A simple method to thicken Arctic sea ice has shown promising results in its very first field experiment, performed in Cambridge Bay, Nunavut, Canada.

Researchers are considering several controversial geoengineering techniques to slow the catastrophic melt of Arctic sea ice, including stratospheric aerosol injection, which involves shooting tiny sulfur particles into the sky to blot out the sun. But in a new study, scientists evaluated the merits of a much safer and more straightforward approach: pumping seawater onto existing sea ice in winter and letting it freeze into a reinforcing layer.

Known as sea ice thickening, this method has been used by Nordic and Arctic communities for decades, and ice hockey rinks employ a similar technique to keep their ice sturdy, two of the study's authors told Live Science in an email.

"Practical applications [that already exist] include building ice roads and creating platforms for offshore oil exploration," said Edward Blanchard-Wrigglesworth, a research associate professor in the University of Washington's Department of Atmospheric Sciences, and Andrea Ceccolini, an honorary professor at University College London and the CEO of the startup Real Ice, which studies artificial sea ice thickening methods and receives funding from the U.K. government.

Modeling work hints that sea ice thickening could become a climate adaptation tool for Arctic communities by limiting coastal erosion near towns, facilitating travel and supporting animal migrations and hunting.

Now, researchers have assessed the method's efficacy in the field for the first time. Their results, published May 22 in the journal Earth's Future, indicate that both the thickness and brightness of sea ice can be enhanced significantly on small scales — making the ice more reflective, and therefore more resilient to melting.

In the experiment, the team set up eight test areas and three control sites in Cambridge Bay during the winter of 2024 to 2025. Using submersible pumps that each consume less power than a toaster, they flooded the test areas either once or twice with up to 8 inches (20 centimeters) of seawater, while the control sites were never flooded. In spring, one control site was used for a melt pond drainage experiment, which involved drilling small holes in the ice to remove meltwater and expose the brighter ice underneath.

Overall, the test areas grew up to 12.6 inches (32 cm) thicker than the control sites by the end of winter, which is roughly equivalent to the ice thinning that has happened in the Arctic over the past 50 years, according to the study. Test areas that were flooded twice showed greater thickening than those flooded once. And in the melt period from late May to September, sea ice in the test areas appeared brighter and had slower melt rates, remaining thicker than the ice in the control sites. The melt pond drainage experiment also resulted in brighter sea ice than the other control sites.

When water is pumped onto sea ice, it saturates the snow that sits on top of the ice. "The snow-water mixture freezes into a new layer of ice, while the reduction in snow insulation allows colder atmospheric temperatures to accelerate natural ice growth from below," Blanchard-Wrigglesworth and Ceccolini explained.

Thicker sea ice is usually brighter than thin sea ice, which boosts the amount of sunlight that is reflected back into space. "The broader implication is that these effects could enhance the Arctic's reflectivity through both increased surface brightness and longer-lasting sea ice," the researchers said. "If similar results could eventually be achieved at larger scales, increased Arctic albedo could contribute to regional cooling, with potential knock-on benefits such as slowing permafrost thaw and reducing ice loss from Greenland."

However, there is still a big question mark over how scalable and economically viable sea ice thickening is, given that it requires people and machines working in the field. According to a 2016 study, 10 million wind-powered pumps would be needed to cover just 10% of the Arctic Ocean, and 100 million to cover the entire Arctic. "It is reasonable to ask whether such an endeavor is financially feasible or even logistically possible," the authors of that study wrote.

Yearly sea ice extent in the Arctic has shrunk by 20% since 1979, and this loss is accelerating with global warming. Therefore, if we want Arctic sea ice thickening to work at a large scale, "the pumps must be deployed almost immediately, while there is still a sufficient area of sea ice over which to flood," researchers wrote in a 2021 study.

The ecological and social impacts of Arctic sea ice thickening are not well understood, and further research will delay deployment, meaning it might be too late to roll out sea ice thickening by the time scientists have the data they need to ensure its safety and feasibility.

For these reasons and others, including governance issues and high maintenance needs, "sea-ice thickening is simply not feasible for use at a scale and at a rate that would be meaningful for sea ice protection," researchers wrote in a review published last year.

Deployment on anything but local scales would be challenging, Blanchard-Wrigglesworth and Ceccolini agreed. Nevertheless, the researchers said their most recent winter trials, which have yet to be published, showed encouraging results. In those trials, the sea ice in test areas grew 20 inches (50 cm) thicker than in control sites, The Guardian reported.

"We expect to have a clearer picture once the current melt season is complete," the researchers told Live Science. "In parallel, we are developing underwater robotic technology that could support autonomous deployments. Earlier this year, we conducted the first Arctic field tests of a prototype re-icing drone in Finland."

The drone is currently being refined in collaboration with the BioRobotics Institute in Pisa, Italy, according to The Guardian.

Frozen droppings of prehistoric ground squirrels are chock-full of DNA from ice-age beasts, including woolly mammoths, a mysterious big cat and a huge array of other organisms, revealing a remarkably detailed genetic snapshot of ancient life in Canada's rugged Yukon.

Although the genetic material of large creatures was found in the ground squirrels' poop, these rodents were not carnivores. They were opportunistic omnivores that feasted on a wide variety of plant material and fungi, as well as insects, rodents and carrion, just like Arctic ground squirrels (Urocitellus parryii) do today in the Yukon Territory and other parts of northwestern North America and Siberia.

But Arctic ground squirrels also have a habit of collecting and storing various objects in their burrows, which may have introduced additional DNA into the droppings over time, potentially explaining some of the genetic signals detected, the researchers cautioned. It's also possible that carnivores' DNA ended up in the burrows because they were attempting to prey on the squirrels, they added.

"The Arctic ground squirrels that are in the Yukon today act kind of like pack rats," study first author Tyler Murchie, a paleogenomics researcher with the Hakai Institute in British Columbia, Canada, said in a statement. "So they'll go into the landscape, and they'll collect a whole bunch of different bits of plant material and bones, seeds, and they'll bring it back to their burrow."

So whether these ancient rodents were feasting on carrion and other edibles or simply bringing it into their homes, these dropping help reveal the flora and fauna that lived in Beringia, an ancient region that once encompassed northeastern Asia and northwestern North America when the continents were connected by a land bridge during the last ice age. The findings were published Tuesday (June 9) in the journal Nature Communications.

Poop detectives

For the study, the researchers analyzed samples extracted from the poop pellets, which had been preserved for millennia in burrows within the deep permafrost of the Yukon, which borders Alaska. These droppings, the oldest of which date to around 700,000 years ago, have yielded an extraordinary treasure trove of ancient environmental DNA from numerous plant, microbial, fungi and animal species.

Notably, the genetic material from the 700,000-year-old ground-squirrel droppings ranks among the oldest DNA ever recovered and sequenced, according to the authors.

"The research shows us that ground squirrel coprolites, or droppings, preserve remarkably diverse genetic snapshots of ancient Beringia, making them exceptional repositories for understanding evolutionary and ecological change through the deep past," study co-author Hendrik Poinar, director of the Ancient DNA Centre at McMaster University in Ontario, said in the statement.

"It helps reconstruct paleoenvironments in much deeper time, providing insights into environmental change, megafaunal evolution, dispersal and ultimately extinction," Poinar added.

During their investigation, the researchers extracted ancient environmental DNA from a collection of ground-squirrel coprolites. This provided the team with sufficient quantities of well-preserved genetic material to reassemble more than 18 mitochondrial genomes, including those of woolly mammoths (Mammuthus primigenius), the now-extinct steppe bison (Bison priscus), horses (Equus), the snowshoe hare (Lepus americanus) and the Arctic ground squirrel itself.

A mitochondrial genome, or mitogenome, is the complete set of DNA found inside mitochondria — small structures located within cells that generate energy. The mitogenome assembled from the 700,000-year-old sample represents the oldest mitogenome ever recovered from ancient feces, the study reports.

The team also detected weaker genetic fingerprints from a range of other animals in the coprolites, including evidence of lemmings (Lemmus), caribou (Rangifer tarandus), gray wolves (Canis lupis) and a big cat — possibly a cougar or the extinct American cheetah (Miracinonyx trumani) — as well as fungi, bacteria and more than 200 groups of plants.

Given the rich archive of genetic material that has been uncovered, the findings could pave the way for future discoveries, according to the researchers.

"The thing I hope people take away from this kind of work is the unexpected mystery that you could find in remains that you might otherwise overlook," Murchie said in a video statement.

How much do you know about Earth's frosty past? Find out with our last ice age quiz!

The Arctic Ocean has crossed a tipping point that is wreaking havoc on the region's food chain, with potentially dire consequences for commercial fishing and the ocean's capacity to soak up carbon, a new study reports.

Scientists found that vast areas of melting sea ice in the Arctic are leading to a significant reduction in nitrate, a key nutrient that forms the base of the marine food web and thus underpins important regional fisheries. As the ice disappears, more light hits the water's surface, promoting the growth of microscopic, plant-like organisms called phytoplankton. When phytoplankton die, their cells sink to the seafloor and are decomposed by nitrate- and oxygen-consuming bacteria.

The new study, published May 28 in the journal Communications Earth & Environment, found that the bacteria are consuming more nitrate than the Arctic ecosystem can withstand.

This effect, known as "denitrification," is irreversible under current climate conditions because we have passed a threshold where so much sunlight reaches the ocean that it's supercharging phytoplankton's productivity, said Marta Santos-García, a doctoral student of Arctic marine biogeochemistry at the University of Edinburgh in Scotland and the first author of the study.

"Even if sea ice were to increase temporarily, the Arctic nutrient system responds over much longer timescales," Santos-García told Live Science in an email. "Short-term increases in sea ice would be unlikely to rapidly reverse the decline in nitrate inventories, which may take much longer to recover."

Dropping nitrate levels may eventually come back to bite phytoplankton, because these tiny organisms need nitrate to carry out photosynthesis. As a result, the transition to a low-nitrate regime could accelerate climate change, as nitrate plays an essential role in the ocean's biological pump, which takes carbon dioxide from the atmosphere via photosynthesis and locks it away at depth when phytoplankton and the animals that eat it die.

"With nutrients such as nitrate in limited supply this mechanism cannot work effectively," Santos-García said.

To understand ecosystem changes in the Arctic, the researchers analyzed two decades of data from the Fram Strait, a passage between Greenland and Svalbard, Norway, that is the main gateway through which Arctic waters flow into the Atlantic Ocean. They found a sharp decline in nitrate levels in this region after 2009, which coincided with a dramatic reduction in Arctic sea ice and a gradual shift in phytoplankton communities toward smaller species that can cope with low nutrient levels.

"Shifts towards smaller phytoplankton have already been observed in parts of the Arctic, although these changes have not previously been linked to nitrate losses," Santos-García said. "This matters because smaller phytoplankton are generally less efficient at transferring energy up the food web. More of the energy is recycled within microbial communities rather than being passed on to larger zooplankton, fish, seabirds, and marine mammals."

Phytoplankton sit at the very bottom of the marine food chain, so the impacts of nitrate depletion will ripple through the Arctic ecosystem, impacting species at the highest levels. This could also affect fisheries in regions that depend on Arctic nutrient exports, such as the North Atlantic. But pinpointing what will happen in ecosystems downstream of the Arctic Ocean requires more research, Santos-García said.

For years, researchers thought the long-term impact of sea ice loss in the Arctic would be an increase in phytoplankton, because more organisms can bathe in sunlight and multiply when the sea ice extent is small. However, the increase in phytoplankton since 2009 has depleted nitrate levels enough to limit future phytoplankton growth.

Whereas phytoplankton proliferation used to be limited by how much sunlight reached surface waters, it is now controlled by nitrate levels. Therefore, nitrate must be considered as a key driver of future changes in the Arctic, Santos-García said.

"As nitrate is the nutrient that limits Arctic productivity, understanding these changes is therefore important not only for Arctic communities and ecosystems, but also for improving projections of future climate change," she said.

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!

Nearly 180 years after they died of cold and starvation in the Canadian Arctic, four crewmembers who perished in the Franklin expedition have been identified thanks to genetic analyses that matched their DNA with that of living descendants.

Three of the victims were from HMS Erebus, one of the expedition's two vessels, and died at Erebus Bay, the researchers reported in a new study published Wednesday (May 6) in the Journal of Archaeological Science: Reports. The fourth victim, a captain on HMS Terror, is the first from that ship to be identified with DNA, according to a second study that was published Thursday (May 7) in the journal Polar Record.

The findings reveal that "none of the men [from HMS Erebus] were alone when they died," the researchers wrote in the first of those studies, adding that "it is our hope that additional identifications can be made to provide that kind of information to other descendants." Based on the location of the bodies, researchers believe that other survivors were still alive and nearby.

The Franklin expedition departed England in May 1845, with an aim of discovering a Northwest Passage, an Arctic route to connect the Atlantic and Pacific oceans. Sir John Franklin commanded the mission's two ships. However, the ships and their 129 crewmembers became stuck in ice off a Canadian archipelago in late 1846, and Franklin died June 11, 1847.

