal, which delivers water from the Colorado River to the central and southern parts of the state, including Phoenix and Tucson.

Since 2019, the Colorado River has shrunk so much that it is now 35% smaller than it was on average in the 20th century. "We've never seen flows like this," Udall said. "If these flows continue to drop, I do see agriculture in the Lower Basin not getting the supplies they do [now] and those supplies being reallocated to cities."

The problem is that farmers in the Lower Basin grow crops that benefit the region economically through exports, including alfalfa, cotton, vegetables and citrus fruit. In Arizona, roughly 20% of cropland is used to grow alfalfa for cattle feed. The state is also the biggest cotton producer in the Colorado River basin, and it grows up to 90% of leafy greens consumed in the U.S. and Canada.

To cut their water consumption, farmers can change their irrigation techniques and crop patterns, Megdal said. Drip irrigation, which delivers water directly to the roots, cuts evaporation and reduces water use by up to 50% compared with methods such as flood irrigation used for cotton and alfalfa. Thirsty crops such as alfalfa could be replaced with low-water forage mixes consisting of wheat, barley, oats, rye and peas. Recently, there has also been a focus on guayule, which is a substitute for rubber, as an alternative crop for farmers, Megdal said.

But farmers respond to demand and may have long-term contracts with buyers. "It has to be economical," Megdal said.

Agriculture should switch to more efficient irrigation, but it's also important to realize that some seemingly wasteful methods, such as furrow or flood irrigation, can replenish aquifers, which are also being depleted, Udall said.

Some farmers are letting their fields go fallow, which could happen more and more as water shortages intensify, Megdal added.

Renegotiating water rights

The Colorado River Compact is up for renewal this year, meaning there is an opportunity to devise a more sustainable agreement, Obringer said. But negotiations have stalled between the Upper Basin, which includes Colorado, New Mexico, Utah and Wyoming; and the Lower Basin, which encompasses Arizona, Nevada and California. While officials wrangle over the precise wording in the document, the underlying problem is that the Lower Basin needs more water than it's getting, even though the Upper Basin already uses less water than it was allocated in the compact.

Officials in the Upper Basin have argued that cuts should now fall exclusively upon the Lower Basin. But that can't happen, Udall said, because cuts need to be deep across the Colorado River basin to make a difference. No matter what the Upper Basin thinks it is entitled to, it must accept reductions in water use, he said.

Reality check

Solutions must be found and implemented immediately, because the Colorado River's future has never looked bleaker.

Winter brought barely any snow, and the little that fell melted in early March instead of April, meaning river flows this spring and summer could hit record lows. "It's unprecedented; it's human-caused; it's scary, frightening, awful," Udall said.

Udall estimates that Lake Mead, which serves almost 25 million people in cities such as Las Vegas and Los Angeles, and Lake Powell, which supplies Lake Mead and Indigenous tribes, will be only about 20% full over the coming months. Without adjustments in reservoir release, water levels could drop low enough to prevent energy production at Glen Canyon Dam, which usually produces enough electricity to power over 350,000 homes.

"We're close to dead pool," Udall said. This is when the water level in a reservoir falls so low that it can't flow downstream. "That's never happened, and it's very serious."

It would take years of unusually high precipitation and runoff to recover from the current state, according to Megdal. "It is a challenging situation," she said. "You really have to adjust to a new normal."

To make matters worse, "data centers are popping up everywhere in this region," Obringer said. A midsize data center uses up to 300,000 gallons (1.4 million liters) of water per day for cooling, and this number will only increase as temperatures rise. Much of the water that runs through the system can be reused, but some is consumed to generate the electricity to power data centers.

Some small steps to mitigate the problem are already in the works. Some municipalities are buying water rights and groundwater from rural areas in the region, Megdal said. For instance, the rapidly-growing town of Queen's Creek, Arizona, is purchasing groundwater from farmers and investors in the sparsely populated Harquahala valley. Arizona is also drawing up agreements with California and Mexico to obtain desalinated water.

"I do think there's a tremendous capacity to adapt," Megdal said.

But a more durable solution will require a major overhaul of the existing agreements and water rights to reflect reality, Udall said.

"We've got to have an agreement on how to share the water we have and not pretend we live in the past," he said. "We need to adjust this system to deal with a completely new reality of much less water flow. We've got to balance the books here."

Atlantic Ocean currents that are vital for keeping Earth's climate in check will halve in strength by 2100 and may be closer to collapse than first thought, a new study finds.

The Atlantic Meridional Overturning Circulation (AMOC) acts as an oceanic conveyor belt, circulating warm water north from the tropics and cold water south. This regulates climates across Europe, Africa and America while also sustaining aquatic life.

Now, a study estimates the AMOC will slow down between 43% and 59% by 2100 — a 60% stronger weakening than past models predicted. The research corrects for biases in previous estimates by including the temperature and saltiness of the Atlantic Ocean's surface, according to the study published Wednesday (April 15) in the journal Science Advances.

This "more substantial AMOC weakening" means that a critical planetary system is closer to a tipping point — an irreversible "point of no return" for the climate — than many past models suggest, the authors wrote in the study.

However, other experts note that the predicted magnitude and speed of an AMOC slowdown varies greatly from study to study.

"In my opinion there is a need to interpret new results for each study into a wider context," María Paz Chidichimo, an expert on ocean circulation at the National Scientific and Technical Research Council (CONICET) and National University of San Martín in Buenos Aires, Argentina, told Live Science in an email.

"Studies predict AMOC decline on a range from small decline to large decline, but I think the magnitude and timing of AMOC decline are still uncertain given the large spread in model projections," she added.

Laura Jackson, an expert in North Atlantic ocean currents at the Met Office in the U.K., agreed. "It is still an open question as to which model AMOC projections are most likely," she told Live Science in an email.

Catastrophic collapse

An AMOC collapse would last for hundreds to thousands of years and have catastrophic consequences. It would send temperatures in northern Europe plummeting while southern Europe experiences extreme droughts. The sea level would rise along the northeast coast of North America. Disruption would spread across food webs and ecosystems in the ocean and on land — for example, the amount of land available for growing wheat and maize, which supply two-fifths of global calories, would be cut by more than half.

Modeling the AMOC slowdown

Observations reveal that the AMOC has weakened compared with its 1850 to 1900 baseline. Previous research has attempted to estimate the strength and pace of the AMOC slowdown, with some studies finding minimal weakening by the end of the century while others predict an imminent collapse.

However, because continuous AMOC monitoring only began in 2004, few previous studies have included real-world observations in their calculations. And where real data has been used, most studies only incorporated a single observable variable, such as past AMOC strength or average seasonal temperature changes, the authors wrote in the study.

Yet since AMOC is a complex system, multiple observable variables should be considered in climate models, the authors wrote.

In this new study, the researchers used different statistical methods to compare the performance of various climate models that project an AMOC based on different emission scenarios, evaluating which was most accurate at predicting the future AMOC's slowdown.

The scientists found that the most accurate model paired sea surface temperatures and salinity across the Atlantic with a statistical method rarely used in climate modeling. This method, called "ridge-regularized linear regression", reduced the prediction error of the model by 79% compared with the standard modeling approach.

This model estimated that AMOC will slow by around 51% from its 1850 to 1900 average. The Intergovernmental Panel on Climate Change's (IPCC) 2022 report called a 50% AMOC slowdown a "substantial weakening."

"This is a key result with implications for the future climate of the Atlantic and beyond," the authors wrote in the study.

While these results are not particularly surprising, the finding that "the projected weakening is larger than previously thought is clearly worrying," David Thornalley, a professor of ocean and climate science at University College London in the U.K. who was not involved in the research, told Live Science in an email.

The predicted AMOC is "so weak that it is then very likely on the way to full shutdown," Stefan Rahmstorf, a professor of ocean physics who heads the Earth system analysis department at the Potsdam Institute for Climate Impact Research in Germany, told Live Science in an email.

Even so, experts told Live Science that AMOC model estimates are largely driven by which variables are included in the analyses, so results can vary. And although the new study corrects for previous biases, there "remains uncertainty in how well models can simulate and predict changes in the AMOC," Thornalley said.

Focusing too heavily on an AMOC collapse may not be the most helpful path forward, Chidichimo said. "We have enough scientific evidence of AMOC variability and slowdown, and we are already experiencing environmental changes associated with AMOC change which have important socioeconomic impacts worldwide," she said. "Nations need to prepare now."

Something surprising has been happening to polar bears. Those living in Svalbard, a Norwegian archipelago, have been gobbling up hundreds of birds' eggs and looking healthier than they have in the past. And in warmer parts of Greenland, the bears are showing signs of genetically adapting to climate change.

The discoveries seem to be unexpected bright spots for the beleaguered species, which for decades has been photographed clinging to vanishing sea ice and has become a "poster animal" for the effects of climate change. So what do the promising signs mean for polar bears? Could they actually survive the rapid melting of Arctic sea ice?

Experts told Live Science that the new findings show there may be unexpected refuges where some polar bear populations cling on or even do well for longer than models suggest. Alone, these discoveries won’t be enough to save polar bears from extinction, but they might buy these iconic creatures a little more time as the world attempts to do the one thing that could save them — cutting emissions.

An icebound creature

The future for polar bears (Ursus maritimus) has looked precarious for a long time. The animals depend on sea ice, on which they hunt ring seals (Pusa hispida) and bearded seals (Erignathus barbatus), which can outswim the bears in the water. As the climate warms, sea ice is melting, shrinking this key hunting ground. A 2020 study projected that if greenhouse gas emissions continue as usual, all but a few polar bear populations will collapse by 2100, with the remaining ones clinging on for longer in a handful of "last refuges" such as the Queen Elizabeth Islands, Canada's northernmost Arctic archipelago.

Yet the recent positive findings raise the tantalizing prospect that polar bears might be able to survive climate change after all.

