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

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.

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.

The Gulf Stream holds tantalizing clues about when other key Atlantic Ocean currents could collapse due to climate change, a new study finds.

Originating in the Gulf of Mexico and leaving the U.S. East Coast near Cape Hatteras in North Carolina, the Gulf Stream is a branch of the Atlantic Meridional Overturning Circulation (AMOC) — a giant system of ocean currents that brings heat to the Northern Hemisphere and Europe, in particular.

A growing body of evidence suggests that the AMOC is weakening and speeding toward a "tipping point," which could completely transform the climate in many parts of the world, including Northwest Europe and tropical monsoon regions. When the AMOC might collapse is uncertain, but an early warning signal hidden within the Gulf Stream could help scientists predict the event years before it happens, the new research shows.

"First, you have this very gradual northward drift [of the Gulf Stream], which is related to some AMOC weakening, but apparently there is also this jump when the AMOC is getting too weak, which is this early warning indicator," study lead author René van Westen, a postdoctoral researcher in climate physics at Utrecht University in the Netherlands, told Live Science.

Unlike other currents that form the AMOC, the Gulf Stream is wind-driven. After passing by Florida, it follows the U.S. East Coast northward to Cape Hatteras and then veers east into the North Atlantic Ocean. Although the Gulf Stream is a surface current, its position is controlled by much deeper currents that also belong to the AMOC and create tight vortices when they interact with the layers above. These spirals push the Gulf Stream as a whole southward — but as the AMOC weakens and the vortices loosen, the Gulf Stream may start to drift northward.

To explore these effects further, van Westen and Henk Dijkstra, a professor of physical oceanography at Utrecht University, simulated an AMOC collapse in an ocean model with a very high resolution over the Gulf Stream. In the climate models typically used to study the AMOC, the Gulf Stream "is smoothed out, so you hardly see any features and the dynamics are not well captured," van Westen said.

The researchers triggered an AMOC collapse in the model that was much more gradual than the collapse humans may be causing by heating Earth and accelerating Arctic ice melt, which prevents the formation of deep ocean currents. They observed the Gulf Stream's response in unprecedented detail, revealing for the first time an extremely abrupt, northward shift of the current 25 years before the start of the collapse.

The results were published Feb. 26 in the journal Communications Earth & Environment.

The researchers found two stages in the Gulf Stream's response, both measured off Cape Hatteras at 71.5 degrees west longitude. First, as the AMOC gradually weakened over 392 simulated years, the Gulf Stream inched northward by 83 miles (133 kilometers). Second, as the AMOC continued to weaken over two more simulated years, the Gulf Stream suddenly jumped north by 136 miles (219 km). This abrupt shift happened just 25 years before the start of the AMOC collapse, suggesting it could be used as an early warning signal to predict the collapse.

While the two stages may be realistic, it's unlikely that the time lag between the abrupt Gulf Stream shift and an AMOC collapse would actually be 25 years in real life, van Westen said. That's because the model didn't account for global temperature rise, which is accelerating the collapse of the AMOC; the model only simulated an increase in fresh water in the North Atlantic.

A northward drift of the Gulf Stream has implications for ocean ecosystems that are presently north of the current in colder waters but may soon end up south of the current in warmer waters. The drift may also exacerbate sea level rise along the East Coast, van Westen said.

Already underway

Next, the researchers analyzed satellite data to determine whether the Gulf Stream has already begun shifting northward. "We found this relationship within our climate model, and now the next step was to look whether those results appear in observations," van Westen said. "What we found in observations is that, yes, indeed, the Gulf Stream has shifted northward over the past three decades."

This finding is more evidence that the AMOC is weakening and means we are in the first stage of the Gulf Stream's response, van Westen said. Natural climate and atmospheric variability may have contributed to the slow drift, but those contributions are small relative to the AMOC's weakening, he added.

It is unclear when the transition to the second stage of the Gulf Stream's response will occur, but satellites are in place to detect this switch if and when it happens. The next task for researchers is to work out the true lag time between this second stage and the AMOC collapse so that the second stage can serve as a robust warning indicator, van Westen said.

The study is the most in-depth analysis of the potential impacts of an AMOC collapse on the Gulf Stream to date, but there are some caveats, said Maya Ben-Yami, a climate tipping point researcher at the Technical University of Munich and the Potsdam Institute for Climate Impact Research in Germany who was not involved in the research.

"This paper definitely points at Gulf Stream changes as a possible warning signal, but a lot more work would need to be done to confirm that, for example by looking across different models," Ben-Yami told Live Science in an email.

It's possible that the abrupt northward shift could happen without the AMOC collapsing down the line, in which case it may not be an early warning indicator but rather a response to the weakening, she said.

Additionally, the rate of AMOC weakening in the study was likely slower than what can be expected under future warming conditions, meaning that the 25-year lag time could shrink to "almost nothing" and come too late to be an actionable warning signal, Ben-Yami said.

"Personally I think that it's also useful to have a signal that just tells you 'the tipping point has been crossed' without earlier warning, but I'd say we still don't know if Gulf Stream changes could be either type of signal," she said.

Between the 17th and 20th centuries, humans killed millions of whales for oil. They stripped their blubber, spinning the iconic creatures in the water and pulling off the fat in a huge spiral like the peel of an apple. The blubber was boiled into oil, then strained into barrels to be used in everything from oil lamps to industrial lubricants.

This was the bloody process that brought light to society.

"It is horrible," Charles Nordhoff wrote of his experience on a whaling vessel in 1895. "Yet old whalemen delight in it. The fetid smoke is incense to their nostrils. The filthy oil seems to them a glorious representative of prospective dollars and delights."

For over 100 years, the voracious hunger for whale blubber drove blue, humpback and North Atlantic right whales to the brink of extinction.

Now, commercial whaling is all but banned, whale blubber is used in just a handful of products, and whale populations have rebounded somewhat.

A similar sea change is coming for petroleum, though when and how it will play out is still incredibly hazy.

The best superforecasters, combined with machine learning, are only accurate at predicting geopolitical events up to a year in advance, Luke Kemp, research affiliate with the Centre for the Study of Existential Risk and at the University of Cambridge, told Live Science. At best, "we have general pictures we can paint."

But the general trends are clear. We've already transitioned much of our home energy use away from oil. And as climate change pushes us to accelerate that transition, we're developing new technologies that will help the world outgrow its oil dependence ever faster, experts say. In a few industries, like shipping and plastic, the decayed bones of long-dead animals will be the primary energy source for a long time to come.

But a post-oil world is coming.