On April 22, 1848, the surviving 105 crewmembers left the ships off King William Island and tried to make it to the Canadian mainland, walking and dragging boats on sleds, but all of them died along the way.

Search expeditions launched over the following two decades found some human remains and artifacts, as did scientific expeditions launched in the 20th and 21st centuries, which finally led to the discovery of the long-lost ships.

The new DNA analysis sheds light on exactly where each ship's crew traveled in their doomed attempt to find safety. One victim, Harry Peglar, was "Captain of the Foretop on HMS Terror," the team found in their research. Papers belonging to Peglar were found on another man's body in 1859 and include poetry and descriptions of events on board the ships.

Peglar's remains were discovered about 125 miles (200 kilometers) from the frozen ships, meaning he had made it far into the remote wilderness. "What is known is that he died alone, dressed in the uniform of a steward," the researchers wrote in the Polar Record study.

The other three newly identified individuals are William Orren, an able seaman on HMS Erebus; David Young, a boy first class on HMS Erebus; and John Bridgens, a subordinate officer's steward on HMS Erebus.

According to historical records, Orren first went to sea in 1821, when he was just 15 years old. He served on HMS Swan in 1830 and HMS Alfred in 1831. "He wouldn't sail with the navy again for another 14 years, until he joined the crew of HMS Erebus in Woolwich on 19 March 1845 as an Able Seaman when he was 38 years old," the team wrote in the first study.

Historical records also say Orren was about 5 feet, 4 inches (1.63 meters) tall, with dark hair, a light complexion and brown eyes. A descendant of his sister provided the DNA that allowed him to be identified.

Young was 17 years old when he joined HMS Erebus. His father was also a navy sailor but wasn't posted to the Erebus expedition. The DNA used to identify him came from a descendant of one of his brothers.

Bridgens was born in 1818, and his father was a sailor who never married his mother. Bridgens was trained by his stepfather to be a hairdresser, but he went to sea instead. Records indicate that he first went to sea as a musician in 1829. He served aboard HMS Endymion in 1841, during a war with China, and "volunteered for the Franklin expedition in Woolwich on 20 March 1845, when he was 26 years old," the team wrote in the article. The DNA of a descendant of one of his half-sisters was used to identify the remains of Bridgens.

"He was 5 ft 6 inches [1.68 m] tall, with dark hair and hazel eyes," the researchers wrote in the study. "His seaman's ticket indicates that he was illiterate, which is further demonstrated by his marking his name with a cross on his allotment records."

Previous DNA studies identified other members of the Franklin expedition, including John Gregory, an engineer on the Erebus, and James Fitzjames, who became captain of the Erebus after Franklin's death and was likely cannibalized.

"For the living descendants, these findings provide previously unavailable details regarding the circumstances and locations of their relatives' deaths, as well as the identities of some of the shipmates who died with them," Douglas Stenton, an anthropologist at the University of Waterloo in Ontario and first author of the Journal of Archaeological Science: Reports paper, said in a statement.

The team's work continues, and the remains of more crewmembers may be identified.

This striking satellite photo shows the point where a tiny lake bisects the snowy rim of a massive ancient glacier on a Canadian island in the Arctic Circle.

The small body of water, dubbed Gee Lake, is around 2 miles (3.2 kilometers) across at its widest point. It is located along the edge of the southeast limb of the Barnes Ice Cap — a roughly 2,300-square-mile (6,000 square kilometers), "bowling-pin-shaped" glacier situated at the center of Baffin Island in Canada's Nunavut territory.

In this image, captured in early September 2010, both the lake and the ice cap are still snow-free, except for the ice cap's edge, due to warmer summer temperatures. As a result, we can see the dark gray of the glacier, which is caused by the buildup of dust between layers of ice "spanning time periods that dwarf a human life," according to NASA's Earth Observatory. (In the winter, the glacier, lake and surrounding landscape are blanketed with snow.)

The exposed ice, which is up to 1,600 feet (500 meters) thick, is marked with striations that look like the "growth lines on a clamshell" running east to west, Earth Observatory representatives wrote.

These grooves are ridges cut by meltwater streams running off the glacier, Ted Scambos, a glaciologist at the University of Colorado Boulder and the National Snow and Ice Data Center, told the Earth Observatory. And while they give the impression that the ice is undulating, the surface of the glacier is surprisingly flat and smooth, he added.

Ice core samples collected from the glacier reveal that parts of the Barnes Ice Cap date back around 20,000 years, making it Canada's oldest known ice, according to a 2008 study. It is also the last remaining fragment of the Laurentide Ice Sheet, which covered most of Canada and the northern U.S. as far back as 100,000 years ago and helped to carve out the Great Lakes.

By around 20,000 years ago, as the last ice age began to thaw, most of the Laurentide Ice Sheet had melted away. But what was left slowly migrated north, toward what is now Baffin Island, where it eventually disappeared into the sea (aside from the Barnes Ice Cap). A 2009 study revealed that most of the melting ice passed through the Kangiqtualuk Uqquqti Fjord (previously known as the Sam Ford Fjord), around 70 miles (110 km) northeast of Gee Lake.

Although most of the Laurentide Ice Sheet is long gone, we can still see its impacts today. Recent research has shown that its meltwater has significantly altered ocean currents, while the geological "rebound" caused by the vanished weight that once pressed down on North America may be causing some major U.S. cities to sink and also affecting parts of Greenland.

Like most other glaciers in the Arctic and Antarctica, the Barnes Ice Cap is shrinking as a result of rising temperatures from human-caused climate change.

Although its current rate of ice loss is minimal — just a few meters of retreat per year — this will increase sharply as temperatures rise further. A 2017 study predicts that most of the glacier will "likely disappear in the next 300 years."

See more Earth from space

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."

Wildfires on Alaska's North Slope are more frequent and more severe now than they have been at any point over the past 3,000 years, research suggests.

The findings are based on satellite data and ancient charcoal fragments. The research team says the increase in blazes, driven by permafrost thaw and tundra "shrubification," constitutes a new wildfire regime that will likely intensify as global temperatures continue to rise.

Fires in northern Alaska "burn in summer, when the vegetation is snow-free and dry enough to ignite," study lead author Angelica Feurdean, a paleoecologist at Goethe University Frankfurt in Germany, told Live Science. In the past, this region was dominated by sedges and mosses, which provided little fuel for fires. But recently, there has been a shift toward woody shrubs, which are far more flammable and supply much more fodder for blazes, Feurdean said.

Researchers previously documented an increase in wildfires over recent decades on Alaska's North Slope and elsewhere in the Arctic, but the new study contextualizes these reports by examining wildfires over past millennia.

The research, published Nov. 10, 2025, in the journal Biogeosciences, reveals that the current peak in northern Alaskan fires started in the mid-20th century and hugely exceeds wildfire activity recorded as charcoal in local peatlands since about 1000 B.C. Global warming is behind the increase, the authors say, because rising temperatures create dry conditions on land as well as moisture in the atmosphere that boosts the risk of lightning, the main source of ignition in Alaska.

The soil samples in the study came from nine peatlands located between the Brooks Range and the Arctic Ocean. Many of these peatlands are covered in small shrubs and sphagnum moss (also known as peat moss), which only recently became widespread on Alaska's North Slope, where it replaced tussock-forming sedges such as Eriophorum vaginatum. Sphagnum moss can absorb moisture from the air, which is how it thrives despite drying conditions, Feurdean said. Sedges, on the other hand, need access to water in the soil to survive.

The samples were cores that measured about 1.6 feet (0.5 meters) long and encapsulated the past 3,000 years. The researchers analyzed the samples to reconstruct changes in vegetation, soil moisture and wildfire activity over time. Specifically, they inspected pollen and other plant remains; charcoal fragments; and tiny, single-celled organisms called testate amoebae, which are good indicators of water-table levels.

The researchers also analyzed satellite images of wildfires north of the Brooks Range between 1969 and 2023. When they combined these images with charcoal data to reconstruct the frequency and severity of fires, they found large discrepancies in the 2000s, when satellites captured huge fires but there was minimal charcoal evidence.

One explanation is that these fires were hotter than 930 degrees Fahrenheit (500 degrees Celsius) — the threshold above which charcoal turns to ash, Feurdean said. If that's the case, then the mismatch in the data over the past two decades suggests there has been an increase in extremely intense fires, she said.

Overall, the results showed a dramatic decline in soil moisture since about 1950 due to accelerating permafrost thaw, which causes surface water to sink into the ground. Plants that depend on shallow soil moisture, such as sedges and certain mosses, were replaced by shrubs — particularly shrubs in the heath family (Ericaceae) — and sphagnum moss, leading to an explosion in plant fuel for wildfires.

Combined with a rise in temperature and lightning strikes, these effects have culminated in the most severe wildfire activity in 3,000 years, Feurdean said.

Alaska's North Slope is likely a model for what is taking place across Arctic tundra ecosystems, and we can expect wildfires to worsen if warming continues, Feurdean added.

"If you have higher temperatures, you have higher shrub cover, more flammable biomass, and then more fires," she said. "The fires will continue to be more frequent and severe."

Editor's Note: This story was updated at 10:28 a.m. ET on Feb. 12 to clarify that only satellite data and charcoal fragments, and not other data sources, were used to look at past fire history.

Paleo-Inuit people reached remote islands in the High Arctic off the northwest coast of Greenland nearly 4,500 years ago, according to a new study that documents evidence of prehistoric dwellings there.

These early Arctic people, who had fine-tuned advanced watercraft technology and seafaring skills, repeatedly made the treacherous open-water journey to the islands to access vital maritime resources.

The island cluster of Kitsissut (also known as the Carey Islands) is the westernmost point of Greenland. Consisting of six small islands, Kitsissut is located at the heart of a rich marine environment called a polynya, which is a semipermanent area of open water in the middle of sea ice. Contemporary Inuit identified Kitsissut as an important place for hunting seabirds and accessing eggs, which prompted a team of archaeologists to investigate the islands for traces of prehistoric activity.

In a study published Monday (Feb. 9) in the journal Antiquity, researchers detailed the results of their archaeological survey of three of the islands. They found nearly 300 archaeological features in their survey, with the largest concentration being 15 Paleo-Inuit dwellings at the tip of Isbjørne Island. The dwellings suggested that people made the difficult journey from Greenland's mainland to Kitsissut numerous times.

The dwellings were identified by a ring of stones indicating the past presence of a tent with a hearth at the center. Based on an animal bone discovered in one of the tent rings, the archaeologists dated the occupation to around 4,000 to 4,475 years ago.

"In a regional perspective, it is a lot of tent rings in one place, indeed one of the largest concentrations," study lead author Matthew Walls, an archaeologist at the University of Calgary in Canada, told Live Science in an email. This suggests that Kitsissut and the polynya was "a place of return," Walls said. "It wasn't just a one-off visit by a family blown off course, for example."

It is unclear exactly how the Paleo-Inuit people arrived at Kitsissut, but the minimum journey from the mainland to the dwellings on Isbjørne Island is 33 miles (53 kilometers), the researchers wrote in the study. The route through the open sea is marked by erratic crosswinds, dense fog and powerful mixing currents — an extraordinarily risky journey that would have taken around 12 hours to complete in a wood-framed, skin-covered watercraft typical of Paleo-Inuit peoples.

"They are almost certainly visiting during the warm season, which doesn't last very long," Walls said. "The travel conditions also make it most likely that they are doing this in the brief summer."

Paleo-Inuit people probably headed to Kitsissut to hunt and gather eggs from the thick-billed murre (Uria lomvia), a polar seabird that nests in the thousands in the summer. The dwelling sites the archaeologists found are located directly below their nesting cliffs, Walls said, and there are numerous murre bones around the tent rings.

"The number of rings does give the sense that it is a whole community making the crossing, rather than a small hunting party," Walls said, but "that is something that we could perhaps prove with further excavation, giving us a better snapshot of community life."

The Paleo-Inuit people's ability to navigate frigid expanses of open water in kayak-like vessels to reach Kitsissut shows their strong commitment to a maritime lifestyle, the researchers wrote, but it also demonstrates their advanced skills in navigation and watercraft technology.

"Archaeologists have tended to think about the area as a crossroads, or primarily a route of movement between Canada and Greenland," Walls said. But Kitsissut and the polynya are "better framed as a place of innovation."

Archaeology Fragments Quiz: Can you work out what these mysterious artifacts are?

NASA is gearing up for a simulated launch of the Artemis II mega moon rocket tonight after cold weather pushed back the mission's earliest potential lift-off to later this week.

Artemis II and its four-person crew will now leave Earth for the moon as early as Sunday (Feb. 8), two days later than the previous earliest window, according to a statement released by NASA.

The delay stems from a wave of Arctic air that has brought extreme cold to the U.S. in recent weeks. The cold blast has negatively impacted conditions at the Kennedy Space Center in Florida, where the rocket is currently sitting on a launch pad.

"Over the past several days, engineers have been closely monitoring conditions as cold weather and winds move through Florida," a NASA spokesperson wrote in the statement. "Managers have assessed hardware capabilities against the projected forecast given the rare arctic outbreak affecting the state and decided to change the timeline."