A January study in the journal Scientific Reports looked at the body condition of 770 adult polar bears in Svalbard between 1995 and 2019. They found that, on average, the bears became thinner until 2000 but grew fatter afterward, despite a rapid loss of sea ice there.

That was a surprise, because a fat polar bear is a healthy one, lead researcher Jon Aars, a research scientist at the Norwegian Polar Institute in Tromsø, told Live Science. "We expected to see a decline in body condition because of the rapid loss of sea ice."

And a study published in the journal Mobile DNA in December 2025 revealed that polar bears in southern Greenland are using "jumping genes" to rapidly rewrite their own DNA, potentially allowing them to more readily adapt to warmer habitats by changing how they handle heat and process fats.

Mixed picture

So do these findings really mean the picture is looking less bleak for polar bears?

Andrew Derocher, a biologist at the University of Alberta who worked with Aars on the Svalbard bear study, told Live Science that there are 20 unique polar bear populations around the Arctic, and each lives in a slightly different environment and faces a different level of sea ice loss.

"The basic premise is that if you lose the sea ice, the bears are losing habitat," he said. "They're forced on land for longer. They use up more energy, and then they get in poorer condition, with knock-on effects on survival and reproduction." But there is an incredibly productive ecosystem between the islands in the Svalbard area and those in the Russian Arctic near Franz Josef Land.

Because the area is on a continental shelf, the water off Svalbard is relatively shallow and warm, with nutrient-rich water flowing in from the North Atlantic, he said. This means polar bears have lots of prey options. They are eating walruses, birds and even birds' eggs, and they're staying in good shape.

"In dense colonies of ground-nesting birds like ducks and geese, bears have been seen taking a couple of hundred eggs during a single day," Aars said. "They just raid quite a lot of the nests, eating absolutely everything."

And although seal numbers in Svalbard are down, where there is ice, the seals sit on it in higher density, which may make them easier to catch, Derocher said. Sometimes the Svalbard bears have even been spotted catching reindeer (Rangifer tarandus platyrhynchus).

Unfortunately, there are not enough reindeer to sustain a population of polar bears, he said. "So, no matter how wonderful those pictures look when they're scarfing down a reindeer, it's not going to help them."

The new insights highlight polar bears' resourcefulness, said Louise Archer, a polar bear scientist at the University of Toronto Scarborough.

"What we're seeing happening in Svalbard is really interesting in terms of all the different behaviors that polar bears can employ to deal with their changing environment," Archer told Live Science.

But their shift to hunting birds' eggs, walruses and reindeer doesn't mean they are developing evolutionary adaptations to an ice-free world.

"They've always done that," Derocher said. "They're just being forced to do it more."

It's clear that a permanent land relocation is unlikely, because they move onto the ice as soon as it reappears, he added. "Sea ice is what makes a polar bear possible," Derocher said. "It's the high fat diet from the abundance of seals that allows them to exist in an incredibly cold environment."

Body condition also isn't the whole story, he said. Svalbard's polar bears may be in good shape, but they reproduce on ice. Because large areas of Svalbard's west coast are now free of sea ice, key areas in which they build dens have disappeared. A December 2025 modeling study estimated that reproduction and cub survival will decline around Svalbard in low-ice years. "The ice just doesn't come in time," Derocher said.

Genetic adaptation?

But is there hope in the news that some polar bears seem to be genetically adapting to warmer climes? Alice Godden, a bioscientist at the University of East Anglia, and her colleagues looked at genetic elements that can copy and paste and jump around the genome, causing mutations, in subpopulations of polar bears in northern and southern Greenland. They found more of this genetic activity in the southern population, where it is warmer.

Many of the changes in gene expression were in metabolic pathways that govern fat processing, so they could be reactions to warmer weather and a changing diet. It's a promising sign that the bears are adapting, Godden said, but the time scale required for such changes to make a meaningful difference is longer than the time polar bears are thought to have left.

The majority of the Arctic Ocean could be ice-free during summer by 2050, but as the length of a polar bear generation is about 11.5 years, genetic adaptations to an ice-free ecosystem will likely take many hundreds or thousands of years, Godden said.

"They're adapting as best they can, but without human intervention, the odds aren't looking great," she said.

Derocher, for his part, suspects the genetic changes may not be adaptations at all but rather a sign the bears are more stressed, which can lead to DNA damage and thus more mutations, essentially causing faster biological aging.

Patches of hope in an overall bleak picture

Ultimately, some polar bear populations may do better than others, depending on local geography, food availability and sea ice dynamics. "We suspect that it's going to be 20 different subpopulations, 20 different scenarios, all kind of following the same trajectory but at different sort of time scales," Derocher said.

Aars agreed. "I think the likely thing is that polar bears will disappear from much of the Arctic as sea ice recedes further and further north, but it's very, very difficult to say how fast it goes," he said.

Archer expects populations to plummet earlier in regions like Western Hudson Bay, Southern Hudson Bay and western Canada, which lacks a rich ecosystem and where bears already spend several months without sea ice.

But as the Svalbard news shows, there are potential refuges where the bears could hold out for longer. In other parts of the High Arctic, such as around the Canadian Arctic Archipelago, there is still very thick sea ice, which allows little light to penetrate to the water and therefore little energy to support a food chain. As this ice starts to thin, more algae will grow, supporting communities of invertebrates, fish and seals that can feed polar bears, which may allow them to remain in these areas beyond the end of the century, Archer said.

How long Svalbard could sustain a viable population of bears isn’t certain. “Are the Svalbard bears going to get hit by a devastating warm year next year, the year after, or can they go like this for 20 more years before things get really bad?” Derocher said.

Ultimately, the odds of these iconic bears surviving beyond the end of the century will depend mainly on reducing emissions. "There are some changes that are already baked into the system, but there's a lot that we can do to alter what the future looks like for them."

For example, if we limit global warming to 3.7 degrees Fahrenheit (2 degrees Celsius) above pre-industrial levels then adult polar bears could survive to 2100, even at the southern end of their range in Hudson Bay, Archer said.

“We are not on an unstoppable trajectory towards a tipping point where sea ice disappears for good,” Archer said. "It’s absolutely in our hands how the future plays out.”

Every state in the West is expected to face an above-normal threat of wildfire this summer, according to the latest projections, released Wednesday by the National Interagency Coordination Center.

The government-run center publishes monthly reports predicting fire risk for the four months ahead, and the change since the March outlook is staggering. The agency denotes elevated risk in red on its maps, and the June forecast from March 2 showed a small swath of rouge in the Southwest. But, citing an ongoing snow drought, rapid snowmelt, and a recent unprecedented heat wave, the latest maps feature red spilling across the Southwest and into the Rockies, Pacific Northwest, and northern California.

"We're probably not going to be in great shape this year," said Matthew Hurteau, director of the Center for Fire Resilient Ecosystems and Society at the University of New Mexico. While it's normal for the Southwest to experience a relatively early fire season, before the summer monsoons hit, what really stood out to him was how quickly the red moved north. "It's really early for that."

June typically sees snow lingering in many mountain ranges and snowmelt wetting the landscape, he said. Not this year.

The latest outlook reports that the snow melt-off in the Four Corners region came "not just several weeks or months earlier than normal, but also four to six weeks earlier than the previously recorded earliest melt-off dates." The recent heat wave also desiccated the West. Albuquerque, for example, recorded its earliest ever 90-degree reading on March 21, more than six weeks sooner than its previous earliest date, in 1947. The daily average of 73.1 degrees Las Vegas recorded in March would have broken the city's April record.

Overall, there's been less snowpack and higher temperatures than pretty much any winter on record. It's a situation that climatologists have said would be virtually impossible without climate change, and the maps reflect that reality.

"It doesn't mean that all of these areas are going to burn," said Alastair Hayden, professor at Cornell University and a former division chief in the California Governor’s Office of Emergency Services. Last year, for example, the Pacific Northwest saw an above-normal risk but was largely spared. Local patterns, such as wind and precipitation, play a major role, too. "But, when I look back at the forecast, fires usually tend to be in one of these locations."

The one notable spot on the latest maps that seems safe for now is Southern California, though that's because the fire season there doesn't usually start until later in the summer, or even into fall. There are also surprising splotches of red, like in Florida, which is experiencing a drought. But the West is by far the largest area of concern. "Keep an eye on July," said Hurteau. "The Fourth of July is the single highest ignition day of the year."

The sheer expanse of land that could be at risk simultaneously worries Hurteau. "Our fire suppression apparatus is in part dependent on the whole region not being on fire at the same time," he said. Fire crews count on being able to hop from hot spot to hot spot. If there are too many at once, resources could run thin.

The number of acres across the country that have burned through March is already 231 percent of the 10-year average. A wet spring, however, could change everything. It recently rained in Albuquerque where Hurteau is based, and, if it continues, the fire risk could go down dramatically. That's what happened last year.

"I'm sure that's what all the fire people are hoping for too, because that would be nice," said Hurteau. "But hope is not a great strategy."

This story was originally published by Grist. Sign up for Grist’s weekly newsletter here.

Cars on the road today are 99% cleaner than they were in 1970. Air quality in the United States is much, much better as a result. In Los Angeles, where I live, lead levels in the air were 50 times higher in the 1970s than today, and the amount of lead in kids’ blood has plummeted.

What made that drop possible is arguably the most important environmental technology ever invented: the catalytic converter.

California has long had the authority under the federal Clean Air Act to set emissions standards for cars and trucks that are higher than the nation's, and its early use of that authority is a major reason why catalytic converters are now standard in vehicles and people are healthier across the country.

At a time when the Trump administration is attacking California's ability to cut air and climate pollution and revoking its Clean Air Act waivers, it's helpful to remember just how important the state's leadership has been in making the air Americans breathe so much healthier.

As I recount in my forthcoming book, "Smog and Sunshine: The Surprising Story of How Los Angeles Cleaned Up Its Air," California's role in the emergence of catalytic technology is often downplayed. The passage of the 1970 Clean Air Act is typically given the credit. That law deserves accolades for its key role. So does William Ruckelshaus, the first administrator of the U.S. Environmental Protection Agency.