"The whaling industry is a very good analogy," David MacDonald, a professor of petroleum geology at the University of Aberdeen in the U.K., told Live Science. At its peak, "The whaling industry was huge." But over the decades, "it was an inexorable decline," he said.

Origins of oil

Humans have been using oil for millennia. In fact, around 40,000 years ago, people in what is now Syria used bitumen — a byproduct of crude oil — to stick handles onto their tools. Fast-forward 35,000 years, and the Mesopotamians used the same sticky substance to waterproof their boats. The Babylonians used it to build the Hanging Gardens, and the Egyptians used it to embalm mummies.

In China, people burned crude oil and gas for heat and light as early as 500 B.C. By the fourth century A.D., they were drilling for these natural resources and transporting it via bamboo pipes.

But it wasn't until 1859, when Edwin "Colonel" Drake struck it big in Pennsylvania, that oil was sought at scale. With the same, albeit modernized drilling technique used in China more than 1,500 years earlier, Drake hit a reservoir 69.5 feet (21 meters) down, and the U.S. oil industry was born.

Crude oil, which is composed of simple strings of carbon and hydrogen, forms from the remains of animals and plants that sank to the bottom of swamps, lakes and oceans. Over millions of years, layers of sand and rock covered them, and intense heat and pressure turned these remains into oil and natural gas. They were then locked away in reservoirs — some close to the surface, others thousands of feet below — with gas sitting atop a lake of oil.

For the past 165 years, crude oil has transformed virtually every aspect of society.

If oil vanished tomorrow, global trade would break down as the shipping and aviation industries ground to a halt. Food security would be precarious, with no petroleum to fuel large-scale agriculture or packaging to keep food fresh. Medical care would be set back generations without the sterile equipment needed in hospitals. Renewable energy projects would be frozen without the components required to make solar panels or wind turbines.

Planes, trains, boats and automobiles

Our transition away from oil will be far gentler than that, of course. We've largely stopped using oil for electricity. In October last year, a report by the International Energy Authority found demand for oil will peak this decade.

The rise of electric vehicles (EVs) will usher in the next big drop in oil use.

Currently, road vehicles make up almost 50% of global crude oil use, according to a 2018 report by the International Energy Agency (IEA). But this percentage will plummet in the coming decades. It's estimated that EV sales will account for over two-thirds of the global market by 2030. If we are particularly aggressive in slashing fossil fuel emissions by three-quarters by 2050, the EV industry could be responsible "for more than half of the reduction in total oil demand," according to the BP Energy Outlook 2023, which forecasts future fuel use.

In 50 years, most of this car-driven oil usage could be eliminated.

Aviation also largely relies on oil for fuel. Planes last decades and cost tens of millions to hundreds of millions of dollars to build. But technology is moving fast in this sector. New aircraft are far more fuel efficient than aircraft were 40 years ago, and the industry is engaged in reaching net-zero emissions by 2050.

Sustainable aviation fuels (SAFs) will be key to ditching oil. These biofuels are derived from the raw materials used for industrial processes, including waste, biomass, cooking oil and animal fat waste. SAFs have the added benefit of being compatible with current aircraft engines, and they can be blended up to 50% with traditional jet fuel. Boeing plans to make all of its commercial aircraft capable of flying on SAFs by 2030. By 2050, if we aggressively cut carbon emissions, SAFs will account for between 30% and 45% of aviation fuels, BP estimates.

Shipping is a more stubborn problem. Ships run on oil. Like planes, they are wildly expensive to build, last decades and will be hard to phase out. Around 90% of world trade is carried out by the international shipping industry, with over 105,000 merchant ships currently sailing the oceans and accounting for around 5% of oil consumption today.

Without ships transporting goods all over Earth, "half the world would starve and the other half would freeze," according to the International Chamber of Shipping. The problem for this industry is, you can't just change the fuel.

Fredric Bauer, an associate senior lecturer at Lund University in Sweden, researches low-carbon innovation in energy and industrial systems. He's not convinced the shipping industry will be able to transition away from oil anytime soon. The International Maritime Organization published its first climate strategy in 2018 and has generally been "incredibly conservative" in shifting away from fossil fuels, Bauer said.

Hydrogen is a potential alternative fuel. Ships could be retrofitted with hydrogen fuel cells, but that strategy comes with problems. For example, to remain liquid, the fuel must be stored at extremely low temperatures. Its energy density is low, increasing the amount of storage required on each ship. Hydrogen is also extremely explosive.

Hydrogen-powered ships are still in their very early stages. The first ferries and small ships using this technology are being tested, but large, hydrogen-fueled oceanic cargo ships are still in the design phase.

Jay Apt, a professor at Carnegie Mellon University's Tepper School of Business and the Department of Engineering and Public Policy, told Live Science that shipping will likely be a voracious oil user for decades.

"If I was to look into the cloudy crystal ball, I would say that long-haul shipping would be one of the large-scale uses of petroleum that we would see 100 years from now," Apt said.

Plastic fantastic 

Single-use plastics are littering Earth in ever-increasing quantities. They take hundreds of years to degrade and then become microplastics, which are choking the ocean, littering the tops of mountains and congregating inside our bodies.

"The use of plastic is in many ways the more dangerous part of the oil industry, rather than the burning of hydrocarbons," MacDonald said. "If humanity disappeared from Earth tonight, in 1,000 years the levels of CO2 in the atmosphere will be back to normal — whatever normal is — but there would be plastic in the oceans and soils for millions of years."

Synthetic plastic is made from oil, and it is extremely cheap to produce.

Around 12% of the oil extracted today goes toward the petrochemical industry, which makes plastic and fertilizers, along with clothing, medical equipment, detergents and tires. And this number is set to grow: The Organization for Economic Co-operation and Development estimates that under current policies, the global use of plastics could triple by 2060.

Plastic is extremely useful because its density can be varied. We can try to move away from plastic in products like food packaging, but phasing out medical plastic is more challenging. Plastic is everywhere in hospitals, including in disposable syringes, IV bags, catheters, gloves and bed linens. It's not just that plastic is cheap, durable and malleable. It's also sterile, so helps curb the spread of infections.

"I couldn't even imagine health care without plastics, and I don't even think we should go there," Dr. Jodi Sherman, founding director of the Yale Program on Healthcare Environmental Sustainability, told Live Science. "I would argue that plastic has allowed very important innovation of medical devices and supplies, and is here to stay."

Right now, primary plastics are "ridiculously and unsustainably cheap," so oil-free alternatives can't compete on cost, Bauer said.

Bioplastics, made from crops, could provide a way forward, MacDonald said. But the story of biofuels serves as a cautionary tale. Soybean fields have taken over large swaths of U.S. farmland — in part because of its use as a biofuel.