NASA needs to get through a simulated launch before the space agency can proceed with an actual launch. The simulated launch is part of a "wet dress rehearsal," during which engineers test fueling the Artemis II rocket. This was originally scheduled for as early as Jan. 31, but NASA is now targeting Monday (Feb. 2), with the simulated launch window beginning at 9 p.m. ET. The space agency said that the test is expected to go on until around 1 a.m. ET (Feb. 3).

Any date that NASA targets for a test or launch is subject to change. The tricky nature of space travel means that delays are often part of the process, so we can expect NASA to postpone the earliest launch window again if weather conditions aren't favorable, or if technical issues emerge. The potential launch windows for Artemis II extend to no later than April 2026.

The Artemis Program is no stranger to delays. Artemis I returned to NASA's Vehicle Assembly Building twice in 2022 following issues during wet dress rehearsals. The uncrewed rocket ultimately took off during NASA's fourth attempt at a launch in November 2022. Artemis II has already been delayed multiple times, in part so that mission engineers can better understand issues that arose during Artemis I.

Artemis II's upcoming mission is the first time in more than 50 years that NASA is sending humans to the moon, and the first time that a woman will be part of the crew. The mission's Orion spacecraft will loop around the moon on a 10-day flight, testing systems ahead of the Artemis III lunar surface mission, which is scheduled for 2028.

NASA wheeled out Artemis II's Space Launch System (SLS) rocket and Orion spacecraft on Jan. 17. With a 212-foot-tall (65 meters) core stage and a total height of 322 feet (98 m) with the Orion crew capsule on top, the structure is taller than the Statue of Liberty.

Engineers have kept Orion powered on with its heaters running during the cold weather, according to NASA. The space agency previously noted that its engineers have been troubleshooting issues in the lead-up to launch. For example, they worked on leaky ground-support hardware that is needed to supply Orion with oxygen.

Once Artemis II clears the wet dress rehearsal and simulated launch stage, NASA will conduct a flight readiness review before committing to a launch date.

NASA intends to send three of its astronauts on Artemis II: Commander Reid Wiseman, pilot Victor Glover and mission specialist Christina Koch, along with Canadian Space Agency astronaut and mission specialist Jeremy Hansen.

The crew has been in quarantine in Houston since Jan. 23. Astronauts go into quarantine ahead of a launch so that they don't pick up any illnesses that could delay their mission. NASA plans to fly the crew to Florida about six days ahead of launch. However, in the statement announcing the delay, NASA said its managers were "assessing the timeline" for the crew's arrival.

NASA hopes that the Artemis Program will lead to a sustained presence on the moon and serve as a stepping stone for sending humans to Mars.

Scientists have identified a tipping point that has amplified El Niño’s effect on sea ice loss in the Arctic.

For years, researchers have known of a feedback loop linking the El Niño-Southern Oscillation (ENSO) and sea ice coverage at high latitudes. But in a new study, researchers found that since around the year 2000, faster transitions between phases of ENSO have a stronger influence on ice loss northeast of Russia. These changes lead to warmer, wetter weather in the region and less sea ice coverage during the fall following the transition.

The results of the new study could help improve predictions of sea ice coverage for ships passing through the region. They could also help scientists better understand the effects of long-term fluctuations in Earth's climate. "Sea ice can make a significant impact on the Arctic climate and maritime safety," study co-author Cen Wang, an atmospheric scientist at The Hong Kong University of Science and Technology, told Live Science.

ENSO is a climate phenomenon involving variations in air pressure and sea surface temperatures in the tropical Pacific over multiple years. These variations can affect climate and weather patterns across the world, including the frequency of hurricanes, tropical cyclones and droughts.

In the new study, published Jan. 14 in the journal Science Advances, researchers explored how ENSO affects Arctic sea ice, focusing specifically on the Laptev and East Siberian seas northeast of Russia. The team combed through monthly data on sea surface temperatures and sea ice concentration that were collected between 1979 and 2023 to find patterns between ENSO transitions and sea ice coverage the following year.

The results showed that shifting out of the El Niño phase forms areas of cold surface waters in the central and eastern Pacific near the tropics during the following fall. After the year 2000, the transitions out of El Niño started to speed up, possibly due to interactions with the Pacific Decadal Oscillation, another long-term climate cycle that affects temperatures in the Pacific Ocean.

Those fast transitions made the cold patches even colder. And those cold areas pushed a high-pressure system known as the Western North Pacific Anticyclone (WNPAC) northward towards the Arctic. Pushing the WNPAC north causes another anticyclone to form above the Laptev and East Siberian seas. Together, these connected processes pull heat and moisture from the north Pacific into the Arctic, melting ice along the way.

Prior to 2000, the connection between the cold areas and the WNPAC wasn't strong enough to affect sea ice coverage in the Arctic, the team found.

The changes that have occurred since 2000 are due to natural cycles in Earth's climate, not human activities, the researchers said. But anthropogenic climate change "is putting a big uncertainty on how we predict those multi-decade ice changes," said Xiaojun Yuan, a physical oceanographer at the Columbia University Lamont-Doherty Earth Observatory who was not involved in the study.

Human-caused climate change could override some of the natural patterns observed in these long-term oscillations, Yuan told Live Science.

In future work, the team will investigate the effects of anthropogenic climate change on sea ice in the region, Wang said.

Part of the Greenland Ice Sheet completely melted about 7,000 years ago at temperatures close to those predicted for the end of this century, and it could have big implications for future sea-level rises, according to a new study.

The Prudhoe Dome, now a 1,640-foot (500-meter) thick ice cap covering 965 square miles (2,500 square kilometers) of northwestern Greenland, melted under the warmer temperatures of the early Holocene, exposing the sediment beneath.

As similar temperatures are predicted by the end of the century, this could lead to significant ice loss over time. The Greenland Ice Sheet, currently the single biggest contributor to sea level rise, would add 24 feet (7.3 meters) to average global sea levels if all its ice were to melt.

"When all you see is ice in all directions, to think of that ice being gone in the recent geological past and again in the future is just really humbling," lead author Caleb Walcott-George, a geologist at the University of Kentucky, said in a statement.

After the end of the last ice age about 11,700 years ago, temperatures at Greenland climbed to higher than current averages, leading to widespread ice melting. But the effects of the changing climate on the extent of the ice sheet are difficult to determine, since much of the evidence that points to ice coverage — or lack thereof — during the Holocene is buried beneath existing ice today.

In the new study, published Monday (Jan. 5) in the journal Nature, scientists drilled through the Prudhoe Dome to collect sediment from beneath the ice sheet. Then, they used infrared light to measure how long the sediments had been buried under the dome without being exposed to sunlight.

The sediment last saw the sun about 7,100 years ago, the team found. That means that the ice must have fully melted at that point in order to expose the dust and rock underneath. Chemical signatures in the ice column suggest that none of the ice was left over from the last ice age, and that the dome fully melted and reformed in the years since.

Summer temperatures were 5.4 to 10.8 degrees Fahrenheit (3 to 6 degrees Celsius) warmer in the Early and Middle Holocene than they are now. Major climate models such as the CMIP6 predict that by 2100, summer temperatures could rise to about the same values. That warming could have a major impact on the Greenland Ice Sheet, the researchers wrote in the study.

But it's not yet clear how long temperatures had to remain that high to fully melt the ice of Prudhoe Dome. Limiting the amount of future warming might help curtail melting at the ice sheet, the researchers wrote.

The early Holocene "is a time known for climate stability, when humans first began developing farming practices and taking steps toward civilization. So for natural, mild climate change of that era to have melted Prudhoe Dome and kept it retreated for potentially thousands of years, it may only be a matter of time before it begins peeling back again from today's human-induced climate change," study co-author author Jason Briner, a geologist and paleoclimatologist at the University at Buffalo, said in the statement.

Additional ice cores taken from elsewhere in Greenland could help map just how far the ice sheet retreated during the Holocene's warmer spell, providing a better insight into how it might respond in the future, and how sea levels might rise as a result. "We have very reliable, numerical models that can predict the rate of melting, but we also want real, observational data points that can tell us indisputably that X amount of warming in the past led to X amount of ice being gone," Briner said.

Study co-author Joerg Schaefer, a research professor at Columbia University’s Lamont-Doherty Earth Observatory, added that the findings will help show which parts of the Greenland Ice Sheet are most vulnerable — which is critical for predicting local sea level rise. "This new science field delivers this information via direct observations and is a game-changer in terms of predicting ice-melt," he said in the statement.

In the Arctic, a major variable for future climate change lives in the ground, invisible.

Microbes in the layers of soil just above the frozen permafrost metabolize carbon, turning it into carbon dioxide and methane, a far more potent greenhouse gas. As these soils warm, more carbon is being unlocked, potentially setting in motion a warming feedback loop sometimes nicknamed the "methane bomb." Now, new research on the microbial denizens of Arctic soils indicates that such a vicious cycle may not be inevitable.

By cataloging the kinds of microbes found in permafrost soils from around the Arctic, as well as in recently thawed permafrost itself, a group of researchers delivered a clearer picture of microbial diversity in Arctic soils, as well as how those microbial communities change as their environment warms up. One key finding in their paper, recently published in Communications Earth and Environment, is that under certain conditions there could be more methane-eating microbes than methane-making microbes in the Arctic, meaning the soil could actually end up being a carbon sink.

"It could be that these systems for a variety of reasons are not actually producing the methane we believe that they're capable of producing," said Jessica Buser-Young, a microbiologist at the University of Alaska Anchorage not affiliated with the research.

The microbes and the methane

Since 2010, a consortium of scientists from Europe has been gathering permafrost samples in the Arctic, digging through topsoil and subsoil and into the permanently frozen ground below. Gathering these samples is difficult in the vast, remote, and frozen northern reaches of the world, but the group retrieved samples from across Canada, Greenland, and Siberia.

In the new paper, the researchers conducted genomic analyses of the microbiome of eight pan-Arctic permafrost and soil samples as well as samples of both intact and degraded permafrost near Fairbanks, Alaska. They focused specifically on microbes, comprising both bacteria and archaea, that either release or consume methane, a greenhouse gas that can be 30 times more potent than carbon dioxide.

When the researchers looked at the data, the first surprise came from the lack of diversity among both methane-producing microbes, or methanogens, and methane-consuming microbes, or methanotrophs, said study coauthor Tim Urich, a microbiologist at the University of Greifswald in Germany.

Among methanotrophs, a single genus, Methylobacter, dominated samples at every location. These bacteria are found across the Arctic, often living in soil layers just above their methanogen counterparts, consuming the methane that bubbles up from below. Why this single genus has been so successful isn't yet known, Urich said.

The analysis "really calls for studying representatives of this specific clade in more detail to understand the ecophysiology and their response to changing conditions in the soil," Urich said.

Possibly defusing the methane bomb

Urich and his coauthors also looked at sites where permafrost had thawed, comparing wet and dry locations. The site with sodden soils held more methanogenic microbes, which thrived in the oxygen-deprived conditions. At dry sites, by contrast, methanotrophic microbes won out, especially a variety with the unique ability to take methane from the air and turn it into less potent carbon dioxide. While these facultative methanotrophs have the ability to metabolize atmospheric methane, researchers noted, they don't necessarily do it in practice.

Regardless, Urich said, the upshot is that a warmer, drier Arctic may be a boon for the changing climate.

"It really depends on the hydrologic fate of these soils," he said.

If the Arctic ends up on the dry end of the spectrum, its soils could become a net sink for methane (though not a large one) as microbes begin sucking gas from the air. The mechanism described by Urich and his colleagues is not the only potential negative methane feedback loop, either. In a recent paper in AGU Advances, Buser-Young and her coauthors found that microbes in Alaska's Copper River Delta that use iron for their metabolism have begun outcompeting those that produce methane, potentially reducing methane emissions.

"We believe that this could be happening potentially everywhere there's glaciers in the world," Buser-Young said.

What studies like Urich's are making clear is that while thawing Arctic permafrost is an obvious sign of climate change, its contribution to warming is less apparent, said Christian Knoblauch, a biogeochemist at the University of Hamburg who was not involved with the research.

"We had so many papers about this methane bomb," he said. "I think this was an oversimplification or an overestimation of methane release."

Future of methane still uncertain

Researchers are still hampered by a paucity of data about the changing Arctic.

High on Urich's list of potentially valuable datasets are studies on the ecophysiology of the methane-associated microbes he and his colleagues found in Arctic soils. Such studies would provide more data on how microbe metabolism changes in response to warming temperatures and varying levels of oxygen, among other things.

Urich also cautioned that his research did not measure levels of methane release or uptake from Arctic soils, leaving unanswered the question of the microbes' actual impact on the environment.

Knoblauch reiterated the need for more data, noting that we still cannot say with certainty whether the future Arctic will be more wet or more dry and therefore what methane release will look like.

"We have a lot of models, and there are a lot of simulations, but we do not have so much data on the ground," he said. "I think the big questions are really how fast is the material decomposed, how much will thaw and in [what] time it is decomposed and then released, and how the system will be affected by changing vegetation."

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

The Arctic Ocean was once an important source of greenhouse gases to the atmosphere — and it could become one again, researchers warn.