But without California's willingness in the early 1970s to push automakers to meet tough standards, the technology would have developed more slowly and the air would have remained dirtier for many more years.

Birth of the catalytic converter

Eugene Houdry invented the first catalytic converter technology in the 1950s. Years earlier, he had developed the Houdry process for catalytic cracking, which makes converting crude oil into gasoline much easier. That invention in the mid-1930s helped spur the mass adoption of cars and trucks in the U.S.

Widespread car ownership altered American life, changing where people lived, worked and vacationed. But cars also brought terrible smog as their use skyrocketed. When Houdry realized his life's work was choking the air of Los Angeles, he decided to do something about it. By the late 1950s, Houdry had invented a rudimentary catalytic converter.

You might think that this invention, which Houdry said could make "the lung cancer curve dip," would lead carmakers to install the technology on their new vehicles.

But that is not what happened. Instead, auto manufacturers engaged in what the government described as a yearslong conspiracy to keep emissions-limiting technology off the market, ultimately leading to an antitrust legal settlement.

It wasn't until the passage of the 1970 Clean Air Act that carmakers got serious about improving upon Houdry's invention for mass market installation.

The Clean Air Act's ambition

The 1970 Clean Air Act is a remarkable piece of legislation. Passed with only one negative vote and signed into law by President Richard Nixon, the act set wildly ambitious goals. They included a requirement that carmakers cut auto pollutants by 90% by 1975.

Congress passed this requirement knowing that the technology to cut emissions wasn't ready for prime time. Houdry's catalytic invention couldn't work with leaded gasoline, and it hadn't been tested in tough conditions, such as freezing cold or sweltering heat.

The Ford Motor Co., with Lee Iacocca as its president, told Congress in 1970, "If such (pollution cuts) are established … the technology as we know it today would not permit us to continue to produce cars after January 1, 1975."

Congress ignored Ford's dire warning and passed the stringent cuts.

Automakers responded with two separate tactics. The first was to gear up — alongside companies like Corning Glass and the Engelhard Company — to develop technology to meet the 90% cuts. Most of their efforts focused on improving the catalytic converter, made more plausible when Engelhard determined that catalytic converters wouldn’t corrode with unleaded gasoline. The EPA's Ruckelshaus ordered gas stations to make unleaded gasoline available as of Jan. 1, 1975.

While the auto companies worked to meet the congressional mandate, they also pressured Congress and the courts to weaken or delay it. The U.S. Court of Appeals for the District of Columbia Circuit obliged, ordering Ruckelshaus to extend the deadline for compliance by a year. Congress eventually extended the deadline to 1981.

But California did not let up.

A gamble that paid off

California has the authority under federal law to issue its own automobile pollution standards, as long as the standards are stronger than federal standards and the state receives a waiver from the EPA. No other state has similar power, but states can adopt California's higher standards.

After the federal appeals court gave carmakers an extra year to comply with the federal rules, California decided it would not let car companies off the hook.

The state asked Ruckelshaus to grant a waiver for California to issue standards tough enough that carmakers would have to install catalytic technology to meet them.

Ruckelshaus faced enormous pressure to deny the waiver, with automakers arguing that the technology was neither effective nor available. But in a hint of the resolve he would later show in refusing Nixon's order to fire Watergate special prosecutor Archibald Cox, Ruckelshaus gave California the go-ahead in 1973, and the state's rules went into effect for the 1975 model year.

He reasoned that doing so would maintain "continued momentum toward installation of (catalyst) systems … while minimizing risks incident to national introduction of a new technology." In other words, California could serve as a guinea pig for the rest of the country by adopting tough standards.

The gamble paid off. Since California was the nation's largest auto market, companies had strong economic incentives to change their models to meet the state’s standards. Catalytic technology is now not only standard on American vehicles but also on vehicles around the world, and air quality in the U.S. is vastly improved.

With the adoption of the catalytic converter, leaded gasoline was banned and eventually phased out, and lead levels began to drop almost immediately.

Continuing California's legacy

Catalytic converters have removed 8 billion tons of pollution from the air in the U.S. They have saved hundreds of thousands of lives and led to the removal of a deadly neurotoxin, lead, from the atmosphere.

California's standards have spurred important technological innovations for vehicles, including new types of less-polluting gasoline and vehicles that emit no pollution at all.

But the state's ability to set higher standards is under attack. Congress — at the behest of the Trump administration — has overturned three waivers the state was granted to cut even more pollutants and the greenhouse gases that cause climate change. The Trump administration has also sued California to invalidate its mandates for automakers to sell zero-emissions vehicles.

Today, California officials are searching for alternative ways to continue to make cars and trucks cleaner. The state has set aside money to replace federal tax incentives for electric vehicles, and the Legislature is exploring creative ways to hold indirect sources of emissions, such as rail yards, ports and warehouses where vehicles are constantly running, accountable for air pollution.

But these alternatives aren't as powerful as the authority to exceed federal standards to make the air cleaner.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

A warming climate could expose a Pennsylvania-sized chunk of ice-free land in Antarctica by 2300, which could drastically reshape Antarctic geopolitics as well as the continent's geography.

A study published in Nature Climate Change is the first to incorporate glacial isostatic adjustment — how land beneath heavy ice sheets uplifts after the ice retreats — into projections of ice-free land emergence in Antarctica. The results reveal that climate change could expose potentially valuable mineral resources that may spur renegotiations of the international treaties that currently govern Antarctica.

As more ice-free land emerges in Antarctica, said Erica Lucas, a geophysicist at the University of California, Santa Cruz, countries may become more interested in its mineral resource potential. Lucas is the lead author of the new study.

Rebounding resources

Beneath Antarctica's ice sheet lies a varied landscape with mountains, canyons, valleys, and even volcanoes. As the climate warms, the ice sheet is slowly retreating, uncovering some of that land.

But until now, projections of ice-free land emergence had considered only changes to ice margins — how the spatial extent of ice cover will shift. Simulations of Antarctica's future accessible land hadn't considered how land would uplift once uncovered by ice or how different sea level scenarios would affect the amount of ice-free land that might emerge.

Lucas's projections included these factors by incorporating expected sea level changes, information about the thickness of Earth's lithosphere, and estimates of how the absence of the gravitational pull of an ice sheet would affect land uplift.

The study estimated that 120,610 square kilometers (46,578 square miles), 36,381 square kilometers (14,047 square miles), and 149 square kilometers (58 square miles) of land would emerge by 2300 under high–, medium–, and low–ice melt conditions, respectively. "We know we’ve had ice retreat and grounding line retreat over the past couple of decades," so the ranges of projected ice-free land emergence were not surprising, Lucas said.

South pole politics

Within the area that Lucas and the research team projected would be ice-free by 2300 lie known or suspected deposits of copper, gold, silver, iron, and platinum — critical minerals used in manufacturing and valuable metals in and of themselves. In particular, the study found the largest land emergence in Antarctica is likely to occur over territories claimed by Argentina, Chile, and the United Kingdom and contains a range of mineral deposits, including copper, gold, silver, and iron.

Currently, commercial mineral extraction is not allowed in Antarctica, though the Antarctic Treaty does allow for activities related to mineral resources if they are conducted strictly for scientific purposes.

If mineral resources become simpler to extract, countries with territorial claims in Antarctica would have an incentive to renegotiate those terms, the study's authors suggest. The first window for renegotiation is in 2048, when parties to the Antarctic Treaty are permitted to call for a review of the treaty's environmental protocol.

The authors suggest that these changes to Antarctic land could put pressure on the region's legal framework surrounding mineral resource activities. "That's a fair assessment," wrote Tim Stephens, a professor of international law at the University of Sydney Law School who was not involved in the new study, in an email. "However, the ice-free land emergence projected by the new study is unlikely to trigger a major change to Antarctic governance on its own," he wrote.

"The continent will still remain a very challenging environment for mineral resource extraction," he wrote, adding that the transformation of the Antarctic environment could also spur greater cooperation and focus on the environmental protection objectives of the Antarctic Treaty.

This article was originally published on Eos.org. Read the original article.

The world's best climate models are not capturing the true extent of Earth's energy imbalance, and scientists aren't sure why.

Instead of mirroring real-life satellite observations, the models consistently underestimate a growing gap, or imbalance, between the amount of energy Earth receives from the sun and the amount the planet radiates into space, a new study shows. It's unclear what missing component would bring the models up to speed, but researchers think it could be related to how clouds interact with small particles in the atmosphere known as aerosols.

"The representation of cloud changes in response to aerosol changes may not fully reflect reality," study lead author Seiji Yukimoto, a climate scientist in Japan's Meteorological Research Institute, told Live Science in an email.

Satellite observations show that Earth's energy imbalance has more than doubled over the past two decades and risen especially fast since 2010. More energy is being trapped in the atmosphere than is expelled into space, driving up temperatures, according to the study. Human emissions of greenhouse gases are to blame for most of the energy imbalance, but scientists say there are other factors at play.

In 2023, the imbalance reached 1.8 watts per square meter (0.16 watts per square foot), which was twice what climate models estimated based on rising greenhouse gas emissions. Models in general show an increase in Earth's energy imbalance, but the rate differs between simulations, and they never mirror exactly what satellite observations show, Tianle Yuan, an atmospheric scientist at the University of Maryland, Baltimore County and NASA's Goddard Space Flight Center, told Live Science in an email.

Researchers have tried to explain this discrepancy by proposing that the simulations may not fully account for feedback processes, natural variability and declines in aerosol emissions. To find answers, Yukimoto and his colleagues reconstructed Earth's energy imbalance between 2001 and 2024, using 15 state-of-the-art climate models, satellite radiation data and surface temperature records.

The results, published Feb. 22 in the journal Geophysical Research Letters, confirm that some processes in the climate system are missing from the models. The simulations underestimated the amount of energy that Earth absorbed from the sun, particularly between 2010 and 2024, when satellite data shows that Earth's energy budget was completely out of whack.