"We have a finite amount of agricultural land," MacDonald said. "If we turn a lot of it over to growing fuels, what do we do about feeding people? It's not an easy equation. Everything is related and interlinked."

The beginning of the end of oil

"The oil industry isn't going to collapse because we run out of oil, there's plenty of oil left," MacDonald said.

But at some point, clean energy technologies will become so cheap that it won't pay off to drill and extract oil.

The first method to be phased out will be wildcat drilling, in which an area with unproven reserves is explored, MacDonald said. This is risky and extremely costly if you don't find anything. Even drilling new wells in areas with known oil reserves is eye-wateringly expensive: Companies spend tens to hundreds of millions to get wells and rigs staffed up and running, and then it's years before they turn a profit.

"You're spending money like a drunken sailor in the hope you're going to get some money back," MacDonald said. "It ain't a quick process. That's why oil companies are big — they have to be as they're carrying a huge amount of risk."

Still, oil wells will continue to pump in the vast sand fields of Saudi Arabia for decades. In the U.S., production will continue at high levels through 2050.

Femke Nijsse, a complexity scientist at the University of Exeter in the U.K. whose research focuses on modeling climate, energy systems and the economy, told Live Science she's hopeful that global oil use will be cut by 95% by 2065, with aviation and shipping as the remaining strongholds.

MacDonald predicts a "less spectacular" decline, falling a quarter by 2050. "At some point you'll get to a cliff where it will go down quite rapidly," he added.

Some experts can't imagine a post-oil future at all. Kevin Book, managing director of ClearView, a research firm that looks at energy trends, told Live Science that artificial intelligence and geoengineering will change oil extraction and refining, but that oil won't disappear until a technology that doesn't exist yet, like fusion energy, makes it obsolete.

But the push for decarbonization means oil will eventually become a flash in the pan in our history. Like industrial whaling, our taste for it will dissipate until just a few small strongholds remain.

Fifty to 100 years from now, oil derricks and drilling fields in the U.S. may start to look like the abandoned mine museums and gold-rush ghost towns that litter the American West — tourist attractions that paint a picture of a lost way of life, an economy firmly in the past.

Climate change is shifting wildfire seasons in North America, but the direction of the shift depends on the regional ecosystem, a new study shows.

The fire season in the northern boreal forests of Alaska and Canada have shifted forward, on average; prairie regions have seen little change; and the fire season in the arid West and California has extended further into late fall and winter. The findings were published Feb. 24 in the journal Geophysical Research Letters.

"It's very region-specific," said Hongliang Zhang, an environmental scientist at Fudan University in China. Understanding these specific shifts are important for managing wildfires and preparing resources for the worst parts of the fire season, Zhang told Live Science. Seasonal patterns are also important for predicting the health impacts of wildfire smoke, which can be severe.

Zhang and his colleagues used data on burn area in North America from 2001 to 2020 taken from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Aqua and Terra satellites. They also gathered data on meteorological variables, vegetation, lightning potential and other environmental factors at the time of the fires.

They found that the boreal forest, or taiga, of Canada, Alaska and the Great Lakes region is seeing earlier fires. This is due to earlier snowmelt, and thus earlier dryness of fuels. Canada experienced its worst wildfire season in 2023 and its second-worst just two years later.

The warm desert Southwest and the Mediterranean-like climate region of California saw a lengthening of the fire season, with more fires burning after the traditional high-risk window.

Prairies and grasslands experienced slight changes in fire season intensity and minimal change in seasonal timing. The Appalachians and Southeastern forests also saw little in the way of seasonal shifts.

The researchers also modeled future scenarios. Under a high-emissions climate change scenario, they found, the fire season in boreal forests will shift forward by about a week, while California's annual fire season could extend more than a month later than the current June-to-October window. The desert Southwest could see a similar stretching of the fire season, the researchers wrote.

This model will be useful for more detailed study, Zhang said. He and his team plan to use it to study the impacts of other factors, such as vegetation change and human activities. (According to the National Park Service, 85% of wildland fires in the U.S. are caused by human acts, such as arson or failing to extinguish a campfire correctly.) The model is also useful for predicting the pollution and carbon emissions from these fires, Zhang said.

"That model is really good at predicting wildfire," he said. "So now we want to predict the emissions of wildfire to the atmosphere."

The rate of global warming has accelerated at a higher level since 2015 than in any decade since records began in 1880, according to a new study that removes the background "noise" of natural fluctuations. However, not everyone agrees with the paper's findings.

In the study, published Friday (March 6) in the journal Geophysical Research Letters, researchers used statistical evidence to demonstrate accelerated warming in the past decade, which they say is the first time that scientists have identified the "statistically significant acceleration of global warming" since 2015.

"The warming trend nearly doubled after 2014," study co-author Stefan Rahmstorf, head of Earth system analysis at the Potsdam Institute for Climate Impact Research in Germany, told Live Science in an email. "The acceleration of the global warming rate means we will cross the 1.5°C [2.7 degrees Fahrenheit] limit earlier," he said, adding that they were surprised by the drastic surge.

Between 1970 and 2015, the average warming rate was pegged at just under 0.2 degrees Celsius (0.36 F) per decade. But over the last 10 years, the researchers found that the estimated warming rate was 0.35 C (0.63 F) per decade. There has also been a consistent upward trend in the global mean surface temperature, according to the study.

Researchers generally attest that the magnitude and rate of warming over the past 150 years have surpassed the magnitude and rate of changes experienced over the past 24,000 years, which includes the end of the last ice age.

But it's tricky to tease out how much of this accelerated warming is due to human-made greenhouse gas emissions and how much can be attributed to natural influences on the climate, such as El Niño. Rahmstorf and his co-author Grant Foster, a retired climate analyst, wanted to remove these natural fluctuations to better understand the warming trend.

"The key was to reduce the 'noise' in the data, i.e. to remove the effect of natural variability, to get a better signal-to-noise ratio," Rahmstorf said, explaining that this gives the signal increased visibility.

Rahmstorf and Grant used five established global temperature datasets, including those from NASA; the National Oceanic and Atmospheric Administration; and Berkeley Earth. Then, they removed three environmental factors that drive warming — the El Niño-Southern Oscillation cycle, volcanic eruptions and solar variations — and tested the datasets for acceleration in warming since 1970.

The findings showed an acceleration of global warming, they said. Finally, they estimated warming rates by developing a model that looked at changes every decade since 1895.