Methane (CH₄) is second only to carbon dioxide (CO₂) in trapping heat in Earth's atmosphere. Since 2020, human-driven greenhouse gas emissions have increased atmospheric methane by about 10 parts per billion per year, more than twice as much as CO₂. However, scientists don't yet know how the methane cycle will respond as our planet continues to warm.

In a new study, published Sept. 25 in the journal Nature Geoscience, researchers looked to methane cycling in Earth's past for clues about our future.

The team focused on a period of rapid warming and ocean acidification that occurred around 56 million years ago, known as the Paleocene-Eocene Thermal Maximum (PETM). The PETM is one of the best examples of a major climate shift driven by disruptions in Earth's carbon cycle, much like the global warming we're experiencing today.

Scientists have previously shown that the PETM was accompanied by the widespread release of CO₂ and CH₄ into the oceans and atmosphere, which left distinct geochemical fingerprints in sedimentary rocks from that time. But despite 30 years of research, scientists still can't pinpoint where these gases came from.

To explore how the carbon cycle operated during the PETM, the researchers behind the new study looked at a 50-foot (15 meters) core of marine sediments drilled from the central Arctic Ocean by the Integrated Ocean Drilling Program's Arctic Coring Expedition. The sediments date back to 66 million years, preserving the PETM warming event and the subsequent "recovery" period, during which the climate eventually restabilized.

The team extracted organic molecules from the sediments and measured different forms of carbon within them. They identified the organic molecules, known as biomarkers, to determine what microbes were living on the seafloor when the sediments were deposited. They used the forms of carbon, known as isotopes, to determine what those microbes were eating.

Methane commonly has lighter carbon isotopes than CO₂, meaning methane-munching microbes produce biomarkers with characteristically light carbon isotopes. The researchers tracked these biomarkers in the core samples and found that the dominant methane-eaters in the Arctic Ocean shifted during the PETM.

Prior to the PETM, methane formed deep below the seafloor and was consumed by microbes that breathe sulfate instead of oxygen, via a process known as anaerobic oxidation of methane (AOM). But during the PETM, biomarkers from AOM microbes decreased.

Today, AOM consumes the majority of methane in marine sediments because sulfate is abundant in modern oceans. However, scientists think sulfate was considerably lower during the PETM, meaning these microbes were restricted in how much methane they could eat. The researchers suggest that a massive burp of methane during the PETM could have "overwhelmed the sedimentary AOM biofilter," releasing methane into seawater, they wrote in the study.

Once methane reached the water column, the biomarkers indicated a different set of microbes took over. These microbes consumed methane while breathing oxygen, via a process known as aerobic oxidation of methane (AeOM).

The researchers propose that this switch could have transformed the Arctic into a significant source of CO₂ after the onset of PETM warming. They explained that AOM in the sediments produces the alkaline compound bicarbonate, which helps to buffer the ocean and stabilize its pH. But AeOM in the water column releases CO₂, which contributes to warming and ocean acidification. AeOM microbes also consume O₂, enabling other oxygen-intolerant organisms to spread and gobble up sulfate, which further starves the AOM microbes.

Could a similar Arctic methane switch accelerate climate change today? "We think it is possible and very likely," said study lead author Bumsoo Kim, an organic geochemist at NASA Johnson Space Center. The Arctic Ocean is becoming warmer and fresher, which would consume more oxygen, driving similar changes in the methane cycle, Kim, who was a researcher at Texas A&M University at the time of the study, told Live Science in an email.

However, other scientists are less certain. "The factors that led the Arctic to become a carbon source in the past may not be directly analogous for the future — the Arctic Ocean was physically more restricted from the global ocean and ocean chemistry was different in significant ways," said Sandra Kirtland Turner, associate professor of paleoclimate and paleoceanography at University of California, Riverside, who was not involved in the study.

Kirtland Turner also stressed that the results are a reminder that carbon cycle feedbacks can amplify or extend warming. "Today, carbon cycle feedbacks remain poorly constrained and are rarely even considered past the year 2100," limiting our understanding of their full impacts, she told Live Science.

A potent greenhouse gas has begun seeping out of the Antarctic seafloor in dozens of places, scientists have discovered.

Researchers documented the emergence of these methane seeps in shallow regions of the Ross Sea, a bay off the southern coast of Antarctica. The patches of leaking gas could be caused by global warming, and they could also threaten to accelerate it further, according to a new study published Oct. 1 in the journal Nature Communications.

"Every time we discover or hear of a new one, we feel immediate excitement, but that excitement is quickly replaced with anxiety and concern about what it all means," study lead author Sarah Seabrook, a marine scientist at the research institute Earth Sciences New Zealand, said in a statement.

"If they follow the behaviour of other global seep systems, there is the potential for rapid transfer of methane to the atmosphere from a source that is not currently factored into future climate change scenarios," Seabrook added.

Methane (CH₄) is a greenhouse gas that traps heat in the atmosphere by absorbing outgoing radiation. When methane first enters the atmosphere, it is a lot more effective at trapping heat than carbon dioxide (CO₂), being about 80 times more potent across the first 20 years it's in the atmosphere. This makes methane a particularly aggressive short-term driver of climate change. (CO₂ stays in the atmosphere for longer, so it's a more significant long-term driver.)

About 60% of methane emissions come from human activities such as farming and burning fossil fuels, while the remaining 40% come from natural sources. Scientists are concerned that as the planet gets warmer, more natural methane and carbon dioxide sources, such as those in melting permafrost, are being unlocked, creating a positive feedback loop that accelerates warming even further.

Researchers have previously spotted tens of thousands of methane leaks in the Arctic, but prior to the new study, there was only one confirmed Antarctic methane seep, identified in 2011. Underwater seeps create streams of bubbles as methane and other chemicals dissolve in ocean water following their release from beneath the seabed. White mats of microbial communities live around seeps, making them identifiable on the seafloor.

In the new study, researchers used acoustic surveys, divers and a remotely operated vehicle to explore seeps located between 16 feet (5 meters) and 787 feet (240 m) below the icy surface of the Ross Sea, off the Antarctic mainland. The team initially only went to investigate one seep in Cape Evans, located on the west side of Ross Island, and were surprised to find the seafloor littered with them.

"Last year, we went to Cape Evans to look at one small area where gas bubbles had been discovered and were hoping to find that one site still bubbling," Seabrook said. "Instead, we found dozens more."

The researchers studied areas that have been regularly surveyed for decades, meaning that the seeps must be a new feature. It's not known exactly what is causing the seeps to appear, but the researchers noted that similar processes in the Arctic and paleorecord (past environments) have been attributed to climate-driven cryospheric change — the degradation of Earth's ice that previously locked these chemicals in place.

It's unclear how much methane might be leaving Antarctica and reaching our atmosphere, nor how much remains trapped beneath its thawing ice, but the researchers are concerned that the seeps could be widespread. This raises fears of positive feedback loops as well as a variety of other knock-on effects caused by methane, such as ocean acidification.

Seabrook and her colleagues recommended coordinated, international efforts to urgently study the seeps.

"If these seeps keep emerging at the areas we are working in, it really begs the question of what the shallow coastal environment of Antarctica may look like five or 10 years from now," Seabrook said. "This system is rapidly changing before our eyes from one year to the next."

Microbes that have been suspended in permafrost for up to 40,000 years could "reawaken" and start churning out greenhouse gases if Arctic summers grow much longer, new research suggests.

Under future climate conditions, microbes that have been dormant since the last ice age (2.6 million to 11,700 years ago) may only need a few months to reactivate, according to a study published Sept. 23 in the Journal of Geophysical Research: Geosciences. If they do so for even a part of the year, scientists warn this could trigger a feedback loop that would accelerate permafrost thaw and global warming.

Permafrost is a mix of soil, rocks and ice that has been frozen solid for at least two years straight. A hot spell may thaw the topmost layer of permafrost, known as the active layer, but ancient microbes lurk much deeper down, in layers that thaw only if temperatures rise significantly and for extended periods. For the new study, researchers traveled to Alaska, where permafrost underlies 85% of the land.

"You might have a single hot day in the Alaskan summer, but what matters much more is the lengthening of the summer season to where these warm temperatures extend into the autumn and spring," study lead author Tristan Caro, a postdoctoral research associate in geobiology at Caltech, said in a statement.

Caro and his colleagues collected samples from the Permafrost Research Tunnel near Fairbanks. The tunnel sits 50 feet (15 meters) below ground and extends more than 350 feet (107 m) into the permafrost, offering a glimpse into life during the late Pleistocene epoch (129,000 to 11,700 years ago).

Their aim was to determine resuscitation and growth rates in microbes that lived during this time. But as Caro entered the tunnel, he also noticed mammoth and bison bones protruding from the icy walls, according to the statement.

"The first thing you notice when you walk in there is that it smells really bad," said Caro, who conducted the research as a graduate student at the University of Colorado Boulder. "To a microbiologist, that's very exciting because interesting smells are often microbial."

Back in the lab, the researchers drenched the samples in water containing unusually heavy hydrogen atoms, also known as deuterium. They then incubated the samples in refrigerators set to 25, 39 or 54 degrees Fahrenheit (minus 4, 4 and 12 degrees Celsius) and regularly examined them for changes in microbial activity.

"We wanted to simulate what happens in an Alaskan summer, under future climate conditions where these temperatures reach deeper areas of the permafrost," Caro said.

One month into the experiment, the team didn't note much change, even in the two warmer samples. A handful of microbes had awakened from their long slumber, but only 0.001% to 0.01% of cells were replaced daily by new, active ones.

In the months that followed, however, everything changed. The deuterium in the samples enabled the researchers to track how much water microbes consumed to build the fatty membranes around their cells. This revealed that the ancient organisms preferentially produced fatty acids called glycolipids, which researchers think may be involved in cryopreservation.

Six months into the experiment, the microbes incubated at 39 F and 54 F had undergone "dramatic" changes in community structure and activity levels, according to the study. The samples were less diverse than active layers of permafrost, but the microbes were as active as their more modern counterparts, even producing slimy structures called biofilms that were visible to the naked eye.

"These are not dead samples by any means," Caro said.

The results have implications for the Arctic and Earth's climate more broadly, because microbes in the permafrost survive on organic matter, which they convert into carbon dioxide and methane. Global temperatures are rising faster in the Arctic than anywhere else in the world, thawing the permafrost at alarming rates and for increasing lengths of time. As Arctic summers grow longer and temperatures rise in the deeper layers, colonies of ancient microbes could awaken and start emitting carbon.

Permafrost in northern regions currently holds about twice as much carbon as Earth's atmosphere, so large-scale releases could contribute significantly to climate change. This would accelerate permafrost thaw, triggering a vicious cycle of warming, more thaw and more warming.

"It's one of the biggest unknowns in climate responses," study co-author Sebastian Kopf, an associate professor of geological sciences at the University of Colorado Boulder, said in the statement. "How will the thawing of all this frozen ground, where we know there's tons of carbon stored, affect the ecology of these regions and the rate of climate change?"

But the study only examined ancient microbes from one location, and microbes in other regions may react differently to warming, the researchers noted.

"There's so much permafrost in the world — in Alaska, Siberia and in other northern cold regions," Caro said. "We've only sampled one tiny slice of that."

Scientists have discovered a previously-undetected flood under the Greenland ice sheet that spilled out with such force that it burst through nearly 300 feet (91 meters) of solid ice.

The phenomenon occurred in 2014 and caused 24 billion gallons (90 billion liters) of meltwater to punch out from a subglacial lake under the ice sheet. It is the first time such an event has ever been documented in the country.

By studying the sudden cascade, scientists say they will gain vital information about how ice melts in the region and the destructive impacts of this process on the rest of the Greenland sheet. They published their findings Wednesday (July 30) in the journal Nature Geoscience.

"When we first saw this, because it was so unexpected, we thought there was an issue with our data," study lead author Jade Bowling, a glaciologist at Lancaster University, said in a statement. "However, as we went deeper into our analysis, it became clear that what we were observing was the aftermath of a huge flood of water escaping from underneath the ice."

"The existence of subglacial lakes beneath the Greenland Ice Sheet is still a relatively recent discovery, and — as our study shows — there is still much we don't know about how they evolve and how they can impact on the ice sheet system," Bowling added.

Greenland's ice sheet is one of only two permanent ice sheets on Earth, the other being the Antarctic ice sheet. It is nearly three times the size of Texas, covering roughly 656,000 square miles (1.7 million square kilometers), according to the US National Snow and Ice Data Center (NSIDC) in Colorado, and loses an estimated 33 million tons (30 million metric tons) of ice every hour.

Related: Scientists record never-before-seen 'ice quakes' deep inside Greenland's frozen rivers

Less is known about the role of meltwater from the ice sheet. Scientists previously thought that it flows from the surface to the base then out into the ocean. The new study looked at subglacial lakes — bodies of liquid water trapped beneath the ice — that tend to be fed by meltwater.

The researchers suggest that these lakes could contribute vast amounts of water to the ocean through drainage events but, as they were only recently discovered, they are still poorly understood.