"Their analysis is solid and straightforward," said Yuan, who was not involved in the study. "They analyzed different emission scenarios and none can fully simulate the observations. They find a failure of models to capture the strong increase in [Earth's energy imbalance]."

This failure suggests that the models are missing hidden mechanisms that are reducing the amount of energy Earth radiates into space. Climate models account for greenhouse gases, but they may not capture the effect that rising surface temperatures have on clouds and other elements that regulate how much energy escapes into space, according to the study. There is also a question regarding the influence of aerosols, which have declined since 2010 due to cuts in China's emissions and new shipping regulations.

High aerosol concentrations lead to more abundant and smaller cloud droplets, which reflect more light and energy into space. Aerosols also affect the lifespan of clouds, Yukimoto said. Thus, falling aerosol concentrations in the atmosphere may influence how clouds scatter light and energy.

"Aerosols are heterogeneous in type and distribution, and their effects vary depending on the location and conditions of the affected clouds, making them extremely difficult to [model]," Yukimoto said.

If the sharp increase in Earth's energy imbalance since 2010 is due to cuts in aerosol emissions, the rate of increase should decline as aerosol levels stabilize, Yukimoto said. If, instead, the increase is from clouds reacting to rising surface temperatures, Earth's energy imbalance could grow bigger and warm the planet faster than greenhouse gases alone could. But "our results contradict this," Yukimoto said.

The gap between observations and models is widening. To get more realistic results, scientists could get the models to more accurately represent the impact of sea surface temperatures and aerosols on clouds, Yukimoto said.

Cloud-aerosol interactions may be the key to fixing the models, and several studies support this idea — but uncertainties remain, Yuan said. "It would be nice to get more details such as how subsets of models perform differently and dive into the possible causes of this underestimation by models," he said.

Dangerous weather events typically associated with extreme global warming could become more frequent even under moderate levels of heating, a new study finds.

Deadly floods in cities and catastrophic droughts in major crop-producing regions may hit more often than previously thought under a climate scenario where global temperatures stabilize at around 3.6 degrees Fahrenheit (2 degrees Celsius) above preindustrial levels, researchers found. The same goes for forest wildfires, which could be more frequent and devastating under a 3.6 F scenario than scientists previously understood.

"Our results do not mean that 2 C of global warming would be as severe overall as much greater warming," study lead author Emanuele Bevacqua, head of the Climate Compound Extremes group at the Helmholtz Center for Environmental Research in Germany, told Live Science in an email. "Rather, they show that extreme impacts in particularly vulnerable or socially important sectors may occur even under moderate warming of 2 C."

The researchers used the same ensemble of 50 climate models as the Intergovernmental Panel on Climate Change (IPCC) did in its latest assessment report. However, unlike the IPCC and many climate studies that draw conclusions from averages calculated across all 50 models, Bevacqua and his colleagues explored the models separately to identify a range of possible outcomes under a 3.6 F warming scenario.

The team focused on three sectors that are particularly vulnerable to specific climate impacts: highly populated areas, which are extremely susceptible to rainfall and flooding; breadbaskets, which are more sensitive to drought; and forests, which are especially at risk from wildfires. For each sector, the researchers ranked their model results from lowest impact to highest impact. Then, they compared this ranking to climate outcomes that were obtained by averaging the results of the 50 models under 5.4 F (3 C) and 7.2 F (4 C) of warming.

The study results, published March 25 in the journal Nature, indicate that 3.6 F of warming, which is considered a moderate scenario, can trigger climate events in each studied sector that vary hugely in intensity depending on the model. This means that even under moderate warming, there is great uncertainty and a wide range of possible climate outcomes, some of which are as extreme or more extreme than what researchers had expected for warming of 5.4 F or 7.2 F above preindustrial levels.

In highly populated areas, precipitation could increase by 4% to 15% under 3.6 F of warming relative to preindustrial conditions, the researchers found. High rainfall in cities can cause disastrous floods because drainage capacity is limited, according to the study. The worst-case scenarios were more extreme than what is typically expected under 5.4 F of warming, particularly in India and west central Africa.

Droughts in major crop-growing regions produced the most uncertainty across models, with some showing limited impacts and others — roughly 1 in 4 — indicating that droughts under 3.6 F of warming could be as severe or more severe than is typically expected under 7.2 F of warming. The worst-affected regions were the Indian subcontinent, East Asia, southeast South America, southeast Australia, the Caucasus and central North America.

In forested regions, there is a roughly 1-in-5 chance that fire-causing weather could become as intense or more intense under 3.6 F of warming than what is typically expected from models with 5.4 F of warming, the researchers found. The worst-impacted regions in the grimmest projections were Canada, central Africa, northeast South America, northeastern Europe and parts of Russia. Forests in these regions are critical carbon sinks that have already suffered significant losses in the past two decades, the researchers noted in the study.

There is a low chance that the most extreme outcomes in the study will occur under 3.6 F of warming, but researchers should examine them in case they do, because this would have huge consequences and require advance adaptation planning, Bevacqua said.

"Focusing on the most likely outcome or model averages alone can create a false sense of security about moderate global warming," he said. "At the same time, the plausibility of extreme outcomes should be carefully evaluated. As global warming approaches 1.5 C [2.7 F], these findings reinforce the urgency of limiting warming well below 2 C."

Christian Franzke, a professor in the Center for Climate Physics at Pusan National University in South Korea who was not involved in the study, agreed that the results highlight the need to limit warming as fast and as drastically as possible.

What's new in this study is that the authors demonstrated a wide range of best-to-worst impacts with one warming scenario, Franzke told Live Science in an email. "I am not surprised by the results," he said. "But you have to keep in mind that they compare extremes at 2 C global warming with the mean states at 3 C and 4 C."

In crop-producing regions, we could mitigate real-life climate outcomes under 3.6 F of warming with better water policies, Franzke said. But climate models could also be missing something. "In the real world we can face unanticipated bad surprises," he said.

China's significant reduction in air pollution may have had unexpected benefits in the Arctic: A new study shows that it diminished storms fueled by aerosols and, in turn, reduced sea ice loss. However, at the same time, this huge drop in aerosols may have accelerated global warming, experts say.

"The Chinese people suffered under bad air quality for decades," Bjørn Samset, a senior researcher at the CICERO Centre for International Climate Research in Norway, told Live Science. "This pollution temporarily slowed global warming and gave the rest of us a bit more time to adapt to a warmer climate. What is happening now is that we're seeing the full effects of greenhouse-gas-driven warming, which we would sooner or later have to face anyway."

In late January 2019, wind patterns over the North Pacific shifted, and a series of five powerful cyclones swept into the Bering Sea in rapid succession. Each one drove warm southerly winds across the ice, breaking it apart and pushing it northward. Air temperatures across the northern Bering Sea ran 21.6 to 28.8 degrees Fahrenheit (12 to 16 degrees Celsius) above normal. By early March, ice cover had shrunk by 82%. This represented a retreat of about 154,440 square miles (400,000 square kilometers) — the largest decline ever recorded by satellites at that time of the year.

Scientists have long known that cyclones can devastate Arctic sea ice. What they've been less sure about is what sends those storms there in the first place.

The new study, published March 18 in journal npj Climate and Atmospheric Science, offers an unexpected answer: From 2000 to 2014, smog billowing from Chinese smokestacks may have been steering winter storms northward across the North Pacific, funneling more of them into the Arctic and destroying ice in the Bering Sea.

To understand how soot and sulfate particles over Shanghai could influence ice off the coast of Alaska, it helps to think about what happens inside a storm. Every mid-latitude cyclone — the swirling, comma-shaped systems that generate much of the Northern Hemisphere's winter weather — runs on a kind of heat engine. Warm, moist air evaporates near the ocean surface, rises and condenses into clouds, releasing heat that fuels the storm's circulation.

Aerosols — the tiny particles that make up industrial haze — disrupt this engine in a subtle-but-consequential way. Water vapor normally condenses around a relatively small number of particles, forming large droplets that fall quickly as rain on the storm's southern flank. If the air is full of aerosols, however, each particle becomes a seed for a cloud droplet. The result is a vast number of smaller droplets that don't readily coalesce into raindrops. Rainfall on the storm’s southern flank is suppressed, and moisture travels farther along the storm's conveyor belt toward its northeastern flank, where it releases its heat — in exactly the right place to nudge the whole system poleward.

Lead author Dianbin Cao, a researcher at the Chinese Academy of Sciences' Institute of Tibetan Plateau Research, and colleagues combined four decades of observational data with climate model simulations to examine how aerosol levels over East Asia influenced winter cyclone tracks across the North Pacific. Comparing 14 years of elevated aerosol loading between 2000 and 2014 against 15 lower-aerosol years from the preceding decades, the researchers found that cyclone tracks shifted northward by up to 1.23 degrees by the time the storms dissipated — enough to nearly double the number of cyclones crossing into the Arctic.

This aerosol-driven push on storm systems is "stronger than I might have suspected," said Alex Crawford, an Arctic climate scientist at the University of Manitoba who studies cyclone-sea ice interactions but was not involved in the study. "They've done a really good job of demonstrating the mechanism by which aerosols can impact extratropical cyclones."

When these storms arrive in the Bering Sea, their effects can be dramatic. A cyclone's counterclockwise winds shove ice back toward the Chukchi Sea, between Alaska and Russia. Waves break ice floes apart. Southerly gales bring warmer air that can, even in the depths of winter, tip temperatures above freezing, as happened so acutely in 2019.

There is a potential silver lining, however. China's air pollution cleanup, launched in 2013, has proved to be one of the most effective environmental interventions in history, slashing the country's sulfate aerosol emissions by roughly 75% in about a decade. The study suggests this reduction "could potentially mitigate the poleward migration of the storm track driven by global warming" — sparing the Arctic some of the damage from extratropical cyclones.