The results showed a "statistically significant acceleration of global warming since about the year 2015," they wrote in the study. In a statement, Rahmstorf said the certainty rate was 98% and was consistent across datasets and analysis methods.

If the current rate of warming continues, he added, this paper and previous research has shown that we will pass 1.5 C (2.7 F) warming by 2030.

Disagreement in the field

But not all researchers are convinced by Rahmstorf and Grant's findings. Their methods for removing these variables from their analysis are imperfect and may leave residual effects, Zeke Hausfather, a research scientist at Berkeley Earth, told Live Science. He argued in a paper published last year that anthropogenic or human activities are increasing the Earth's surface temperature. This has further been linked to faster sea level rise and land precipitation change.

"There is widespread agreement that there has been a detectable acceleration in warming in recent years," he said. "But it remains unclear how much of the additional warming over the past decade in particular is a forced response [or] an unforced variability."

Robert Lund, a statistician at the University of California, Santa Cruz, also agrees there is solid evidence that the Earth is warming, but was less sure if we're experiencing an accelerated warming rate. Lund, who applies the laws of probability to climate change models, was among the authors of the 2024 paper that argued that a recent surge in the rate of global warming was not yet detectable. Despite the hot years of 2023 and 2024, he told Live Science, we need to urge caution while claiming that the Earth is suddenly getting warmer. "There is no statistical evidence of that," he said.

Lund found issues with various aspects in the analysis, such as including factors like El Niño. He said that one would also have to account for the uncertainties caused by them, since models cannot yet capture the intricate atmosphere-ocean interactions. However, the authors did not do this, he noted.

While Lund and Hausfather are cautious of the warming trend, they agree that we are inching closer to surpassing the thresholds established in the Paris Agreement, which aims to hold the rate of global warming to 2 C above preindustrial levels and pursue efforts to limit the increase to 1.5 C above preindustrial levels.

The Earth seems to already be on the track for this, as a recent Emissions Gap Report found that the planet will speed past the 1.5 C threshold in the next decade. This could double the share of people being exposed to extreme heat, Live Science reported last November.

For Rahmstorf, this study also serves as a warning. "We need to become a lot faster in replacing fossil fuels like coal, oil and gas and leaving them behind altogether," he said.

Planting trees along coastlines with human-made shore defenses, such as dikes, could protect more than 140,000 people from flooding and save up to $800 million from flood damage globally each year, a new study finds.

Places that have mangroves, such as parts of Florida, are better able to withstand the ravages of storms and their powerful waves. But although there is a push to restore mangroves around the world, there are several challenges.

In 2022, Hurricane Ian slammed into southwest Florida. Storm-powered waves reached up to 18 feet (5.5 meters) and devastated coastal communities and infrastructure. The hurricane killed 158 people and generated $110 billion in damage in the state. Authorities say the storm surge, which is when the storm pushes water ashore, was the main cause of deaths.

But places in Florida with mangroves saw 30% less damage than areas without mangroves, saving about $13 billion. "Mangroves act as a sponge to incoming waves," Daniel Friess, an environmental scientist at Tulane University, told Live Science. "Their dense tangle of aboveground roots are great at soaking up incoming wave energy."

Mangroves are forests that exist in the intertidal zone between the ocean and land. Their trees can live in the salty water, and they are found in tropical and subtropical coastal zones.

Climate change is expected to make hurricanes more frequent, and rising sea levels will drive higher storm surges. Mangroves protect communities and infrastructure from these surges.

They could also help to combat climate change. A 2025 study found that restoring 1.1 million hectares (2.7 million acres) of mangroves globally would remove about 0.93 gigatons of carbon dioxide from the atmosphere. That's almost triple the emissions from cars in the U.S. It would cost about $10.73 billion to restore those mangroves, according to the study.

Despite their importance, the world's mangroves are in danger. More than half of Earth's mangrove ecosystems are at risk of collapse by 2050, according to a 2024 assessment by the International Union for Conservation of Nature. They are being replaced by agriculture and aquaculture.

Balancing costs and benefits

Researchers wanted to see how mangrove restoration around the world could protect people and prevent costly damage from floods, as well as determine where these measures might have the greatest impact.

In the study, published Jan. 20 in the journal PNAS, they modeled the effects of mangroves when the forests were combined with flood defenses, such as dikes or seawalls. Dikes are human-made structures that run alongside the ocean or rivers to stop water from overflowing onto land.

"We used a published mangrove restoration tool, which looks into where the mangroves have been lost based on satellite data, the hydrological conditions of those areas now" to determine whether those mangroves could be restored, study lead author Timothy Tiggeloven, a climate adaptation specialist at Vrije Universiteit Amsterdam, told Live Science. Then, the team combined that information with flood risk, future climate scenarios, changes in GDP and population, and sea-level rise.

They found that mangrove-dike systems could save a total of $800 million globally and protect 140,000 people from flooding each year. These numbers increased under different climate scenarios linked to human carbon emissions.

Their cost-benefit analysis suggests that in a high-emissions scenario, in which Earth's climate changes dramatically, every dollar spent on mangrove dike systems globally could ultimately generate — or save — $6. That could translate to as much as $125 billion by 2100.

The benefits were not the same everywhere, though. Countries in Southeast Asia would see the greatest benefits — about $270 million a year and 70,000 people shielded from flooding. West Africa was a close second, saving about $221 million and protecting 38,000 people. Nationally, Nigeria, India and Indonesia would benefit the most from restoring mangroves in front of human-made coastal defenses.

In the U.S., Florida would see significant benefits from restoring its mangroves, but Louisiana would get even greater returns, the study found.

Jonah Busch, an environmental economist and a former senior research fellow at the Center for Global Development who was not involved in the research, welcomed the study. "It combines the biophysical analysis of mangrove restoration with the engineering of dikes, and then economics," he said.

However, he would have liked to see a breakdown of the financial benefits of mangroves on their own. "They're assuming that places already have dikes and then you can add mangroves on top of that," he said.

The authors flagged this as a limitation of the study. The analysis relies on a flood-protection database, which lists existing infrastructure, and cannot say whether the dikes are strong enough or even still standing.

Gray-green strategies

Adaptation strategies that combine nature-based solutions and engineered infrastructure are sometimes called gray-green infrastructure. This area is "a new, open and important topic," Busch said.

Other examples include combining forest management with home hardening (which involves retrofitting or building houses with flame-retardant materials) to lower fire risk, and marrying dam maintenance with upstream watershed restoration.

"There is no doubt that a hybrid approach can be a pragmatic and effective approach" to coastal management, Thomas Westhoff, a nature-based solutions officer at the conservation nonprofit Wetlands International, told Live Science. That was especially the case along heavily urbanized, subsiding coastlines that have lost much of their mangrove cover, he added.