Using satellite data, the team identified a previously-unknown subglacial lake in the north of Greenland, uncovering a huge flood event that fractured the ice from below.

After poring over data collected by a suite of satellites (NASA's ICEsat, ICEsat-2 and Landsat-8, along with the European Space Agency's Sentinel-1, Sentinel-2 and CryoSat-2), the scientists were able to create 3D models of the subglacial flood.

This revealed that, over 10 days between July and August 2014, a 0.77 square-mile (2 square-kilometer) wide, 279 foot (85 m) deep crater was blasted out from the ice sheet as 24 billion gallons of water rushed out to the surface from a meltwater lake uphill. The huge deluge is roughly equivalent to nine hours of Niagara Falls's peak flow.

Further downstream, the scientists discovered that the surge had fractured a large area of ice, leaving uprooted ice blocks that stood at 82 feet (25 m) high and scouring an ice surface around twice the size of New York's Central Park.

The findings not only confound past expectations about how meltwater typically flows through an ice sheet before seeping out into the ocean, but also contradicts models predicting that the sheet is frozen solid at its base.

"What we have found in this study surprised us in many ways,” co-author Amber Leeson, a glaciologist at Lancaster University, said in the statement. “It has taught us new and unexpected things about the way that ice sheets can respond to extreme inputs of surface meltwater, and emphasised the need to better understand the ice sheet's complex hydrological system, both now and in the future."

A mysterious oceanic barrier is stopping some deep-sea jellyfish in the Arctic from reaching the Atlantic Ocean, a new study has found.

The animals, members of the jellyfish subspecies Botrynema brucei ellinorae, inhabit depths between 3,300 and 6,600 feet (1,000 to 2,000 meters) and can be divided into two groups based on whether individual specimens have a knob on their umbrella-like bell structure.

"This jellyfish [...] has two different shapes depending on which area it occurs in — one with a distinctive knob at the top and one without," study lead author Javier Montenegro, a biologist at the University of Western Australia, said in a statement.

The sea creature’s anatomy somehow influences its worldwide distribution: jellyfish with the distinctive knob live across all oceans and latitudes, while those without a knob have only ever been documented in the Arctic and sub-Arctic, Montenegro said.

For the study, Montenegro and his colleagues examined observational and photographic records of B. brucei ellinorae going back more than 120 years. The researchers then mapped the distribution of the jellyfish subspecies by combining these records with genetic analyses. They published their results in the online version of the journal Deep Sea Research on July 3.

Related: Jellyfish Lake: Palau's saltwater pool with a toxic bottom and surface waters brimming with millions of jellyfish

Genetic data indicated that specimens of B. brucei ellinorae with and without knobs in the Arctic and sub-Arctic were almost identical to specimens with knobs in the western Atlantic. This suggested that, despite strong genetic similarities, knobless jellyfish were unable to leave the frigid waters.

So how does the animal’s shape determine its distribution? It appears that access to the Atlantic is blocked by a barrier — not a physical obstacle, but a biological one, or one determined by local geography.

"The differences in shape, despite strong genetic similarities across specimens, above and below 47 degrees north, hint at the existence of an unknown deep-sea bio-geographic barrier in the Atlantic Ocean," Montenegro said.

This barrier is located within the North Atlantic Drift, a warm ocean current that extends northward from the Gulf Stream, but it's unclear if the current itself is the obstacle for knobless jellyfish. A possible explanation could be that there are predators lurking beyond the North Atlantic Drift that knobless jellies aren't equipped to escape — but why having a knob may be advantageous remains unclear.

The barrier "could keep specimens without a knob confined to the north while allowing the free transit of specimens with a knob further south," Montenegro said.

No such barrier is required to keep knobless B. brucei ellinorae in Arctic waters on the Pacific Ocean side, because the Bering Strait already blocks most deep-sea creatures from moving south, according to the study. The strait is only 165 feet (50 m) deep, so deep-sea jellyfish like B. brucei ellinorae can't cross it.

The discovery of a potential oceanic barrier associated with the North Atlantic Drift is important, as it could help scientists better understand evolutionary relationships and dispersal patterns. "The presence of two specimens with distinctive shapes within a single genetic lineage highlights the need to study more about the biodiversity of gelatinous marine animals," Montenegro said.

Birds have been nesting in rugged Arctic environments for almost 73 million years, new research finds — more than 25 million years longer than was previously thought.

A collection of more than 50 fossils found in northern Alaska, which include embryos and hatchlings, suggest some of the early ancestors of modern birds either migrated or adapted to the harsh polar environment in the Mesozoic era, the age of dinosaurs.

"The common conception is they're too primitive to be exhibiting this advanced behavior," Lauren Wilson, lead author of the study and a doctoral student of paleontology at Princeton University, told Live Science. "So you're either dealing with [Arctic winters] as an itty-bitty, freshly hatched bird, or you're 3 months old, and having to fly about 2,000 kilometers [1,240 miles] to get to a point where it makes sense to even migrate," Wilson explained. "I don't think we would expect either of those things from these birds that don't belong to that modern lineage of birds."

Whether the birds migrated south or hunkered down for the winter, the research provides the earliest known evidence of either behavior in birds. And while some modern birds, like the ivory gull (Pagophila eburnea) and snowy owl (Bubo scandiacus) are known to nest in the frigid Arctic, there is now evidence that this behavior started millions of years before the meteor that wiped out non-avian dinosaurs crashed into Earth, if not earlier.

"Many birds nest in the Arctic today, and they are key parts of Arctic communities and ecosystems and food webs," Steve Brusatte, a professor of paleontology and evolution at the University of Edinburgh who peer-reviewed the study but was not involved in it, told Live Science in an email. "These fossils show that birds were already integral parts of these high latitude communities many tens of millions of years ago, and thus that these communities are a long-term norm of Earth history, not a recent ecological innovation of modern times."

The fossils in the collection come from at least three different families of bird: the extinct, loon-like hesperornithes; ichthyornithes, an extinct bird that resembled seagulls; and several species resembling ducks that are within or very similar to neornithes, the group containing all modern birds.

Related: Hoatzin: The strange 'stinkbird' born with clawed wings that appears to be an evolutionary 'orphan'

Notably, the researchers did not find any fossils of the dominant bird group of the Cretaceous period (145 million to 66 million years ago) — enantiornithes, now-extinct birds that typically had teeth in their beaks and claws on their wings. But a few factors reveal why they likely didn't live in the Arctic. They likely took longer than other birds to incubate their eggs, they took several years to reach full adult size (where most modern birds grow to adult size within weeks) and they "may have had a period where they're almost naked because they molted their feathers simultaneously," which is not helpful during an Arctic winter, said study co-author Daniel Ksepka, a paleontologist and curator of the Bruce Museum in Connecticut.

The world was warmer in the Late Cretaceous than it is today, but the region the birds were found in likely experienced freezing temperatures, snow and roughly four straight months of winter darkness. Growing to adulthood so quickly allowed modern birds to practice long-range migration and prosper during those ancient Arctic summers, which boasted around six months of 24-hour daylight and a burst in insect populations.

But the weather wasn't the only challenge. They lived alongside "probably about 12 or 13 different kinds of typical dinosaurs," like the Pachyrhinosaurus, a relative of Triceratops that was about 16 feet (5 meters) long and weighed 2 tons (1,800 kilograms). Other dinosaurs like Troodon, an 11-foot tall meat-eater with short, serrated teeth, "would have happily taken advantage of a bunch of these little cute little chicks for dinner," said Patrick Druckenmiller, director of the University of Alaska Museum of the North and advising author of the study.

To get to the fossil sites in the Prince Creek Formation in Northern Alaska, the researchers drove 500 miles (800 km) from Fairbanks, chartered a small aircraft to fly to the Colville River, then took inflatable motorboats up the river before setting up camp, Druckenmiller said. There they would look for an "orangey, pebbly, sandy" layer of sediment that contains small bones and teeth, and often lay on the permafrost to "excavate with little dental picks and small tools" from the layer itself.

Now that the Prince Creek Formation is "one of the major North American Cretaceous bird sites," according to the researchers, Wilson says the next step is simply to find more fossils.

"The more bones we find, the more confident we can be in exactly what types of birds we have," she said. "We might even still find a random bone that's from a bird we didn't know was there."

Bird quiz: How much do you know about our feathered friends?

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In the dim twilight of an Arctic winter's day, with the low sun stretching its orange fingers across the frozen sea, a group of researchers drill a hole through the ice and insert a hydrogen-powered pump. It looks unremarkable — a piece of pipe protruding from a metal cylinder — but it holds many hopes for protecting this landscape. Soon, it is sucking up seawater from below and spewing it onto the surface, flooding the area with a thin layer of water. Overnight this water will freeze, thickening what's already there.

The hope is that the more robust the ice, the less likely it will be to disappear in the warm summer months.

Since 1979, when satellite records began, Arctic temperatures have risen nearly four times faster than the global average. Sea ice extent has decreased by about 40 percent, and the oldest and thickest ice has declined by a worrying 95 percent. What's more, scientists recently estimated that as temperatures continue to climb, the Arctic's first ice-free day could occur before 2030, in just five years' time.

Related: A long-lost Antarctic ice sheet could predict the future of New York City — one in which Lower Manhattan and Coney Island are 'perpetually submerged'

The researchers are from Real Ice, a United Kingdom-based nonprofit on a mission to preserve this dwindling landscape. Their initial work has shown that pumping just 10 inches of ocean water on top of the ice also boosts growth from the bottom, thickening it by another 20 inches. This is because the flooding process removes the insulating snow layer, enabling more water to freeze. When the process is done, the patch of ice measured up to 80 inches thick — equal to the lower range of older, multi-year ice in the Arctic. "If that is proved to be true on a larger scale, we will show that with relatively little energy we can actually make a big gain through the winter," said Andrea Ceccolini, co-CEO of Real Ice. Ceccolini and Cian Sherwin, his partner CEO, ultimately hope to develop an underwater drone that could swim between locations, detecting the thickness of the ice, pumping up water as necessary, then refueling and moving on to the next spot.

This winter, they carried out their largest field test yet: comparing the impact of eight pumps across nearly half a square mile off the coast of Cambridge Bay, a small town in the Kitikmeot Region of Nunavut, part of the Canadian Arctic. They now wait until June for the results.

Their work is at the heart of a debate about how we mitigate the damage caused by global warming, and whether climate interventions such as this will cause more harm than good.

Loss of sea ice has consequences far beyond the Arctic. Today, the vast white expanse of this ice reflects 80 percent of the sun's energy back into space. Without it, the dark open ocean will absorb this heat, further warming the planet. According to the Scripps Institution of Oceanography at the University of California, San Diego, if our sea ice disappears entirely, it will add the equivalent warming of 25 years of carbon dioxide emissions. There are also huge implications for our weather patterns: Diminishing sea ice is already changing ocean currents, increasing storms, and sending warmer, drier air to California, causing increased wildfires. Within the Arctic, loss of ice means loss of habitat and food security for the animals, microorganisms and Indigenous communities that depend on it.

"Personally, I'm terrified," said Talia Maksagak, executive director of the Kitikmeot Chamber of Commerce, about the changing sea ice. It's freezing later and thinner each year, affecting her community's ability to travel between islands. "People go missing, people are traveling and they fall through the ice," she continues. They also rely on the ice for hunting, fishing, and harvests of wild caribou or musk ox, who migrate across the frozen ocean twice a year — although they, too, are increasingly falling through the thin ice and drowning.

Maksagak has been instrumental in helping Real Ice to consult with the local community about their research, and she is supportive of their work. "If Real Ice comes up with this genius plan to continue the ice freeze longer, I think that would be very beneficial for future generations."

There are still many questions around the feasibility of Real Ice's plan, both for critics and the Real Ice researchers themselves. First, they need to establish if the principle works scientifically — that the ice they've thickened does last longer, counteracting the speed of global warming's impact on the region. At worst, adding salty seawater could potentially cause the ice to melt more quickly in the summer. But results from last year's research suggest not: When testing its pilot ice three months later, Real Ice found its salinity was within normal bounds.

If all goes well with this year's tests, the next step will be an independent environmental risk assessment. Noise is one concern. According to WWF, industrial underwater noise significantly alters the behavior of marine mammals, especially whales. Similarly, blue cod lay their eggs under the ice, algae grows on it, and larger mammals and birds migrate across it. How will they be impacted by Real Ice's water pumps? "These are all questions that we need to ask," said Shaun Fitzgerald, director of the Center for Climate Repair at Cambridge University, which has partnered with Real Ice, "and they all need to be addressed before we can start evaluating whether or not we think this is a good idea."

Fitzgerald predicts four more years of research are needed before the nonprofit can properly recommend the technology. For now, the Nunavut Impact Review Board, Nunavut's environmental assessment agency, has deemed Real Ice's research sites to cause no significant impact.

But critics of the idea argue the process won't scale. "The numbers just don't stack up," said Martin Siegert, a British glaciologist and former co-chair of the Grantham Institute for Climate Change. He pointed to the size of the Arctic — 3.9 million square miles of sea ice on average — and how many pumps would likely be needed to freeze even 10 percent of that. More importantly, who is going to pay for it?