But the bigger picture is more complicated. Aerosols also cool the planet by reflecting solar radiation back into space and by making clouds brighter. As they disappear, their cooling effects vanish too, thereby unmasking decades of suppressed greenhouse gas warming. A 2025 study led by Samset, who was not involved in the new study, found that East Asian aerosol reductions have measurably accelerated global warming.

The same aerosol reductions that may ease the cyclone-driven pressure on the Bering Sea are simultaneously unmasking the full effects of global warming.

What this climatic tug-of-war will mean for Arctic sea ice remains to be seen, but Dan Westervelt, an atmospheric scientist at Columbia University’s Lamont-Doherty Earth Observatory and a co-author on Samset’s 2025 study, thinks the warming effect will win out. "Unmasking warming will probably dominate, as it is more persistent and can occur during all seasons, while the storm-track changes are probably more episodic,” he told Live Science.

Westervelt said the study indicates that aerosols exert a greater and more complicated influence on Earth's climate than previously appreciated. "The speed of the aerosol reductions in East Asia is underappreciated," he said. "Emissions decreases that took three decades in North America and Europe are taking one decade in East Asia. What impact this has on cyclones and Arctic warming is going to be really interesting to study, and critical for climate mitigation and adaptation."

A study of soil microbes showed that drought favors the microorganisms that survive antibiotics. It also found that some of the genes for resistance in soil-dwelling bacteria show up in antibiotic-resistant pathogen samples collected from hospital patients. Because bacteria can easily swap big chunks of genetic information ‪—‬ a process called horizontal gene transfer ‪—‬ any increase in resistance in soil-inhabiting microbes can easily make its way to microbes that infect humans, the study authors said.

"No place is immune," said Dianne Newman, the study's senior author and a biologist at Caltech. "If you have a pathogen arise in one part of the world, it very quickly spreads, so this is something of concern regardless of where you live."

Resistant pathogens

Antibiotic resistance is already a major health problem, with the World Health Organization estimating that antibiotic-resistant pathogens directly caused 1.27 million deaths per year as of 2019 and contributed to another 4.95 million. While antibiotics kill microbes, the drugs people use in the clinic are also derived from microbes (or fungi, such as in the famous case of penicillin). Microbes synthesize antibiotics as part of an evolutionary arms with other microbes, aiming to kill any potential competitors or threats. One of the major battlegrounds for this evolutionary warfare is in soil.

Newman and the new study's first author, Caltech postdoctoral researcher Xiaoyu Shan, first uncovered a hint that drought could worsen antibiotic resistance in a set of five metagenomics databases that gather soil microbe genetic information from different environments on continents around the world. Some of these databases included samples from the same sites before and after drought.

In every case, the researchers found, antibiotic synthesis genes were more prevalent after a dry period and less prevalent after a drought ended.

"You see this in croplands, in grasslands, in forests, in wetlands, in the U.S., in China, in Switzerland," Newman told Live Science.

To find out what was going on, Newman, Shan and their colleagues took the question to the lab. They treated sterile soil with the antibiotic phenazine, which is produced by some species of bacteria. Then, they added soil-dwelling bacteria and allowed half of the samples to dry out for three days, while keeping the rest moist.

After this simulated drought, they discovered that the antibiotic in the soil had, unsurprisingly, become more concentrated as the moisture in the soil evaporated. They also found that, in response to this more concentrated antibiotic, bacteria in the soil that were sensitive to antibiotics suffered, while antibiotic-resistant bacteria flourished.

These findings illustrate that antibiotic resistance is driven by evolutionary pressure, Newman said. Only the toughest, most resistant survive when drought concentrates other microbes' antibiotics to lethal levels.

To get a glimpse of this evolutionary battlefield on a genetic level, the researchers returned to the large metagenomics databases. They found that genes for antibiotic resistance became more common in dry periods. This prevalence went hand in hand with the increase in genes for antibiotic synthesis, supporting the idea that drought-stricken microbes boost their antibiotic resistance in response to increased pressure from antibiotic assaults from their neighbors.

Next, the researchers took soil samples from the Caltech campus, added four different antibiotics, and dried out half of the samples. Again, they saw more antibiotic-resistant microbes in the desiccated samples.

A global peril

The next question was whether these patterns could be seen on a global scale. The researchers used existing data on antibiotic-resistant pathogens collected at hospitals around the world, as well as climate and weather data, to quantify the aridity at each hospital. They found that the dryer the region, the more antibiotic-resistant pathogens the hospital reported. The finding held even when the researchers controlled for a country's socioeconomic status, which might influence pathogen testing.

A final genomic scavenger hunt provided one more piece of bad news: Many of the genes that confer antibiotic resistance in soil microbes were found, replicated exactly, in clinical pathogens known to escape antibiotics. These included the common hospital pathogens Enterococcus faecium, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and species of Enterobacteria, the researchers reported March 23 in the journal Nature Microbiology. Human pathogens and soil microbes come into contact all the time as people move around the environment, Newman said, and drought-induced resistance can easily transfer from microbes in soil to microbes on the body.

"Continued warming and drying is expected to expand arid conditions," Timothy Ghaly, a microbial ecologist at Macquarie University in Australia, wrote in an editorial accompanying the study. That means climate change could accelerate the already-serious problem of antibiotic-resistant pathogens, he wrote.

There are ways to wage our own evolutionary battle against the bacteria, Newman said. Beyond limiting climate change, more could be done to get rapid diagnostic tests into clinics so doctors can treat antibiotic-resistant bacteria faster. They can also choose multi-antibiotic treatments that knock out resistant strains. Another crucial step, Newman said, is to fund basic research in drug discovery. Pharmaceutical companies have largely pulled back from seeking out new antibiotics because of lack of profitability, which leaves government and academic scientists at the vanguard of basic research.

"This is not the time for governments to stop funding scientific research and drug discovery," Newman said.

The first two weeks of the war between the U.S., Israel and Iran created immense present and future greenhouse gas emissions, draining the global carbon budget faster than 84 countries combined, a new analysis finds.

Between Feb. 28 and March 14, 2026, the warring parties released almost 5.6 million tons (5.1 million metric tons) of carbon dioxide (CO₂) and other greenhouse gases by firing carbon-intensive weapons, powering fighter jets and ships, and bombing infrastructure such as oil storage facilities and civilian buildings, researchers found.

For comparison, if these emissions continued at the same rate for one year, they would be roughly equivalent to the annual carbon emissions of the 84 lowest emitting countries in the world combined. And the emissions from the first two weeks of the conflict are higher than Iceland's annual carbon emissions, which in 2024 totaled 4.7 million tons (4.3 million metric tons) of CO₂ via all sources, the team said.

"Every missile strike is another downpayment on a hotter, more unstable planet, and none of it makes anyone safer," Patrick Bigger, a co-author of the analysis and a research director at the Climate and Community Institute, a climate and economy think tank, told The Guardian.

The analysis and an accompanying opinion article written by the researchers were published March 21 by the Climate and Community Institute.

The biggest source of CO₂ from the conflict in Iran during its first two weeks was the destruction of homes, schools and other buildings, as the rubble will need to be cleared and the infrastructure must be rebuilt after the war ends, according to the analysis. Bigger and his colleagues calculated that these indirect emissions amount to about 2.7 million tons (2.4 million metric tons) of CO₂, which is equivalent to the Maldives' yearly emissions. Based on data from Red Crescent Society of Iran, a humanitarian organization, the infrastructure that has been razed includes 16,191 residential buildings, 3,384 commercial units, 77 medical centers and 69 schools, the researchers noted in the study.

The second largest chunk of CO₂ emissions from the first 14 days of the war came from the U.S., Israel and Iran's bombarding of oil storage facilities, oil refineries and oil tankers across the Gulf region. The researchers found that 2.5 million to 5.9 million barrels of oil were blown up during their analysis period, unleashing 2.1 million tons (1.9 million metric tons) of CO₂ and other greenhouse gases into the atmosphere — roughly equivalent to Malta's annual emissions.

Fuel used during combat and support operations in the first two weeks of the war was the third-biggest source of CO₂, totaling about 583,000 tons (529,000 metric tons) of the greenhouse gas, which is comparable to Greenland's yearly emissions. The U.S. and Israel struck more than 6,000 targets in Iran using fighter jets and bombers between Feb. 28 and March 14, according to the analysis. This is equivalent to about 2,500 flights lasting three hours each, which, together with the transport of troops and other support activities, likely consumed 150 million to 270 million liters (40 million to 71 million gallons) of fuel, the researchers estimated.

In the first two weeks of the war, the U.S. lost three F-15 fighter jets and one KC-135 refueling aircraft. In the same period, Iran is reported to have lost 28 planes, 21 ships and about 300 missile launchers. This equipment will likely be replaced through manufacturing, and this makes up the fourth-largest source of CO₂ in the analysis, totaling 190,000 tons (172,000 metric tons) of the greenhouse gas. That's about the same as Tonga's annual emissions.

Finally, the researchers estimated that the U.S. and Israel launched 9,000 missiles in the first 14 days of the war. Iran, meanwhile, is thought to have launched 1,000 missiles and about 2,000 drones in the same period. Similar to planes, ships and missile launchers, the warring parties will likely replenish this arsenal, which also includes interceptor missiles. According to the analysis, the embodied CO₂ emissions amount to roughly 61,000 tons (55,000 metric tons), which is equivalent to a small cement plant's yearly emissions.

The war is in its fourth week, meaning that far more CO₂ has now been emitted directly and indirectly as a result of the conflict than the analysis suggests.

"We expect emissions to increase rapidly as the conflict proceeds, mainly due to the speed [at] which oil facilities are being targeted at an alarming rate," Fred Otu-Larbi, a co-author of the analysis and a researcher at Lancaster University in the U.K. and the University of Energy and Natural Resources in Ghana, told The Guardian. "Just what are the costs, no one really knows, that is why studies like this are so vital."

If more countries join the war, they could significantly boost emissions, the researchers wrote in the analysis. But already, "burning up the annual emissions of Iceland in two weeks is something we really cannot afford," Otu-Larbi said.