Westoff cautioned that there is no one-size-fits-all solution. "Whether this is a feasible solution is very context specific," he said, adding that dikes may not exist in many areas.

However, "in many regions, healthy mangrove belts can still provide enough of a buffer for coasts and communities as the climate changes," Westhoff said.

Challenges of restoring mangroves

There is a global push to restore mangroves, but a majority of these projects — up to 80% — fail.

"Restoring mangroves is a good idea, but these projects are difficult to implement," Tiggeloven said. Mangroves are sometimes planted in unsuitable places, or the wrong types of trees are planted.

Successful projects require community buy-in, Westhoff said. "When communities benefit directly from restored ecosystems — whether through sustainable harvesting or ecotourism — they are more likely to protect them for the future."

Plus, when restoring or preserving a mangrove, people may want to develop the land in other, more profitable ways, Busch noted.

"Mangroves have to compete with that from an economic perspective," he said. The new paper "is a key part of that, because it shows the economic value of mangroves' storm protection."

Agriculture is a cornerstone of India's economy, employing between 40% and 50% of the country's workforce, while providing food for over a billion people. But it's increasingly under threat from extreme weather events linked to climate change. Between 2015 and 2021, India lost 83.8 million acres (33.9 million hectares) to floods and excess rain, and 86.5 million acres (35 million hectares) to drought.

India's farmers are mainly smallholders — but these small farms, fragmented across the country, are heterogeneous and have limited data. This makes it hard to devise policies that can account for how they are being impacted by extreme weather events.

Meha Jain, an associate professor of geospatial data sciences, food systems and the University of Michigan, has spent nearly 20 years working with farmers in India to understand the threats they are facing and how they are adapting.

"I just realized more and more that humans can't be considered to be separate from the environment," she told Live Science.

Jain's pioneering research combines field interviews with satellite-based mapping tools to determine how farmers are reacting and adapting to these growing pressures.

Her research focuses on how agricultural production by smallholder farmers can be made sustainable, productive and importantly, resilient to unpredictable weather. Having worked in the field with farmers, from 2021 to 2023, she then used historical data on groundwater availability and insights garnered from working with farmers to ascertain how cropping patterns are changing under a warming climate.

With this, she's working on scaling up those rich individual accounts from farmers, by leveraging satellite and remote-sensing tools to understand what is happening at a regional or national scale. She hopes this will further inform how we devise policies that can future-proof agricultural production in the face of a changing climate.

For her work, Jain has now been awarded the inaugural ASU-Science Prize for Transformational Impact, which recognises research that not only advances knowledge but also makes an important contribution to society.

She spoke to Live Science about her ability to forge a link between the people on the ground and actionable solutions to reduce the environmental impact on food systems.

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

What shaped the kind of research you do today?

I spent a year in India doing research on the ground and spent a lot of time with smallholder farmers. I became very interested in climate change impacts on agriculture and how people adapt. Seeing how important agriculture was for daily livelihoods, and how uncertain and precarious agriculture had become in these times, it just made me feel very passionate about working on this issue.

Initially, when I started my work, I spent a lot of time asking them how they were being impacted by climate change and how they were adapting. I learnt how to do remote sensing to use satellite images to scale what I was seeing, to regional and national scales. Now, what I'm really interested in doing is thinking about how we can use those satellite datasets to better identify and target interventions to help farmers further adapt.

How does your work on the ground with farmers inform the more quantitative aspect of your work, i.e satellite imagery and agricultural datasets?

Our work now focuses on the IGP region [the Indo-Gangetic Plains (IGP), spanning across the states of Punjab, Haryana, Uttar Pradesh and Bihar] , because that's the main breadbasket. That is where a large proportion of the rice and wheat for India is produced. We identify which data products are of interest to produce by spending time on the ground.

For example, [I heard] many farmers say that they were increasing irrigation as temperatures warmed. Then we decided to understand how big an issue that is, how much of that is occurring across the country of India. We then developed satellite datasets to measure irrigation. That is where we spend time on the ground and use that to inform the datasets we produce in the lab.

How did this field work and daily interactions with farmers help you identify the gaps with your data, or did it complement the data that you already had? Is this knowledge transferable across other farming regions in the tropics?

The satellite data, while it's really powerful for understanding patterns at large scales, doesn't allow you to really understand the drivers of decision-making behind the patterns you see. So we really rely on our household surveys — large-scale quantitative data — to understand those options.

While a bulk of our work, probably 70% of it, takes place in India, we are expanding our work to other countries. We're taking a similar approach and working with partners in Mexico, Colombia, Zambia and different smallholder systems across the tropics.

As climate change is primarily characterized by unpredictability, how does your research work towards adapting or mitigating that?

There are two ways. One is that with the satellite data, we can get a long-term historical understanding of cropping practices for about 20 years. Then we can put them into our models to understand how, in the past, when a certain weather event happened, what did people do? What was the impact?

The other way they can help is with real-time monitoring. We can look at the vegetation growth curves of crops within a season. For instance, our work has largely focused on wheat across the IGP. We also have some new work about rice and wheat in central India. We largely focus on grain crops because they're the primary staple for livelihoods and are also easier to map using satellite data.

You have dealt with datasets that map groundwater availability, climate change and cropping patterns. How can this help inform mitigation or adaptation in the face of extreme weather events, heat waves, drought, and floods, especially those that affect farmers in India and other South Asian countries?

The challenge when we use historical data to understand how people are adapting is that we can only say how they've adapted to what has happened in the past. But obviously, conditions are changing — extreme events are becoming more frequent. So definitely more work is needed in this space, because maybe taking what we learned historically wouldn't exactly apply in the future. I think this is an important research question.

How does this research expand over the next few years?

The types of projects I'm really excited about now are projects where we use satellite data to target and inform intervention, which is more action-oriented. To give an example, I have some work where we're trying to see if we can use satellite data to pick up the lowest-yielding fields, and eventually target interventions [in those regions in India].

​​Antarctica, which is nearly four times the size of the United States, is almost entirely covered by a miles-thick layer of ice.

But the South Pole hasn't always been frozen. So when was the last time Antarctica was ice-free?

This ice cap formed relatively recently in geological terms, experts told Live Science. "I think most people would say 34 million years ago was when the ice sheet first formed in Antarctica," said Eric Wolff, a paleoclimatologist at the University of Cambridge. "[Previously] most of it would have been like northern Canada today — tundra and coniferous forest."