Ceccolini is undaunted by the first question. Their technology is not complicated — "It's technology from 50 years ago, we just need to assemble it in a new way" — and would cost an estimated $5,000 per autonomous pump. Their models predict that 500,000 pumps could rethicken about 386,000 square miles of sea ice each year, or an area half the size of Alaska. Assuming the thicker ice lasts several years, and by targeting different areas annually, Ceccolini estimates the technology could maintain the current summer sea ice levels of around 1.63 million square miles. "We've done much bigger things in humanity, much more complex than this," he said.

As for who pays, that's less clear. One idea is a global fund similar to what's been proposed for tropical rainforests, where if a resource is globally beneficial, like the Amazon or the Arctic, then an international community contributes to its protection. Another idea is "cooling credits," where organizations can pay for a certain amount of ice to be frozen as an offset against global warming. These are a controversial idea started by the California-based, geoengineering start-up Make Sunsets, which believes that stratospheric aerosol injections — releasing reflective particles high into the Earth's atmosphere — is another way to cool the planet. However its research comes with many risks and unknowns that has the scientific community worried, and has even been banned in Mexico. Meanwhile faith in the credits system has been undermined in recent years, with several investigations revealing a lack of integrity in the carbon credits industry.

Panganga Pungowiyi, climate geoengineering organizer for the Indigenous Environmental Network, a nonprofit for environmental and economic justice issues, is vehemently against cooling and carbon credits in principle, explaining that they are "totally against our [Indigenous] value system." She explained that, "it's essentially helping the fossil fuel industry escape accountability and cause harm in other Indigenous communities — more pain, more lung disease, more cancer."

This gets to the heart of the debate — not whether a solution like this can be done, but whether it should be done. Inuit opinion is divided. Whilst Maksagak is supportive of Real Ice, Pungowiyi says the technology doesn't align with Indigenous values, and is concerned about the potential harms of scaling it. In addition to the environmental concerns, Pungowiyi notes that new infrastructure in the Arctic has historically also brought outsiders, often men, and an increase of physical and sexual assault on Indigenous women, many who end up missing or murdered. Ceccolini and Sherwin are aware of such risks and they are clear that any scaling of their technology would be done in partnership with the local community. They hope the project will eventually be Indigenous-run.

"We don't want to repeat the kind of mistakes that have been made by Western researchers and organizations in the past," said Sherwin.

Real Ice is not the only company that wants to protect the Arctic. Arctic Reflections, a Dutch company, is conducting similar ice thickening research in Svalbard; the Arctic Ice Project is assessing if glass beads spread over the ice can increase its reflectivity and protect it from melting; and engineer Hugh Hunt's Marine Cloud Brightening initiative aims to increase the reflectivity of clouds through sprayed particles of sea salt as a way to protect the ice.

"I think these ideas are getting far too much prominence in relation to their credibility and maturity," said Seigert, referring to conversations about Arctic preservation at annual United Nations climate change meetings, known as COP, and the World Economic Forum. It is not only that these technologies are currently unproven, Seigert noted, but that people are already making policy decisions based on their success. It's an argument known as "moral hazard" — the idea that developing climate engineering technologies will reduce people's desire to cut emissions. "This is like a gift to the fossil fuel companies," he said, allowing them to continue using oil, gas and coal without change. "We have the way forward, decarbonization, and we need every effort to make that happen. Any distraction away from that is a problem."

"It's a strong argument," agreed Fitzgerald, of Cambridge University, when asked about moral hazard. "I am concerned about it. It's the one thing that probably does cause me to have sleepless nights. However, we need to look at the lesser of two evils, the risk of not doing this research."

Or, as Sherwin said: "What is the cost of inaction?"

Those in support of climate intervention strategies stress that, although decarbonization is vital, it's moving too slowly, and there is a lack of political will. Technologies like those being developed by Real Ice could buy ourselves more time. Paul Beckwith, a climate system analyst from the University of Ottawa, espouts a three-pronged approach: eliminating fossil fuels, removing carbon dioxide from the atmosphere, and protecting the Arctic.

"It should be less a conversation of one over the other and more how we run all three pillars at the same time," said Sherwin. "Unfortunately we're in a position now where if we don't protect and restore ecosystems, we will face collapse."

This article by Grist is published here as part of the global journalism collaboration Covering Climate Now. This story is part of The 89 Percent Project.

Winter sea ice cover has dropped to its lowest maximum on record as temperatures continue to exceed 2.7 degrees Fahrenheit (1.5 degrees Celsius), new data reveals.

In 2015, world leaders signed the Paris Agreement, an international treaty that promised to limit global warming to preferably below 2.7 F and well below 3.6 F (2 C). Earth is now consistently above that target, with March representing the 20th out of the last 21 months to breach the preferred limit.

Arctic sea ice cover varies throughout the year and usually reaches its maximum extent in March. The European Union's Copernicus Climate Change Service has now shown that the maximum cover for 2025 was the lowest ever. This update echoes a recent NASA report on sea ice cover and highlights a worrying upward trend in global temperatures.

The data shows that sea ice cover was 6% lower than average this year, making it the lowest monthly extent for March in the 47-year history measured by the satellite record. The Climate Change Service also found that March's global temperatures were on average 2.88 F (1.6 C) warmer than preindustrial levels (estimated for between 1850 and 1900), according to a Copernicus statement.

Related: 'Heat is the final boss. Heat is a different beast': The planetary peril no one will be able to avoid

Declining sea ice threatens human and wildlife communities that depend on the ice to survive. The decline also has a variety of adverse environmental impacts and accelerates global warming driven by human activities. This is because liquid water reflects less sunlight than ice, so as sea ice is lost, more of the ocean beneath is exposed and the planet absorbs more heat.

On March 22, NASA and the National Snow and Ice Data Center revealed that Arctic sea ice had reached its maximum extent for 2025. The sea ice cover was 5.53 million square miles (14.33 million square kilometers), around 30,000 square miles (80,000 square km) less than the previous lowest maximum, set in 2017.

The Copernicus update noted that March also marked the fourth consecutive month that cover had been at a record low for the time of year. Sea ice cover and temperature fluctuate from year to year, so climate change doesn't necessarily mean every new month will be a record breaker. And yet Copernicus’ updates have consistently announced record-breaking months.

For global surface air temperature, 2025 had the second-warmest March on record. That means it was warmer than every March on record except for 2024, which was only narrowly warmer.

At the regional level, temperatures were above average over the United States — but not record-breaking — while Europe had the warmest March since records began. Temperatures were above average across Europe and particularly warm over eastern Europe.

Samantha Burgess, the strategic lead for climate at the European Centre for Medium-Range Weather Forecasts, which implements the Copernicus program, said in the statement that "March 2025 was the warmest March for Europe, highlighting once again how temperatures are continuing to break records."

A major disruption to the Arctic polar vortex has bumped the ring of wind that circles the North Pole off its perch and towards Europe, a new animation shows.

The migration could trigger colder-than-average temperatures in parts of the continent and across the eastern U.S. over the coming week, climate scientists say.

The polar vortex started wandering off course March 9, when its high winds suddenly switched from blowing west to east to blowing in the opposite direction. This switch normally happens each year, but it tends to occur in mid-April — meaning this year's reversal struck unusually early, according to a blog post published April 3 by the National Oceanic and Atmospheric Administration (NOAA).

"For much of this winter season, the polar vortex has been strong," NOAA officials wrote in the blog post. "But like a true atmospheric diva, the polar vortex had one last trick up its sleeve, breaking down in a spectacular fashion and bringing some cold air with it."

Related: Bizarre polar vortex over Antarctica delayed ozone hole opening, scientists say

The Arctic polar vortex is a circle of strong, cold winds that picks up every winter over the North Pole. The vortex is always present, but it strengthens in the winter due to a redistribution of heat from the tropics. During the winter, the winds that make up the polar vortex blow from west to east. In spring, as Earth's tilt changes and the North Pole receives more sunlight, the direction of the winds changes to blow from east to west. The winds also become weaker as a result of less heat wafting from the tropics to the pole.

These winds are located in the stratosphere — a layer of the atmosphere that extends between around 6 and 31 miles (10 to 50 kilometers) above Earth's surface.

Occasional "sudden stratospheric warming" events can disrupt the polar vortex. These events happen when large-scale atmospheric waves, called Rossby waves, get pushed into the stratosphere from below, triggering sudden spikes in temperature. Like ocean waves, Rossby waves can "break" on top of the polar vortex, weakening it and — in extreme cases — reversing the direction of its winds.

Last year, a sudden stratospheric warming event hit the polar vortex and reversed its winds in early March, but the vortex recovered. This time, "the vortex does not seem likely to gain a foothold again," NOAA officials wrote.

The switch in wind direction doesn't mean the polar vortex will immediately drop off for the summer, however. The reversed polar vortex has simply "moved off the pole, meandering around over Northern Europe," officials wrote.

NOAA's latest forecasts suggest the polar vortex is unlikely to wander back to its normal position over the North Pole. It probably won't regain its wintertime strength either, officials said, so the likelihood is that it will dissipate and eventually "enter hibernation" over Northern Europe.

As it dissipates, the polar vortex will bring below-average temperatures to Northern Europe, parts of Asia and the eastern U.S., NOAA officials wrote. "Temperatures for the last week of March were pretty normal across the eastern U.S., but the latest forecasts do predict increased chances of below-normal temperatures for the next week," they wrote.

A shift in the polar vortex could bring a blast of Arctic air to millions of Americans in the second half of March, forecasters have warned.

The polar vortex usually keeps cold Arctic air confined above the North Pole, but experts believe it is starting to shift and stretch. That disruption could create the conditions for springtime snow and storms in the central and eastern U.S., according to a statement released by weather website AccuWeather.

"Don't put your winter jacket and gloves away just yet," Paul Pastelok, the lead long-range forecaster at AccuWeather, said in the statement. "Winter is far from over. Many parts of the central and eastern U.S. will see a surge of springlike warmth next week, but the polar vortex could contribute to a sharp drop in temperatures across parts of the U.S. during the week of March 17."

The polar vortex disruption will cause Arctic air to flow south into North America. However, it's not yet clear how severe its impact will be. With the warmer temperatures of spring approaching, any Arctic air flowing into the U.S. won't be as cold compared to if this happened in January, according to the National Oceanic and Atmospheric Administration (NOAA) Polar Vortex Blog.

Related: Spectacular photo taken from ISS shows 'gigantic jet' of upward-shooting lightning towering 50 miles over New Orleans

The polar vortex is an area of low pressure and cold air circulating around the poles in the stratosphere — a layer in the atmosphere hovering between 7.5 and 31 miles (12 and 50 kilometers) above the surface. The Northern Hemisphere's polar vortex regularly expands over winter, sending a blast of cold air south with the jet stream, according to the National Weather Service.

There are a variety of different factors that contribute to cold weather, so not all cold snaps are related to the polar vortex. This winter, the vortex has actually been strong and stable for the most part, with rapid west-to-east winds keeping Arctic air confined to the Arctic. However, a sudden warming will buck that trend.

The temperature difference between the North Pole and the equator maintains the polar vortex's strong west-to-east winds over winter. However, sudden warming in the stratosphere can bring this whirling to a halt and cause the winds to reverse direction. Such a warming event can displace the polar vortex or split it in two, according to the Polar Vortex Blog.

The polar vortex might not recover its strong west-to-east winds after the warming, which would make this the final stratospheric warming event of the season. The polar vortex reversal happens every spring (usually later in mid-April) as sunlight returns to the north pole and the temperature difference between the North Pole and the equator decreases, according to the Polar Vortex Blog.

Last month saw the lowest global sea ice cover for any February on record in a stark reminder of how our planet is warming, new data reveal.

Sea ice is the frozen seawater that floats on the ocean's surface. As the planet warms, the amount of sea ice declines. In February 2025, sea ice around the poles reached an "all-time minimum" when compared with previous Februaries (records began in 1979), according to a statement from the European Union's Copernicus Climate Change Service.

"One of the consequences of a warmer world is melting sea ice, and the record or near-record low sea ice cover at both poles has pushed global sea ice cover to an all-time minimum," Samantha Burgess, the strategic lead for climate at the European Centre for Medium-Range Weather Forecasts, which implements the Copernicus program, said in the statement.

Sea ice loss has the potential to trigger a cascade of adverse environmental impacts, including for the human and wildlife communities living on it. The melting also accelerates global warming even further as the newly exposed ocean beneath reflects less sunlight than bright ice does.

Related: Scientists identify tipping point for Greenland's ice sheet — and it's not far off

Copernicus publishes monthly updates on sea ice cover and global temperatures, so its assessments are based on billions of measurements from satellites, ships, aircraft and weather stations worldwide, according to the statement.

Last month, Copernicus scientists announced that January 2025 was the warmest January on record, even though Earth had entered La Niña, the cold phase of the El Niño climate pattern. The latest report revealed that February 2025 was the third warmest February on record. So it wasn't a record-breaker in that respect, but it did continue a worrying warming trend.