The aftershocks of the war are expected to have an even bigger climate impact than the fighting itself, as countries seek to buffer against fuel and fertilizer shocks caused by Iran's blockade of the Strait of Hormuz. Specifically, there could be an increase in drilling for fossil fuels as countries seek to become as energy secure as possible, the researchers said.

"Historically, every U.S.-driven energy shock has been followed by a surge in new drilling, new LNG [liquified natural gas] terminals and new fossil-fuel infrastructure," Bigger said. "This war risks hard-wiring another generation of carbon dependence."

Antarctica could heat up 1.4 times faster than the rest of the Southern Hemisphere over the coming decades, which would lock in extreme sea-level rise and ravage polar ecosystems, a new modeling study shows.

This acceleration of warming in Antarctica relative to other regions, known as Antarctic amplification, would likely occur if global temperatures reached 3.6 degrees Fahrenheit (2 degrees Celsius) above preindustrial levels, according to the study. The world has already warmed by 2 F (1.1 C), and the pace at which new temperature records are being set is intensifying. If emissions stay around current levels, we will likely reach 3.6 F of warming around 2050 — but if emissions keep rising, we could hit that threshold around 2040.

The new research is among the first to find a clear sign of Antarctic amplification, which has been hard to detect due to the Southern Ocean's enormous capacity to absorb heat and the powerful circumpolar currents that isolate the frozen continent from rising temperatures. Yet most scientists think Antarctic amplification will happen, because amplification in the Arctic is already underway.

"For many years, Antarctica seemed isolated from the effects of increasing global temperatures," Ariaan Purich, a senior lecturer and climatologist at Monash University in Australia who was not involved in the research, told Live Science in an email. "In this new study, the authors propose that long-term surface warming of the ocean around Antarctica, projected by climate models over the coming century, leads to Antarctic amplification."

Arctic amplification has been documented for years, with temperatures in this region climbing about four times faster than the global average increase over the past five decades. The main mechanism driving Arctic amplification is the ice-albedo feedback, where the melting of snow and ice accelerates warming because water reflects less heat back to space. Where there once used to be reflective sea ice, there is now an ocean that absorbs more heat from sunlight. This causes more ice and snow to melt, in turn exposing even more heat-absorbing water.

Antarctica behaves differently, partly because swirling ocean and wind currents shield the continent from rising air and sea temperatures elsewhere in the world. Contrary to the Arctic, most of Antarctica experienced only gradual warming and no declines in sea ice until about a decade ago, Purich said.

But then, between 2014 and 2016, Antarctica lost as much sea ice as the Arctic had lost in four decades. The continent hasn't bounced back since, Purich said, with exceptionally low winter sea ice extent recorded in 2023, in particular.

"We're now seeing abrupt changes occurring in Antarctica, at very rapid rates," Purich said. "With low Antarctic sea ice coverage, there is now the potential for the ice-albedo feedback to start exacerbating warming of the southern high latitudes."

But scientists haven't observed this amplification signal directly yet. So, for the new study, researchers in China analyzed data from climate models to investigate whether Antarctic amplification could occur under a 3.6 F warming scenario. Using polar amplification simulations, along with models developed for the latest Intergovernmental Panel on Climate Change (IPCC) report, the researchers explored the impact of continued global warming on Antarctic temperatures.

Their findings — published Dec. 22, 2025, in the journal Geophysical Research Letters — suggest Antarctica will warm faster than the Southern Hemisphere as a whole under future climate conditions.

The researchers also discovered the main driver of Antarctic amplification: Unlike in the Arctic, where the ice-albedo feedback is a key driving force, Antarctica will warm mainly through accelerating heat release from the surrounding ocean.

Antarctic amplification may not have set in yet, but the effects of climate change have already arrived, Purich said. Over the past decade, scientists have observed drastic declines in Antarctic sea ice and catastrophic breeding failures in emperor penguins (Aptenodytes forsteri) due to melting.

"These things are happening now, and every fraction of warming that we can avoid matters," Purich said.

The new study is based on models, which, in the case of Antarctica, means the results may underplay future amplification, Purich said. Climate models are limited in their ability to predict certain warming mechanisms, and it's still unclear exactly how Antarctica's circumpolar currents will affect temperature changes.

"Together, this raises the possibility that the climate models may underestimate the potential and magnitude of Antarctic amplification to emerge over coming decades and centuries," Purich said.

Antarctica quiz: Test your knowledge on Earth's frozen continent

Today's top story

Earth's climate imbalance breaks record

The world's climate is more out of balance than at any time in recorded history, the UN's weather agency said in a dire warning today.

We already know that human-released carbon emissions blanket Earth's atmosphere and increasingly trap more solar radiation than can be reemitted back into space, creating an imbalance that heats the planet. But a new report by the World Meteorological Organization (WMO) has revealed that this process is happening faster than any time in history, with 2025 beating the previous record set the year before.

Much of the excess heat, roughly 91%, was absorbed by the oceans; another 5% heated the land; 3% went into ice and 1% into the air. The spillover effects of this planetary heating are also becoming more pronounced. This month alone there has been snow in Alabama, a record-shattering heatwave across the West, and flooding that has prompted evacuations in Hawaii.

The trend

Round 2 for Artemis II

NASA's Artemis II moon rocket is back on its launchpad as the space agency makes a final bid to launch the spacecraft before its April deadline.

This is the second time that the 322-foot-tall (98 meters) Space Launch System and Orion capsule stack has rolled out to the launchpad this year, the first having taken place on Jan. 17. But following two wet dress rehearsals and two leaks, NASA decided to wheel the rocket back to the Vehicle Assembly Building for repairs.

NASA is expected to announce further tests this week. If the fixes have worked as planned, the rocket could blast off as early as April 1.

Three to read

1. A new twist on matter? Strange 'Half-Mӧbius' molecule has rare properties chemists have never seen before [Live Science]
2. China could be the world’s biggest public funder of science within two years [Nature]
3. 5m tonnes of CO2 emitted in just 14 days of US war on Iran, analysis finds [The Guardian]

Say it, said it

Word of the day

Stereopsis — Greek for "solid sight", used to describe the forward-facing eyes of predators including cats, snakes and humans that judge distance by comparing the slight differences between their two views.

Quote of the day

"Our ability to adapt to our different environments and the cultural adaptations we see, the biological — that's our superpower. That's why there's 9 billion of us and not 9 billion of some other primate."

Herman Pontzer, a professor of evolutionary anthropology and global health at Duke University, on how humans used adaptability to take over the planet.

Fun and games

You're reading this on one kind of computer or another. But how much do you know about the history of the now-ubiquitous technology? Test your knowledge with this quiz.

Follow Live Science on social media

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Human-driven climate change is slowing Earth's rotation at a rate not seen in 3.6 million years, with sea level rise increasing the length of days by 1.33 milliseconds per century, according to a new study.

Earth spins faster when its mass is more concentrated, just as twirling figure skaters pull in their arms to speed up and spread out their arms to slow down. Rising sea levels have long been known to redistribute that mass and change the planet's spin, but the newly identified rate is unprecedented, scientists say.

Many factors influence Earth's spin speed. The moon's pull on the planet is the most significant over the long term. Its gravitational pull creates a bulge in the planet that slows Earth's rotation rate, Michael Mann, a climatologist at the University of Pennsylvania who was not involved with the new study, told Live Science. The moon's influence increases Earth's day length by about 2.4 milliseconds per century.

However, this 2.4 millisecond rate is offset by an effect called glacial isostatic adjustment, which is the slow rise of the planet's crust that continues to occur after the retreat of the ice sheets. Glacial isostatic adjustment shortens the day length by about 0.8 millisecond per century, leading to a background lengthening over time of 1.71 milliseconds per century (with about 0.1 millisecond of uncertainty in the observations).

Other, shorter-term phenomena also affect day length, including strengthened winds during El Niño events, which slow the planet's rotation by about a millisecond per century, Mann said.

However, in recent years, the climate seems to be playing an increasing role in altering Earth's rotation, said study co-author Mostafa Kiani Shahvandi, a geoscientist at ETH Zurich. "I wanted to know if this was unusual or something like this happened in the past," Shahvandi told Live Science. "As it turned out, it is quite anomalous. The effect is therefore anthropogenic [caused by humans]."

Shahvandi and study co-author Benedikt Soja, a professor of space geodesy at ETH Zurich, turned to the fossils of shelled single-cell organisms called foraminifera to peer back millions of years into Earth's day length. Changes in the oxygen content of these fossils could reveal sea levels when the organisms were alive, from which the researchers could extrapolate day lengths.

They found that today's 1.33-millisecond-per-century increase in day length was among the fastest changes seen in the past 3.6 billion years. "This is expected to get even larger and even bigger than the effect of the moon," Shahvandi said.

One episode around 2 million years ago saw a similar increase in day length of 2.1 milliseconds per century , the researchers found. That was in the Early Pleistocene, during a period when carbon dioxide in the atmosphere and temperatures rose. There is some uncertainty in the historical estimate, meaning that this period may have seen a similar increase in day length as today, or that today might be faster.

Under a future warming scenario where greenhouse gases increase, the day could lengthen by 2.62 milliseconds per century by 2080, Shahvandi and Soja reported in their study, which was published March 10 in the journal JGR Solid Earth.

Although the impact would likely not be perceptible to humans, the findings have other real-world implications. For example, Mann said, instruments that require precise knowledge of Earth's rotation rate, such as those on spacecraft, may need to be recalibrated. Other precise timekeeping applications, such as in computing, could be affected, Shahvandi said.

The findings also underscore the rapidity of modern warming. "It tells us about the rapid climate change," Shahvandi said, "[the] melting of snow and ice in polar ice sheets and mountains glaciers, and increase in the sea levels."

Today's top story

The Americas settlement question remains unsettled

A key archaeological site in Chile could be thousands of years younger than first thought, according to a controversial study that threatens to rewrite the earliest history of when humans settled South America.