Global temperatures are a key factor influencing the extent of ice coverage. Around 50 million years ago, the world was about 25 degrees Fahrenheit (14 degrees Celsius) warmer than it is today, but temperatures steadily decreased over the following 16 million years. By 34 million years ago — a time period known as the Eocene-Oligocene boundary — the climate was 14.4 F (8 C) warmer than it is today.

But what triggered this temperature drop, and was that all it took for the ice sheets to form?

Related: Which is colder: The North or South Pole?

"There are two factors, and probably both were in play," Wolff told Live Science. "One of them is a change in the carbon dioxide concentration of the atmosphere, and the other is the movements of the continents and, in particular, the opening up of the Drake Passage," the strait between South America and Antarctica that connects the South Atlantic with the South Pacific.

The more carbon dioxide that's in the atmosphere, the more heat is trapped and the warmer the planet is.

From about 60 million to 50 million years ago, the carbon dioxide concentration in Earth's atmosphere was really high — somewhere around 1,000 to 2,000 parts per million, or between 2.5 to 5 times today's levels, said Tina van de Flierdt, a geochemist at Imperial College London.

"But we know that the CO2 in the atmosphere came down across that Eocene-Oligocene boundary," she told Live Science. This decrease in atmospheric CO2 would have been accompanied by a cooling of the global climate, she added, probably tipping Earth over a threshold and allowing ice sheets to form.

However, there was also likely localized cooling on the Antarctic continent due to plate tectonics, Wolff said. Around this time, South America and Antarctica finally separated, opening up what's now the Drake Passage.

"This led to what we call a circumpolar current — water going right around Antarctica in a circle," Wolff said. "This isolates Antarctica from the rest of the world and makes it much harder for warm air masses to get across the Southern Ocean and, therefore, makes Antarctica colder."

Plate tectonics also directly influenced carbon dioxide levels, he added. Rock weathering and volcanic activity are both part of the carbon cycle, so over thousands of years, geological processes can shift the balance of gases in the atmosphere.

Although some uncertainty remains, researchers are fairly confident about this transition 34 million years ago thanks to the chemical signatures in rock sediments. Oxygen atoms exist in two forms: oxygen-16 (common oxygen) and oxygen-18 (heavy oxygen). Continental ice contains a higher proportion of the lighter oxygen-16, meaning the oceans — and, therefore, the shells of small sea creatures — contain a higher percentage of oxygen-18 when ice sheets are bigger.

"By looking at the oxygen isotopes in the carbonate shells of small sea creatures in ocean sediments, you see a jump around 34 million years ago, which people take as being because the [lighter] oxygen isotope is going onto the continent of Antarctica," Wolff explained.

As for whether Antarctica could ever be ice-free again, "It's definitely possible, van de Flierdt said. "Planet Earth has done it before. Planet Earth could do it again." While it's unlikely that human activity will lead to the complete melting of the ice sheet, it's important we do everything possible to limit the loss of ice from the Antarctic now, she added. "It's in our hands to avoid the worst-case scenario," van de Flierdt said.

Editor's note: This story was originally published on Sept. 8, 2024.

The Trump administration took a major step in its efforts to unravel America's climate policies on Feb. 12, 2026, when it moved to rescind the 2009 endangerment finding — a formal determination that six greenhouse gases that drive climate change, including carbon dioxide and methane from burning fossil fuels, endanger public health and welfare.

But the administrations arguments in dismissing the health risks of climate change are not only factually wrong, they're deeply dangerous to Americans' health and safety.

As physicians, epidemiologists and environmental health scientists, we've seen growing evidence of the connections between climate change and harm to people's health. Here's a look at the health risks everyone face from climate change.

Extreme heat

Greenhouse gases from vehicles, power plants and other sources accumulate in the atmosphere, trapping heat and holding it close to Earth's surface like a blanket. Too much of it causes global temperatures to rise, leaving more people exposed to dangerous heat more often.

Most people who get minor heat illnesses will recover, but more extreme exposure, especially without enough hydration and a way to cool off, can be fatal. People who work outside, are elderly or have underlying illnesses such as heart, lung or kidney diseases are often at the greatest risk.

Heat deaths have been rising globally, up 23% from the 1990s to the 2010s, when the average year saw more than half a million heat-related deaths. Here in the U.S., the 2021 Pacific Northwest heat dome killed hundreds of people.

Climate scientists predict that with advancing climate change, many areas of the world, including U.S. cities such as Miami, Houston, Phoenix and Las Vegas, will confront many more days each year hot enough to threaten human survival.

Extreme weather

Warmer air holds more moisture, so climate change brings increasing rainfall and storm intensity and worsening flooding, as many U.S. communities have experienced in recent years. Warmer ocean water also fuels more powerful hurricanes.

Increased flooding carries health risks, including drownings, injuries and water contamination from human pathogens and toxic chemicals. People cleaning out flooded homes also face risks from mold exposure, injuries and mental distress.

Climate change also worsens droughts, disrupting food supplies and causing respiratory illness from dust. Rising temperatures and aridity dry out forests and grasslands, making them a setup for wildfires.

Air pollution

Wildfires, along with other climate effects, are worsening air quality around the country.

Wildfire smoke is a toxic soup of microscopic particles (known as fine particulate matter, or PM2.5) that can penetrate deep in the lungs and hazardous compounds such as lead, formaldehyde and dioxins generated when homes, cars and other materials burn at high temperatures. Smoke plumes can travel thousands of miles downwind and trigger heart attacks and elevate lung cancer risks, among other harms.

Meanwhile, warmer conditions favor the formation of ground-level ozone, a heart and lung irritant. Burning of fossil fuels also generates dangerous air pollutants that cause a long list of health problems, including heart attacks, strokes, asthma flare-ups and lung cancer.

Infectious diseases

Because they are cold-blooded organisms, insects are directly influenced by temperature. So with rising temperatures, mosquito biting rates rise as well. Warming also accelerates the development of disease agents that mosquitoes transmit.

Mosquito-borne dengue fever has turned up in Florida, Texas, Hawaii, Arizona and California. New York state just saw its first locally acquired case of chikungunya virus, also transmitted by mosquitoes.

And it's not just insect-borne infections. Warmer temperatures increase diarrhea and foodborne illness from Vibrio cholerae and other bacteria and heavy rainfall increases sewage-contaminated stormwater overflows into lakes and streams. At the other water extreme, drought in the desert Southwest increases the risk of coccidioidomycosis, a fungal infection known as valley fever.

Other impacts

Climate change threatens health in numerous other ways. Longer pollen seasons increase allergen exposures. Lower crop yields reduce access to nutritious foods.