February 2025 was, on average, 2.86 degrees Fahrenheit (1.59 Celsius) warmer than preindustrial levels — the estimated average temperature between 1850 and 1900. World leaders previously promised to limit warming to preferably below 2.7 F (1.5 C) and well below 3.6 F (2 C) in the 2015 Paris Agreement, a legally binding international treaty. However, Earth is now consistently above the 2.7 F target, with February 2025 the 19th month out of the past 20 to breach 2.7 F.

Temperatures fluctuate from year to year, so climate change doesn't mean that every new month is guaranteed to break records. However, there is a clear overall trend of the planet getting warmer and warmer. Last year was the first complete year to breach 2.7 F and ended up as the hottest year on record since preindustrial levels.

Not all parts of the planet get warmer at the same rate. Last month, severe winter storms blasted the U.S. with record-breaking cold, and Copernicus' data revealed that a good chunk of North America was cooler than average for February. However, temperatures were mostly above average around the rest of the world.

Temperatures in the high Arctic were particularly high, with scientists recording "extreme" warming of 36 F (20 C) at the North Pole on Feb. 2, Live Science previously reported. The Arctic is warming around four times faster than the rest of the world — an effect linked to the melting sea ice.

Climate change threatens billions of people worldwide. The effects of global warming include the fueling of wildfires and other extreme weather events that destroy homes; rising sea levels that threaten the survival of coastal communities; and drying agricultural lands that undermine our ability to produce food.

In a first, researchers have recorded countless "ice quakes" that sporadically shake the Greenland Ice Sheet. These quakes may explain the jerky way that the island's frozen rivers move downstream toward the sea, the scientists say.

Researchers detected these quakes by lowering a fiber-optic cable into a 1.7-mile-deep (2.7 kilometers) borehole in the Northeast Greenland Ice Stream — Greenland's largest frozen river that serves as the main artery through which ice is discharged from the ice sheet's interior into the North Atlantic Ocean.

Similar to earthquakes, ice quakes are seismic events that can happen in ice when it fractures and two slabs grind against each other.

Ice quakes in Greenland have gone undetected until now because they are blocked from reaching the surface by a layer of volcanic particles buried 2,950 feet (900 meters) beneath the ice, the researchers said in a statement. These particles originated from a huge eruption of Mount Mazama, in what is now Oregon, about 7,700 years ago, they said.

Related: Greenland's ice sheet — the second biggest in the world — is cracking open at alarming speed, scientists discover

Not only do volcanic particles prevent seismic waves from traveling to the surface, but they may also be directly responsible for the quakes, Andreas Fichtner, a professor of geophysics at the Swiss Federal Institute of Technology (ETH) in Zurich and the lead author of a new study published Feb. 6 in the journal Science, said in the statement. The ice quakes probably start from impurities in the ice, such as sulphates and other particles, which may destabilize the ice and lead to the formation of small cracks.

"We were astonished by this previously unknown relationship between the dynamics of an ice stream and volcanic eruptions," Fichtner said.

Ice quakes can trigger other ice quakes like dominoes, and thereby propagate horizontally over large distances, according to the statement.

Rethinking how ice streams move

Researchers are interested in ice streams — and the role ice quakes play in the way these streams move ice — because they dump large amounts of ice from glaciers into the sea, contributing to sea level rise. Uncertainties about how exactly ice streams transport their load lead to errors in computer models that help scientists assess the future impacts of climate change.

Previously, scientists thought that the ice only flows slowly through these rivers like thick honey. But the new finding, along with previous research, has forced scientists to rethink the way ice moves.

"The assumption that ice streams only flow like viscous honey is no longer tenable," Fichtner said.

Instead, the new data confirm that tiny quakes deep inside the Greenland Ice Sheet cause ice streams to "also move with a constant stick-slip motion," Fichtner said.

The Greenland Ice Sheet is the largest ice sheet in the Northern Hemisphere, covering approximately 80% of Greenland's landmass. Meltwater from the Greenland Ice Sheet is already the biggest global source of sea level rise, accounting for a 0.6-inch (1 centimeter) increase since the 1990s. Scientists estimate there is enough ice locked inside Greenland to raise sea levels by 23 feet (7 m).

"The fact that we've now discovered these ice quakes is a key step towards gaining a better understanding of the deformation of ice streams on small scales," study co-author Olaf Eisen, a professor of glaciology at the Alfred Wegener Institute for Polar and Marine Research in Germany, said in the statement.

Name: Thule snow goggles

What it is: Eye protection carved from walrus ivory

Where it is from: Nunavut, Canada

When it was made: Circa 800 to 1200

Related: Dolní Věstonice Portrait Head: The oldest known human portrait in the world

What it tells us about the past:

These goggles, crafted by the Thule people who lived in Alaska and northern Canada around 800 to 1600, are a very early example of an accessory used to protect the eyes from Arctic snow and ice. In the Inuktitut language, the goggles are known as iggaak.

Carved from walrus ivory, the goggles were made sometime between 800 and 1200. The eyewear measures 5 inches (12.7 centimeters) across and 1.1 inches (2.9 cm) tall, and it may have once had leather or sinew straps to affix it to someone's face. This particular example was collected around 1930 by a Royal Canadian Mounted Police officer on north Baffin Island in the Nunavut territory, according to the Metropolitan Museum of Art in New York City, where the object is on display.

These snow goggles are easily identifiable by the wide and narrow eye slits, which functioned to shield the wearer from eyeball sunburns, as well as from the blowing ice and snow, while allowing a wide field of vision. They have been found throughout the Arctic, suggesting they are highly effective eye protection. This example is decorated with engravings of double lines, spikes and Y shapes, which were likely significant to the wearer.

According to the University of Alaska Museum of the North, the Thule people are considered the ancestors of modern Inuit, and they perfected various Arctic adaptations, including hunting sea mammals, using dogs to pull sleds, and creating snowhouses or igloos. The Thule were proficient at sewing; they used animal skins to make tents and clothing. There is also evidence that the Thule traded with the Norse when they met around Baffin Bay, located between Baffin Island and Greenland.

Iggaak are often considered one of the earliest forms of protective eyewear in the world, dating back at least 1,200 years. Today, however, most Inuit wear contemporary sunglasses with polarized lenses instead of traditional snow goggles.

New satellite images reveal the stark pace of global warming in Alaska, with last year's snow vanishing and leaving behind miles of bare ground.

The images, taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Terra and Aqua satellites, show Bristol Bay Borough in southern Alaska. Anchorage, which is located to the northeast, had an average January snow depth of 13 inches (33 centimeters) between 1998 and 2025.

But this year, the station, alongside other parts of the state, reported next to no snow on the ground. What is left behind are large patches of ground visible from space.

"Since December 2024, temperatures across the state have been 5 to 10 degrees Fahrenheit (3 to 6 degrees Celsius) above normal, according to NOAA, and isolated areas have experienced even greater anomalies," NASA Earth Observatory wrote in a blog post accompanying the new images. "The warm temperatures caused existing snow and ice to melt and new precipitation to fall as rain."

As climate change heats up the planet, Arctic regions such as Alaska are experiencing dramatic rates of warming, with temperatures increasing up to four times faster than the rest of the world. Anchorage's average temperature was 29.3 F (minus 1.5 C) in January — 13 F (7.2 C) above average and warmer than readings taken in three dozen other states.

Related: Alaska's rivers are turning bright orange and as acidic as vinegar as toxic metal escapes from melting permafrost

The reasons for this are twofold. First, unusual weather conditions across the North Pacific fueled a marine heatwave across North America this winter. This warming was worsened in Alaska thanks to a warm, high-pressure ridge of air hanging over the state.

Second, climate change is increasingly chipping away at the region's sea ice, which acts as a protective shield that reflects the sun's rays back into space But this phenomenon, known as the albedo effect, is now working in reverse, with melting sea ice uncovering darker waters that absorb more of the sun's rays.

This means that, as our planet warms, Arctic regions are transforming from planetary refrigerators to radiators. This is causing Alaska's snowpack, the snow that accumulates in winter and melts in spring, to shrink. Climate models predict that by the middle of this century, a dramatic reduction in snow pack will threaten the region's glaciers and bring stronger storms and more rainfall.

At the end of January, the dissipation of the high-pressure front led to a blast of Arctic winds that brought back sub-zero temperatures across the state. Local forecasts don't expect this to last for long, however, with warmer-than-average temperatures predicted to return to the state by mid-February.

Temperatures in the North Pole soared above freezing over the weekend — with the high Arctic reaching 36 degrees Fahrenheit (20 degrees Celsius) above average. Scientists are concerned that these temperatures will melt more sea ice and accelerate Arctic warming.

Temperatures at the North Pole breached 32 F (0 C), the melting point of ice, on Sunday (Feb. 2) after climbing 36 F above the region's daily average temperature recorded between 1991 to 2020, the Guardian reported on Tuesday (Feb. 4).

The European Union's Copernicus Climate Change Service registered warming near the North Pole, while an Arctic snow buoy — a device that measures snow depth and temperature — logged an absolute temperature of 32.9 F (0.5 C).

Mika Rantanen, a weather and climate change impact researcher at the Finnish Meteorological Institute, told the Guardian that it was difficult to estimate the exact temperature change — with remote regions like the central Arctic having fewer direct observation sites — but the models indicated a temperature anomaly of more than 36 F.

"This was a very extreme winter warming event," Rantanen said. "Probably not the most extreme ever observed, but still at the upper edge of what can happen in the Arctic."

Related: Ocean warming 4 times faster than in 1980s — and likely to accelerate in coming decades

The unusually warm weekend was linked to a weather system over Iceland, Julien Nicolas, a senior scientist at the Copernicus Climate Change Service, told the Guardian. He said that a deep low-pressure system was directing a flow of warm air to the North Pole, strengthened by hot seas in the northeastern Atlantic.

"This type of event is relatively rare, but we are not able to assess its frequency without further analysis," Nicolas said.

Warm temperatures have been recorded in the region before. A winter heatwave in 2016 pushed North Pole temperatures to around 32 F on Dec. 24 — about the same as the warming observed over the weekend. And in February 2018, another heatwave caused the North Pole to pass 32 F multiple times, with temperatures peaking at 43 F (6 C), according to the National Oceanic and Atmospheric Administration.

Climate change is particularly noticeable in the Arctic, where temperatures are warming around four times faster than the rest of the world. This accelerated warming, called Arctic amplification, stems from melting sea ice.

Ice reflects more sunlight than land or water, so when climate change melts Arctic sea ice, the region absorbs more sunlight and warms up even faster than non-icy areas, according to the International Science Council.

Above freezing temperatures, like those observed over the weekend, melt ice and therefore accelerate warming in the Arctic that ultimately leads to more ice loss and more warming. Indigenous Peoples and a whole host of wildlife — from polar bears to whales — depend on the sea ice habitat, so as it declines, these human and wildlife communities suffer.

Florida has been hit by record-breaking snowfall as a historic winter storm sweeps through the Deep South and Gulf Coast.

Florida governor Ron DeSantis issued a state of emergency on Monday (Jan. 20) ahead of the massive snowstorm's arrival in the region. By Tuesday, there were widespread reports of 5 to 12 inches (13 to 31 centimeters) of snow around Pensacola, smashing the previous state record of 4 inches (10 cm), Fox Weather reported.

The National Weather Service (NWS) issued a warning on Wednesday (Jan. 22), noting there would be "dangerously cold temperatures" for large parts of the South and eastern U.S. The "potentially historic" storm is expected to bring sub-freezing temperatures that will persist throughout the week, according to a statement from the NWS Weather Prediction Center posted on Facebook.

Much of the U.S. is experiencing deep chills as Arctic air sweeps across the eastern two-thirds of the country. The rare snowfall in Florida is part of what could be the biggest snow and ice storm in more than 100 years for some parts of the Gulf Coast, the weather website AccuWeather reported.

Parts of the country from northern Florida to North Carolina will continue to see heavy snow, sleet and freezing rain as the winter storm persists through Wednesday morning, according to NWS.

Related: 'Unusual' and weak La Niña finally here, NOAA confirms

Forecasters predicted an unusually cold spell was coming at the beginning of the month, with large-scale pressure changes and a shift in the polar vortex pushing an Arctic blast south.

Millions of people have already faced disruptions due to the freak weather. In the south, the storm dumped snow and ice along 1,000 miles (1,600 kilometers) of interstate from central Texas to northern Florida, AccuWeather reported. Four people have died from suspected hypothermia, including two in Texas, one in Wisconsin and one in Georgia, Sky News reported.

Temperatures should slowly return to normal by the end of the week, but major highway and air traffic disruptions will likely persist, even in areas of the Gulf Coast where the snow has stopped, according to NWS.

"These travel impacts may linger for several days given the historic heavy accumulations combined with frigid temperatures, as well as the lack of equipment for clearing roads compared to areas further north more accustomed to this amount of snowfall," NWS representatives wrote.

Dangerously cold weather from the Arctic is forecast to hit the U.S. next week, with potentially record-breaking low temperatures expected in some areas, analysts warn.