Monte Verde, a Paleolithic archaeological site in the mountains of southern Chile, stands as one of the oldest human settlements in the Americas and is believed to be 14,500 years old. Its discovery in 1976 fundamentally changed the way archaeologists see the arrival of the first Americans on the continent, as the site is 1,500 years older than the arrival of Clovis people through North America.

But a new study claims the site could be more than 10,000 years younger than first thought, completely upending the accepted understanding of the site and prehistoric migration patterns. But other experts have called the new paper "egregiously poor geological work."

The trend

Feeling the heat

A historic heatwave slamming the American West is on course to set monthly records in more than 140 cities, from California to the Plains, this week.

And it's far from an ordinary one — with the Arizona desert community of Martinez Lake reporting a high of 110 degrees Fahrenheit (43 degrees Celsius), smashing the record for the highest March temperature ever logged in the U.S.

Some scientists are arguing that the planet's increasingly wacky weather extremes are signs that human-driven climate change is accelerating. The debate is happening at the same time as the Iran war, which is already making American consumers reconsider their relationship with oil.

Three to read

1. Scientists witness birth of one of the universe's strongest magnets for the first time, thanks to a general relativity 'magic trick' [Live Science]
2. Carbon dioxide levels are higher than humans have ever experienced. It could be changing our blood chemistry [CNN]
3. Mathematician wins 2026 Abel prize for solving 60-year-old mystery [New Scientist]

Video of the day

Pong, with extra steps

Scientists in China have developed a system to teach humanoid robots movements skills based on fragmentary human data. And they've used it to train an android to play tennis.

While the robot is yet to be a match against professional players, it still returned a 96.5% return rate in its best performance, according to the yet-to-be-peer-reviewed study.

Say it, said it

Word of the day

Metis — Greek for "wisdom," and the name of Zeus' first wife and advisor, who helped him escape from his father Cronus' stomach and whom he repaid by swallowing after learning she will bear a son mightier than him.

Metis, already pregnant with Athena, the goddess of wisdom, helped her daughter escape from Zeus through his forehead. Athena's birth is depicted in the marble sculptures of the Acropolis, a fragment of which has been found near the remains of a shipwreck at the bottom of the Aegean Sea.

Quote of the day

"Thermodynamics tells you what's possible and what's not possible if the laws of the universe are what we think they are. Until now, there's nobody in four centuries of science that has been able to show that the laws of thermodynamics [do not apply]."

Angel Cuesta Ciscar, a professor of electrochemistry and physical chemistry at the University of Aberdeen in Scotland, on why it's unlikely that a "dark oxygen" discovery on the seafloor is even possible.

Fun and games

The archaeological community is once again locked into fierce debate over the timeline of the American continent's first settlement. But how much do you know about the first people to reach it? Test your knowledge with this quiz.

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Want more science news? Follow our Live Science WhatsApp Channel for the latest discoveries as they happen. It's the best way to get our expert reporting on the go, but if you don't use WhatsApp we're also on Facebook, X (formerly Twitter), Flipboard, Instagram, TikTok, YouTube, Bluesky and LinkedIn.

Thirsty plants are sucking up water that would otherwise end up in the Colorado River, according to a new study. The findings could have important implications for water management in regions that rely heavily on snowmelt for their water, including Arizona and California.

More than 1.4 billion people around the world rely on water from snowmelt-driven mountain rivers. In the United States, more than 10% of the population gets the majority of their water from the Colorado River alone.

But as global temperatures rise, less water is flowing into the Colorado River and many other rivers, and an understanding of what is driving that change is essential to managing water in a hotter and drier future.

Most water in mountain ecosystems is lost through a combination of evaporation from the soil and a process called plant transpiration, in which plants release water vapor from their leaves. This combined process is known as evapotranspiration. Scientists had thought plants mostly drew on shallow soil moisture from recent rain or snow, which would mean hot, dry conditions should reduce evapotranspiration while leaving river flows relatively constant.

But recent studies have uncovered a "drought paradox": Plants actually maintain, or even increase, transpiration during dry periods.

To untangle this paradox, Reed Maxwell and Harry Stone, environmental engineers at Princeton University's High Meadows Environmental Institute, installed an array of sensors across a 200-acre (81 hectares) area of the East River watershed in Colorado, which feeds into the Colorado River. The sensors measured water movement through the snowmelt-to-streamflow pathway over two years: 2023, which had a high snowpack but a hot, dry summer; and 2024, which had a moderate snowpack followed by a cool, wet summer.

They found that even during hot, dry periods ‪—‬ when soil moisture was at record lows ‪—‬ evapotranspiration remained high. This suggests that plants were tapping into groundwater reserves when soil moisture was low, using water that would otherwise end up in the river.

"Dry summer, wet summer; they're getting their water," Maxwell told Live Science. "But they're finding it from other sources. They're taking it from shallow groundwater."

Historical temperature and streamflow data also showed that summer temperatures affected the streamflow regardless of how much snow had fallen the previous winter. Snowmelt efficiency, the ability for a given amount of snowmelt to produce a certain amount of runoff, has declined over the past century, so the same storm produces less water in the reservoirs as time goes on. It's unclear exactly what is driving this shift, but climate change is a part of it.

"We see that across the Upper Colorado River Basin; a warm summer will actually take a big snowmelt and make it like an average snowmelt because of the additional water demands from plants," Maxwell said. "Plants are still meeting their needs; they're just using other water sources, and those sources are taking away from the water that would end up in our reservoirs."

The work was published as a preprint article, meaning it has not yet undergone peer review or been published in a scientific journal.

Brad Udall, a senior water and climate research scientist at Colorado State University who was not involved in the research, said a major strength of the work was that the researchers directly measured changes in evapotranspiration on an hourly basis, rather than relying solely on computer models.

The findings support a hypothesis that Udall and others are actively investigating: that increased evapotranspiration brought on by higher temperatures is contributing to reduced river flows, he said.

Over the past century, temperatures in the Colorado River Basin have risen by 2.5 degrees Fahrenheit (1.4 degrees Celsius), according to the study. Over the past seven years, water flow in the basin has dropped by 35%, Udall said. He and others have hypothesized that there will be "increased reductions in flow due to these higher temperatures going forward," Udall told Live Science.

That could have major impacts on how much water is available for the people who depend on the Colorado River in the future. "It means there will be a lot less water, and we're already seeing it," Udall said. "We could see a 40% decline by mid-century."

New management rules for how water is shared between the upper and lower basin are supposed to go into effect next year. But so far, there is no agreement on what these rules should look like, Udall said. Rising temperatures, declining river flows, and decreases in precipitation will only complicate those negotiations.

While this study is just one piece of how the water cycle in the Upper Colorado River Basin works, it could have important impacts on decisions about water use in the future, Maxwell said. As summers get drier and warmer, we will have to recalibrate our understanding of how much water might be available in the Colorado River, even in years with big snowfalls.

"A better water budget that takes into account increases in summer transpiration is a really important factor when figuring out how much water there is in the basin, before we start to divide it up," he said.

Editor's note: This article was updated at 8.39 a.m. ET on March 19 to correct the picture caption for the second image to say it shows the East River, a tributary of the Colorado River. It was updated again at 12:50 p.m. ET on March 19 to change the top caption from Colorado to Utah.

The Cerrado savanna occupies about 26% of Brazil and is home to more than 12,000 plant species and diverse animal life. It's also speckled with groundwater-fed wetlands that serve as the headwaters for two-thirds of Brazil's major waterways, including the Amazon River, making it not only a biodiversity hot spot but also a critical ecosystem to preserve water security in the region.

This savanna's wetlands also have another superpower: storing carbon in their waterlogged soils. According to a new paper published today in New Phytologist, the Cerrado's wetlands store carbon at a density about six times greater than the Amazon rainforest's vegetation.

The Cerrado's wetlands "are probably one of the most important ecosystems in the Americas to accumulate carbon," said Larissa Verona, lead author of the new study and an ecologist at the Universidade Estadual de Campinas in Brazil and the Cary Institute of Ecosystem Studies. "But this carbon is vulnerable."

The team's findings underscore the need to protect these critically important ecosystems, especially as land use changes, agriculture, and climate change threaten to degrade the dark, wet soil and release its carbon into the atmosphere.

Digging for carbon

Previous studies in the Cerrado indicated that its soils held high amounts of carbon. But researchers typically did not dig deeper than about a meter [three feet] or expand their sampling beyond a few high-elevation areas in the region. The carbon storage potential of the savanna had been overlooked because its groundwater-fed wetlands aren't easy to spot from aboveground, said Amy Zanne, an ecologist at the Cary Institute of Ecosystem Studies and coauthor of the new study.

Because the ecosystems had been so overlooked, their carbon-storing potential has not been included in Brazil's national carbon accounting, either, said Rafael Oliveira, an ecologist at Universidade Estadual de Campinas in Brazil and coauthor of the new paper. Without detailed scientific information, "we have no clue what the emissions are" when these wetlands are degraded. "What are we losing in terms of carbon?" he asked.

To answer that question, Verona and the research team extracted meters-long soil cores from across seven sites in the Cerrado, then tested the layers of those soil cores to determine how much carbon was stored in each. The study's data richness makes an important contribution, said Julie Loisel, a peatland ecologist at the University of Nevada, Reno, who was not involved in the new study. "It's filling a really big data gap," she said. "In terms of the importance of wetlands in the tropics to understand modern-day carbon cycles, most of our information comes from satellite-derived products. We have very little information from field science."

"It's really nice to see a study that has gone really above and beyond in terms of measurements."

The researchers found that on average, each layer of the soil cores stored carbon at a density of 1,200 metric tons of carbon per hectare. That was a surprisingly high number for the types of soils tested, Loisel said. Though scholarly descriptions differ, one classical definition of peat — the type of carbon-rich soil usually considered in carbon accounting — requires that soils consist of about 30% organic matter; the soils studied by the research team contained about 16%, on average. Still, the amount of carbon stored in the Cerrado soils was much higher than that in some peatlands because the Cerrado soils were so dense, Loisel said.