Mental health also suffers, with anxiety, depression and post-traumatic stress following disasters, and increased rates of violent crime and suicide tied to high-temperature days.

Young children, older adults, pregnant women and people with preexisting medical conditions are among the highest-risk groups. Lower-income people also face greater risk because of higher rates of chronic disease, higher exposures to climate hazards and fewer resources for protection, medical care and recovery from disasters.

Policy-based evidence-making

The evidence linking climate change with health has grown considerably since 2009. Today, it is incontrovertible.

Studies show that heat, air pollution, disease spread and food insecurity linked to climate change are worsening and costing millions of lives around the world each year. This evidence also aligns with Americans' lived experiences. Anybody who has fallen ill during a heat wave, struggled while breathing wildfire smoke or been injured cleaning up from a hurricane knows that climate change can threaten human health.

Yet the Trump administration is willfully ignoring this evidence in proclaiming that climate change does not endanger health.

Its move to rescind the 2009 endangerment finding, which underpins many climate regulations, fits with a broader set of policy measures, including cutting support for renewable energy and subsidizing fossil fuel industries that endanger public health. In addition to rescinding the endangerment finding, the Trump administration also moved to roll back emissions limits on vehicles — the leading source of U.S. carbon emissions and a major contributor to air pollutants such as PM2.5 and ozone.

It's not just about endangerment

The evidence is clear: Climate change endangers human health. But there's a flip side to the story.

When governments work to reduce the causes of climate change, they help tackle some of the world's biggest health challenges. Cleaner vehicles and cleaner electricity mean cleaner air — and less heart and lung disease. More walking and cycling on safe sidewalks and bike paths mean more physical activity and lower chronic disease risks. The list goes on. By confronting climate change, we promote good health.

To really make America healthy, in our view, the nation should acknowledge the facts behind the endangerment finding and double down on our transition from fossil fuels to a healthy, clean energy future.

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

Methane is a greenhouse gas around 30 times more potent than carbon dioxide and has been increasing in concentration in the atmosphere since measurements began. However, in 2020 scientists were bemused by a sudden unexplained spike in atmospheric levels. With so many possible sources and sinks of this gas, untangling the origins of this anomaly has proven a complex task but researchers think they may now have solved the mystery.

The unprecedented spike in atmospheric methane in 2020 was actually caused principally by reduced human emissions during the pandemic, which temporarily stopped the atmosphere from breaking down the gas, according to a new study.

Lower levels of nitrous oxides — which are released by combustion engines in cars, among other sources — weakened the atmosphere's natural cleanup capability. This, in turn, prompted a dramatic surge in methane as travel ground to a halt in early 2020, and returned to pre-pandemic levels in 2023 as society went back to normal.

The study, reported in the journal Science Feb. 5, combined satellite data, ground station measurements and complex models to untangle the possible sources of the extra gas. It also identified a substantial increase in natural emissions as a secondary contributor to the methane spike.

Atmospheric methane has been increasing steadily since records began, but measurements taken in 2019-2020 revealed an alarming acceleration in this trend. The annual increase almost doubled, reaching 16.2 parts per billion, compared with a more moderate rise of 8.6 parts per billion over the previous 10 years. In the years since, various hypotheses have been put forward to explain this unexpected spike — including rising fossil fuel use, wetland and agricultural emissions, wildfires, and changes in atmospheric chemistry — but untangling which factors were actually responsible is an immensely complex task.

Taking a comprehensive approach, the researchers combined physical data from across the globe with modeling studies and simulations to evaluate the potential contribution of each source.

Their analysis revealed that a staggering 83% of 2020's methane peak likely resulted from a reduction in the atmosphere's ability to remove methane — a phenomenon directly tied to the disruption of human activities caused by the pandemic.

Oxidizing 'all the nasties'

Specifically, the sudden drop in industrial emissions — most notably, toxic nitrous oxides — dramatically decreased the production of hydroxy (OH) radicals in the atmosphere.

"OH is the cleanup molecule of the atmosphere," Euan Nisbet, a professor of Earth sciences at Royal Holloway University of London who was not involved in the research but wrote an accompanying perspectives article on the findings, told Live Science. "It oxidizes all the nasties — it turns carbon monoxide to CO₂, and by grabbing hydrogens, it turns methane into CO₂."

The team fed satellite data about the precursor molecules to OH into a model to map the concentration and distribution of these cleansing radicals between 2019 and 2023. This revealed a sharp decrease in 2020, which is consistent with the observed rise in methane levels. Then, they compared this result with a second model, generated from measured emissions and wind patterns, further confirming the hypothesis that reduced human emissions were the main contributor to elevated methane.

However, cautioned Nisbet, this doesn’t mean that fossil fuel use is the answer to rising methane levels. Although a less potent greenhouse gas, CO₂ persists much longer in the atmosphere so a move to cleaner fuels is still an urgent priority.

The remaining 20% of the spike was therefore the result of direct methane emissions. Working backward from satellite measurements, climate data and isotope ratios, the team created a series of additional "inversion" models to pinpoint the precise source of these emissions.

The relative levels of carbon-12 and carbon-13 isotopes — both versions of carbon with different chemical masses — were particularly crucial to this process. "The sources affect the isotopes, so you've got to fit the isotope data as well," Nisbet said.

Biology prefers to use lighter carbon-12, meaning biological sources of methane, such as cattle or wetlands, have a different effect on the proportions of carbon-12 and carbon-13 in the atmosphere than geological sources like fossil fuels do, Nisbet explained.

"So one of the conclusions to come out of this is that the fossil fuel methane emissions are relatively static," he said. "On the other hand, the biological emissions have grown quite strongly, and that's most probably in wet Africa."

The observed increase in methane emissions between 2020 and 2023 coincided with extremely wet conditions across tropical Africa that resulted from an unusually extended La Niña period and the Indian Ocean Dipole climate oscillation.

"Over recent years, it's been causing huge amounts of rainfall in East Africa, particularly the Nile basin that then floods the Sudd, which is one of the most productive wetlands in the world," Nisbet said. "Very wet and very warm means big swamps — cows, antelope and buffalo, and a lot of papyrus growing, dying, rotting and turning into methane."

In 2023, the end of both the pandemic and the wet La Niña conditions across the tropics saw methane increases stabilize back to pre-2020 levels. But while the world appears to have recovered from this temporary blip, that it happened at all is an urgent call to action, Nisbet said.

"It's a first indicator of the state of the global climate," Nisbet said. "Methane has a period of 10 years, so it's turning over all the time and telling us there's something big going on. This is a climate feedback and the big biological sources are turning on, so we've got to work twice as hard."