"These are substantial carbon sinks," she said, adding that research like the new study "opens interesting research questions about understanding carbon dynamics in the continuum between mineral soils, wetland soils, and peat soils."

These dense, carbon-rich soils do not occur throughout the entire Cerrado, though, so Verona and the research team set out to estimate the complete geographic range of the wetlands using remote sensing data on land cover, land use information from landowners, and a machine learning approach. They estimated that these ecosystems cover 16.7 million hectares, about 8% of the total area of the Cerrado.

Next, the team measured greenhouse gas emissions from the Cerrado's soil during the wet, dry, and transitional seasons. They found that about 70% of wetland emissions occurred during the dry season. That may pose a problem as the climate changes and the wetlands dry out — because a steady influx of water maintains the environment that allows the soil to store so much carbon, drought could release a lot of carbon quickly.

Protecting tropical wetlands

Further analysis of the soils using radiocarbon dating determined that on average, the carbon stored in the Cerrado is more than 11,000 years old, with the oldest dated to be 20,000 years old. The age of the carbon stored indicates how critical ecosystem protections are: "If we lose the carbon in the Cerrado that has accumulated for millennia, we can't put it back so easily," Zanne said.

Though Brazilian law provides legal protections for wetland areas, the laws don't necessarily protect the water sources that feed the wetlands and make them a critical carbon-storing system. "We need to maintain the hydraulic dynamic," Verona said. "If you protect only the wetlands per se and don't protect the water in the landscape…we will lose the hydraulic system."

Furthermore, Verona refers to the Cerrado as a "sacrifice biome" because it absorbs some of the water-intensive land use needs that can't occur in the better-protected Amazon rainforest. To Verona, that's counterintuitive: "If you sacrifice the Cerrado for agriculture so that you can protect the Amazon, then you remove part of the water that flows to the Amazon, which [was] protecting the Amazon."

Keeping the Cerrado's wetlands functional could be critical to meeting global climate targets, however. Better protections — such as laws that recognize the connectivity of groundwater to the wetlands and better water usage laws — could help to maintain the Cerrado's carbon-storing capacity.

"We are just losing a lot of these wetlands silently, invisibly," Oliveira said. "They remain invisible in policy in Brazil, and even for the global scientific community. They really deserve urgent, stronger protection and recognition at the global level."

This article was originally published on Eos.org. Read the original article.

Forecasters predict that a potentially supercharged El Niño is coming this summer, and it could push temperatures across the globe to unprecedented extremes.

Last week, the National Oceanic and Atmospheric Administration's (NOAA) Climate Prediction Center announced that there is a 62% chance of El Niño emerging between June and August. In other words, El Niño is more likely than not this year.

El Niño is the warm phase of the El Niño-Southern Oscillation (ENSO), a natural climate pattern of atmospheric and sea temperature changes in the tropical Pacific Ocean. During El Niño, warmer waters gather east of the equatorial Pacific, forcing the jet stream south. This brings warmer and drier conditions to the northern U.S., while the Gulf Coast and southeastern U.S. have an increased risk of flooding.

The tropical Pacific Ocean is currently in the midst of La Niña, the cold phase of ENSO, when sea surface temperatures fall at least 0.9 degrees Fahrenheit (0.5 degrees Celsius) below the long-term average. La Niña is expected to end in the coming weeks as the sea warms, according to the latest Climate Prediction Center announcement. El Niño will then occur if sea surface temperatures reach and remain at least 0.9 F above the long-term average.

If El Niño does emerge as anticipated, it could intensify into a "super El Niño," AccuWeather reported. A super El Niño occurs when sea surface temperatures reach at least 3.6 F (2 C) above the long-term average.

"Intensity is uncertain but there is potential for a moderate to possibly strong El Niño this fall into winter," Paul Pastelok, a meteorologist and lead U.S. long-range forecaster at AccuWeather, said, per the weather website.

Accuweather's forecasters estimate that there's a 15% chance of a super El Niño developing by the end of the hurricane season in November. Meanwhile, NOAA's Climate Prediction Center gives a 1-in-3 chance of a strong El Niño emerging between October and December but describes the potential strength as "very uncertain."

El Niño tends to strengthen hurricane activity over the central and eastern Pacific while suppressing hurricanes in the Atlantic, which typically leads to a less-active hurricane season overall.

The ENSO cycle triggers a warm El Niño and then a cold La Niña every two to seven years, on average. However, they aren't always on time. Equally, while each phase tends to last around nine to 12 months, their duration varies.

Earth was last in El Niño between May 2023 and March 2024. On that occasion, El Niño was close to being a super El Niño, but while sea surface temperatures breached the 3.6 F threshold, they didn't remain above the threshold for long enough to qualify. The last super El Niño occurred in 2015-2016.

The last El Niño contributed to record-breaking heat in 2023 and 2024, with 2024 currently the hottest year on record. If El Niño emerges in 2026, then the year will get warmer, but is unlikely to be as hot as 2024 — we started the year in La Niña, after all. Global temperatures in 2027, however, could be pushed to record-breaking heights, according to a post on the social media platform X by Zeke Hausfather, a climate scientist and energy systems analyst.

"The El Nino cometh," Hausfather wrote. "This would push up our estimate for 2026 global temperatures (though its still unlikely to surpass 2024 as the warmest year), and make 2027 very likely to be the warmest year on record given the historical lag b/w ENSO and surface temp."

It's important to remember that a variety of factors influence the weather and climate. The planet is already warming due to climate change and will continue to do so, regardless of what ENSO is doing.

Blackwater lakes and rivers in the Congo Basin are releasing ancient carbon into the atmosphere, a new study shows. Previously, scientists thought this carbon was safely stored in the surrounding peatlands, but the research reveals that's not the case.

The finding contradicts the long-held assumption that old peat carbon remains trapped underground, suggesting that some tropical peatlands could switch from being carbon sinks to major carbon sources.

"We are now faced with a 30-million-tonne question: we need to determine if this is just a small, natural leakage of ancient carbon, or the onset of broadscale destabilization," study lead author Travis Drake, a carbon biogeochemist at the Swiss Federal Institute of Technology Zurich (ETH Zurich), told Live Science in an email.

Drake and his colleagues have conducted three research trips to the Congo Basin over the past four years. Specifically, the team traveled to the Cuvette Centrale, a 56,000-square-mile (145,000 square kilometers) region of forests and swamps in the Democratic Republic of the Congo that holds Earth's largest known tropical peatland complex. Situated in the heart and to the south of the Cuvette Centrale are two large blackwater lakes — Lake Mai Ndombe and Lake Tumba — while a major blackwater river, the Ruki River, flows west-northwest across it to meet the Congo River.

Blackwater lakes and rivers contain high levels of decaying plant debris, or dissolved organic carbon, which gives them their black color. This dissolved organic matter, together with direct inputs of carbon dioxide (CO2) from the surrounding swamps and forests, creates supersaturated concentrations of CO2 in lakes Mai Ndombe and Tumba and in the Ruki River. As a result, these waters emit enormous amounts of CO2 into the atmosphere.

Crucially, however, none of the CO2 was previously thought to originate from the Cuvette Centrale's ancient peat, as these deposits, protected from decomposition by their oxygen-depleted, waterlogged environment, were believed to be highly stable.

But in a paper published Feb. 23 in the journal Nature Geoscience, Drake and his colleagues found otherwise. Their results showed that a significant proportion of the CO2 escaping the Cuvette Centrale's blackwater bodies is from peat carbon that is between 2,170 and 3,500 years old.

"We were very surprised because we fully expected the carbon dioxide to be modern," Drake said.

The researchers drew their conclusions from measurements they took at Lake Mai Ndombe in 2022 and 2024, and at Lake Tumba and the Ruki River in 2025. They accessed Lake Mai Ndombe with small boats, which was difficult due to strong winds that almost capsized them, Drake said.

"The ecosystems remain in relatively pristine condition," he said. "There are some small settlements and villages scattered around Lake Mai Ndombe, but they are far and few between."

The team measured sediments, greenhouse gases, dissolved organic carbon and dissolved inorganic carbon, which includes dissolved CO2, bicarbonate ions (HCO3–) and carbonate ions (CO32-). Later, in the lab, the researchers analyzed their samples with high-precision spectrometry to separate modern carbon from plants and older carbon from soils.

"Because the organic carbon in the lake was modern, we assumed the inorganic carbon would be too, so we initially just analyzed a single sample to confirm," Drake said. But when about 40% of the inorganic carbon in that sample turned out to be millennia old, the team decided to test the remaining samples.

The results were consistent across Lake Mai Ndombe, so the researchers returned to the Cuvette Centrale to sample Lake Tumba and the Ruki River. Both contained high levels of inorganic carbon derived from ancient peat, suggesting that microbes in the region are breaking down peat carbon into CO2 and methane, which then seep into lakes and rivers before wafting into the atmosphere.

The Cuvette Centrale is estimated to hold one-third of the carbon stored in tropical peatlands globally, equivalent to about 33 billion tons (30 billion metric tons). It's possible that recent losses of ancient peat carbon are linked to the formation of new peat deposits, in which case the phenomenon might be nature returning to a state of equilibrium, according to the study. But it's also possible that climate change is destabilizing long-buried deposits and that the Congo Basin's peatlands are nearing a tipping point.

"This pathway highlights a critical vulnerability," Drake said. "If the region experiences future drought, this export mechanism could accelerate, potentially tipping these massive carbon reservoirs from a sink into a major source to the atmosphere."

Next, the researchers will analyze water trapped in the Congo Basin's peat to explore if and how microbes are releasing ancient carbon.

"Ultimately, we aim to confirm whether this process is happening across the entire Cuvette Centrale and quantify oxidation rates to determine if this leakage is a natural baseline or a sign of instability in this large carbon reservoir," Drake said.