Canada could remove more than five times its annual carbon emissions from the atmosphere by the end of the century by planting trees along the northern edge of its boreal forest, a new study suggests.

In recent decades forests have slowly moved north in response to climate change — in particular the taiga area on the edge of the boreal forest, the massive belt of forest stretching across northern Canada, Europe, and Russia, where it transitions to Arctic tundra. This movement suggests a potential way to boost carbon sequestration in the area, said study lead author Kevin Dsouza, a postdoctoral researcher in Earth and environmental sciences at the University of Waterloo in Canada.

"What is the potential for reforestation in these regions, and how much carbon could they sequester?" he told Live Science.

In the new study, his team used satellite data to identify forest composition and empty spaces in the northern boreal forest, and ran simulations using models from the forestry industry that included fire probabilities, climate variables, seedling mortality and land type to estimate how much carbon the ecosystem could sequester over the next 75 years.

The simulations identified around 6.4 million hectares (15.8 million acres) of land suitable for reforestation — an area about twice the size of Vancouver Island — across Canada's north. Planting trees on this land would remove almost 4 gigatons of carbon from the atmosphere by 2100, about five times Canada's current annual emissions. But that 6.4 million hectares is a fairly conservative estimate of the available land, Dsouza said. Scaling it up to 32 million hectares (79 million acres) could sequester almost 20 gigatons.

The work was published Nov. 13, 2025, in the journal Communications Earth & Environment.

Canada did have an ambitious plan to plant 2 billion trees by 2031, but it was canceled last year. As of June 2025, 228 million trees had been planted, and the government plans to honor other agreements that should see 988 million trees planted across the country.

Dsouza said the 2 billion-tree plan ran into trouble due to complicated logistics and a lack of funding, rather than any problem with the science of reforestation. "It wasn't planned well, just trying to hit a number is not the right strategy," he said. "It needs to be more strategic, planting in the right places, with economic and community benefits so it is sustainable."

Focusing on northern areas could have the added benefit of helping to stabilize permafrost, which can release huge amounts of methane — a much more potent greenhouse gas than carbon dioxide — when it thaws, Dsouza added.

Longer term thinking needed

However, a separate team of experts disagrees with this solution and has instead proposed another way to use trees to reduce CO₂.

Ulf Büntgen ,professor of Environmental Systems Analysis at the University of Cambridge in the U.K. who was not involved in the research, told Live Science that while planting trees is good for removing carbon in the short term, few advocates consider the longer term problem of carbon storage.

"Planting trees is good but it's not solving anything, it's just buying time," he said. "While the tree is growing it helps, but eventually it will die and release the carbon again."

In a study published Jan. 3 in the journal NPJ Climate Action, Büntgen and his colleagues proposed a more long-term solution: cutting down trees in the boreal forest and sinking them deep in the Arctic Ocean. They suggest targeting large mature trees in specific plots of land in Canada, Russia and Alaska, which are most susceptible to fire and store carbon less efficiently than younger trees. The deep, cold and oxygen-poor water of the Arctic Ocean would preserve the trees, and the carbon they contain, for thousands of years, he said. The harvested areas could then be replanted with new trees to restart the carbon-capturing cycle.

The team suggested that managing just 1% of the boreal forest in this way would remove 1 gigaton of carbon dioxide from the atmosphere each year.

"There's already a lot of carbon in the timber that naturally finds its way to the ocean," he said. "We could accelerate this natural process."

Carbon dioxide emissions from China have flatlined or fallen for 21 months, meaning the world's biggest greenhouse gas emitter may have reached a global turning point sooner than expected.

China's carbon dioxide (CO2) emissions dropped by 1% in the last quarter of 2025 and likely by 0.3% over the whole year, keeping them just beneath the record highs reached in May 2024, according to a new analysis by the Finland-based Centre for Research on Energy and Clean Air (CREA) for Carbon Brief. The nearly two-year flatline or fall is the longest on record not driven by an economic slowdown in the country, which emits over a third of global CO2.

If the trend holds, China's emissions could reach an all-time peak before 2030 — the country's official target date — or even sooner, marking a key win in the global effort to curb fossil fuel use and slow global warming. Yet whether the drop is sustained or demand will drive a rebound in emissions before the officially targeted peak remains an open question.

"CO2 emissions fell year-on-year in almost all major sectors in 2025, including transport (3%), power (1.5%) and building materials (7%)," Lauri Myllyvirta, lead author of the analysis and co-founder of CREA, wrote on Bluesky. "The key exception was the chemicals industry, where emissions grew 12%."

"The numbers imply that China's carbon intensity — its fossil-fuel emissions per unit of GDP — fell by only 12% during 2020-25, short of the 18% target," Myllyvirta added. "China now needs to cut carbon intensity by around 23% over the next five years in order to meet its Paris [Agreement] commitments."

Driving the trend are China's development of renewable energy technologies and electrified transport, alongside dropping demand for cement and steel. China is the world's largest producer of both commodities, accounting for around 48% and 54% of the global production of cement and steel, respectively, with each contributing roughly 15% to the country's total greenhouse gas emissions.

The plateau also occurred despite a growth in China's power consumption by 520 terawatt hours (TWh) in 2025, according to the CREA analysis. That's because clean energy production grew to match power consumption, with solar power output increasing by 43%, wind by 14% and nuclear 8% year over year, offering roughly 530 TWh of new power. Energy storage capacity also grew by a record 75 gigawatts (GW), outpacing the 55 GW growth in demand.

But whether this plateau holds, temporarily rebounds or dips into permanent decline will hinge on decisions made by the Chinese government in its next five-year plan in March.

CREA's analysis notes some ambiguity in the CCP's planning. An explainer for the upcoming plan refers to a "plateau" in coal consumption from 2027, suggesting that absolute reductions in emissions may have to wait until after 2030.

"Moreover, allowing coal consumption in the power sector to grow beyond the peak of overall coal use and emissions implies slowing down China's clean-energy boom," the CREA report says. So far, the boom has continued to exceed official targets by a wide margin." Clean energy technologies drove more than a third of China's economic growth in 2025.

China is complementing its clean energy investments with ecological engineering projects that include planting trees around the Taklamakan Desert, which has turned one of the world's largest and driest deserts into a carbon sink.

Meanwhile, today (Feb. 12), the Trump administration is set to revoke the 2009 "endangerment finding," which established a legal mechanism to regulate U.S. greenhouse gas emissions. And on Wednesday (Feb. 11), Washington Coal Club gave Trump the "Undisputed Champion of Coal" award a day after he issued executive orders for the U.S. Department of Defense to buy coal-generated electricity.