The Arctic blast is being driven by large-scale pressure changes and a shift in the polar vortex, according to the weather website Severe Weather Europe. It will bring the coldest air of the season so far to millions of Americans, with dangerous wind chills likely across the southeastern U.S., while much of the Appalachians, Ohio Valley, Mid-Atlantic, Great Lakes and northeastern U.S. could see heavy snowfall and significant travel disruptions, according to the National Weather Service.

Temperatures are expected to drop as low as 30 degrees Fahrenheit (17 degrees Celsius) below the average for this time of year, with the potential for sub-freezing temperatures as far south as the Gulf Coast and Florida Peninsula. It could get so cold in Florida that iguanas fall out of the trees, according to CNN Weather. Iguanas go into a temporary state of paralysis when they get too cold, so they can't hold onto tree branches.

While it's too early for precise temperature forecasts, the weather website AccuWeather reported that this month could be the coldest January in more than a decade. The Arctic weather is expected to last until at least the middle of January.

"The key here is that the Arctic outbreak will involve many days and not just be a quick one-to-three-day event," Paul Pastelok, lead long-range forecaster at AccuWeather, said in the article. "A trainload of Arctic high pressure areas will move southward into the U.S. from the northern Plains to the Southeast states with the pattern."

Related: Bizarre polar vortex over Antarctica delayed ozone hole opening, scientists say

The polar vortex is an area of low pressure and cold air that circulates around the North and South poles. The vortex is present all year, but it strengthens and expands in the winter in the Northern Hemisphere, pushing cold air south with the jet stream, according to the National Weather Service.

This year, two areas of high pressure are sending the cold air from Canada down into the eastern U.S., according to Fox Weather. The weather pattern could produce winter storms with the potential for snow to accumulate in major cities such as New York, Chicago, Boston, Philadelphia and Washington D.C., according to AccuWeather.

Disruptive and damaging weather

The weather pattern could prove disruptive and damaging, with the possibility for power grid damage, heavy snow across the Great Lakes and into the Northeast, and frozen pipes and water damage in poorly insulated or exposed homes in south-central and southeastern states, according to AccuWeather.

Virginia, North Carolina, South Carolina, Georgia, Alabama and Florida could record their coldest January in many years if the Arctic outbreak reaches its full potential.

"In an extreme scenario where the cold lingers past the middle of January, January 2025 could be the coldest since January 2014 in this region, which was 6 F [3.3 C] colder than the historical average," Dan DePodwin, senior director of forecasting operations at AccuWeather, said in the article.

The Arctic Ocean could have its first ice free day as soon as 2027, an alarming new study reveals.

Arctic sea ice has been melting at an unprecedented rate of more than 12% each decade, meaning we are racing towards the day when nearly all of its ice temporarily disappears.

This "ominous milestone for the planet," will most likely happen within nine to 20 years after 2023 regardless of how humans alter their greenhouse gas emissions, according to a new study published Monday (Nov. 3) in the journal Nature Communications. And the most pessimistic projections predict it could happen as soon as three years' time.

"The first ice-free day in the Arctic won't change things dramatically," co-author Alexandra Jahn, a climatologist at the University of Colorado Boulder, said in a statement. "But it will show that we've fundamentally altered one of the defining characteristics of the natural environment in the Arctic Ocean, which is that it is covered by sea ice and snow year-round, through greenhouse gas emissions."

Earth's sea ice is charted each year by the satellite record, which has measured ice fluctuations at both poles since 1979. The world's sea ice plays a crucial role in regulating ocean and air temperatures, maintaining marine habitats and powering ocean currents that transport heat and nutrients around the globe.

Related: 'We were in disbelief': Antarctica is behaving in a way we've never seen before. Can it recover?

The sea ice surface also reflects some of the sun's energy back into space in a process known as the albedo effect. This effect can also work in reverse — with melting sea ice uncovering darker waters that absorb more of the sun's rays. This means that, as our planet warms, the Arctic has transformed from a refrigerator to a radiator, and it's now warming four times faster than the rest of the world.

The rapid heating has had dramatic and marked consequences. The planet's northernmost sea ice extent, which once spanned an average of 2.6 million square miles (6.85 million square kilometers) between 1979 to 1992, has plummeted to 1.65 million square miles (4.28 million km squared) this year.

The continuing decline means that future climate fluctuations are increasingly likely to push the ice beyond the 0.3 million square mile (1 million km squared) limit below which the region is considered "ice free."

By using 11 climate models and running 366 simulations across them, the researchers behind the new study found that this day could come as soon as three to six years.

This prediction was made only in the nine most pessimistic simulations, which assumed the occurrence of a series of unusually warm seasons. But all of the simulations did eventually predict that an ice-free day would inevitably occur, most likely in the 2030s.

"Because the first ice-free day is likely to happen earlier than the first ice-free month, we want to be prepared. It's also important to know what events could lead to the melting of all sea ice in the Arctic Ocean," lead author Céline Heuzé, a climatology researcher at the University of Gothenburg in Sweden, said in the statement.

Despite the bleakness of their findings, the pair's study does nonetheless come with some good news — a drastic cut to carbon dioxide emissions would dramatically forestall the ice free day, and soften the shock caused by the loss of arctic ice on planetary systems.

"Any reductions in emissions would help preserve sea ice," Jahn said.

Scientists working alongside the U.S. Coast Guard have discovered a 1,640-foot-tall (500 meters) structure that looks like an underwater volcano off the coast of Alaska.

The structure may be spewing gas, based on data collected from the water above it, but the scientists still aren't certain. Whether the structure turns out to be a volcano or not, it is 5,250 feet (1,600 m) deep at its shallowest point, meaning it poses no risk to navigation, according to a statement.

Researchers found the previously unknown structure during a three-part mission aboard the U.S. Coast Guard's icebreaker "Healy" to map the ocean floor in the Chukchi and Beaufort seas.

"Although analysis is ongoing, these findings are exciting and offer insight into what may exist beneath the ocean's surface, much of which is unknown in this region," Meghan McGovern, the commanding officer of the National Oceanic and Atmospheric Administration's (NOAA) "Fairweather" ship who took part in the mission, said in the statement.

Related: 'This could be the origin of the Atlantis legend': Mountain that sank beneath the waves discovered off Canary Islands

Scientists discovered the structure during the first leg of Healy's ongoing mission, which is investigating a portion of the Alaskan Arctic Coast Port Access Route Study (Arctic PARS) area along the north coast of Alaska. Arctic PARS is assessing the potential for new shipping routes along the entire U.S. Arctic coast, from Cape Prince of Wales on Alaska's Seward Peninsula to the U.S. border with Canada near Gordon, Alaska.

The second and third legs of the mission will invite early career scientists to conduct various kinds of ocean-based research, including mapping the seabed and sampling water to fill gaps in experts' understanding of these remote areas.

The Healy's datasets won't be released for a few more weeks, and there is currently little to no information available about the new structure to draw conclusions from, said Tim Orr, a volcanologist and research geologist at the Alaska Volcano Observatory who was not involved in the discovery.

"While we are waiting for the data release, our current understanding of the general area where this feature was found is that young volcanoes are not probable in that location," Orr told Live Science in an email. It's possible that the gas detected above the structure was related to processes other than volcanism, such as a deep-buried hydrocarbon reservoir, Orr said.

"There are submarine volcanoes in Alaska, like the emergent volcano Bogoslof, but those are located in areas of known volcanism, unlike the feature reported by the Healy," he added.

A group of school kids and college students discovered that a Russian island in the Arctic has recently vanished after comparing satellite images of the area for an educational project.

Mesyatsev Island was a slab of ice and grit located just off the coast of the larger Eva-Liv Island in Franz Josef Land — a Russian archipelago of more than 190 islands in the Arctic Ocean. The smaller island, which was essentially just an iceberg, used to be an icy cape attached to its larger neighbor, but it likely broke away at some point before 1985, according to a 2019 study published in Geosciences.

In 2010, Mesyatsev Island had a surface area of around 11.8 million square feet (1.1 million square meters) — or the size of around 20 American Football fields. However, when the group of youngsters assessed new satellite photos of the island taken on Aug. 12 this year, they found that the island had an area of just 323,000 square feet (30,000 square m), which was more than 99.7% less than 14 years ago. By Sept. 3, newer images revealed that the island had completely vanished, according to a statement by the Russian Geographical Society that was translated into English. The students were comparing the satellite photos as part of the RISKSAT project run by the Moscow Aviation Institute.

The likely cause of the island's disappearance is rising temperatures caused by human-caused climate change, Alexey Kucheiko, a researcher at the Moscow Aviation Institute who coordinated the RISKSAT project, said in the statement. "The island has completely melted," he said.

Related: Which country has the most islands?

Mesyatsev Island had been melting ever since it broke away from Eva-Liv Island, but the rate at which it disappeared ramped up over the last decade. By 2015, the island measured around 5.7 million square feet (530,000 square meters) — less than half its total in 2010. And by 2022, it had become so small that researchers stopped monitoring it because they thought it would imminently disappear.

It was a surprise, therefore, that what was left of the island was still initially visible in the satellite images first observed by the students in August this year.

Researchers had initially abandoned tracking Mesyatsev Island because of a sharp increase in its rate of melting, which was triggered by a darkening of the island's icy surface in 2021. This darkening was likely the result of a layer of dust that had either blown onto the island or been released from the melting ice. This caused the ice to start absorbing more solar radiation, according to the Russian Geographical Society.

Researchers are unsure why the island has persisted longer than expected. However, experts previously theorized that the island's dusty layer could be removed by waves or rainwater, which could explain why it stopped melting so quickly.

Back when Mesyatsev Island was still attached to Eva-Liv Island, it was an important nesting site for walruses. However, the animals had to find a new place to meet up during the breeding season once the ice mass broke away, Yevgeny Yermolov, head of the historical and cultural heritage preservation department of the Russian Arctic National Park, told the state-run news site TASS.

Experts believe that the former Mesyatsev cape was left behind by a glacier that covered most of Eva-Live Island in the past, potentially when the larger island was still attached to another landmass, Yermolov added.

This 2014 aerial photo shows what looks like an unusually large and deep puddle of vibrant blue meltwater sitting on top of an unnamed Alaskan glacier. Similar melt ponds are becoming more common across the Arctic due to climate change and are further accelerating the rate at which the region is losing its ice.

The striking melt pond, which is littered with hundreds of tiny icebergs, is around 2,300 feet (700 meters) across at its widest point. The pool's vibrant blue color makes it seem like it is exceptionally deep. However, this is likely just an illusion caused by the ice below. On average, Arctic sea ice melt ponds are only around 9 inches (22 centimeters) deep, according to a 2022 study. However, it is unclear exactly how deep this puddle is.

Zoomed-out versions of the photo show that the melt pond was surrounded by nothing but snow for miles. Normally, melt ponds are grouped close together in clusters. It is unclear what caused this pond to grow so large in isolation.

The icy lagoon was spotted by the Multiple Altimeter Beam Experimental Lidar (MABEL) instrument onboard NASA's ER-2 airplane — a special research plane that can fly more than twice as high as commercial jets. The aircraft was sweeping the area as part of a wider survey of Arctic melt ponds, and it captured hundreds of similar photos. But this pond was one of the largest observed, according to NASA's Earth Observatory.

Related: See all the best images of Earth from space

Melt ponds form in late spring and early summer as the ice thaws from the warmth and the resulting water pools in depressions within the ice. These features have always been present in the Arctic. However, they have become much more common in recent years due to the effects of human-caused climate change.

The increased appearance of melt ponds is concerning for researchers because the dark blue puddles absorb much more sunlight than snow and ice do. This causes the ponds to warm up and melt more of the ice around them, especially when they appear on fragile sea ice. This "positive feedback loop" could end up triggering a runaway effect in which the rate of melting exponentially increases.

As a result, the number of melt ponds that appear each summer is a good predictor of a year's Arctic's minimum sea ice extent, or the point at which the surface area of the region's sea ice is lowest, Mongabay recently reported.

However, despite the importance of monitoring these melt ponds, some researchers say we still do not understand them enough to make such predictions.

In a 2023 review article, experts wrote that "limited observations of melt ponds are far from adequate," which is leading to a "lack of spatial and temporal scale-knowledge" about when and where they form. This fosters uncertainty about their role in the climate crisis. However, this problem could be remedied by increasing the amount of aerial observations of the Arctic and using artificial intelligence to help comb through the data, the review authors argue.

Polar bears are developing horrific wounds on their paws due to changing ice conditions in the Arctic, a new study reports.

In the most severe cases, researchers describe two bears with crippling, dinner plate-size balls of ice stuck to their feet. Beneath the ice balls, the bears' paw pads were covered in deep, bleeding cuts.

"I'd never seen that before," study lead author Kristin Laidre, a marine ecologist and associate professor at the University of Washington, said in a statement. "The two most-affected bears couldn't run — they couldn't even walk very easily."

This is the first time scientists observe such injuries in polar bears, according to the study, published Oct. 22 in the journal Ecology.

The debilitating ice balls likely formed due to slushy snow sticking between bumps on the pads that provide the grip polar bears need to walk on slippery surfaces. Snow accumulated on the pads and then froze solid, the researchers suggest, forming blocks of ice measuring 12 inches (30 centimeters) across.

Related: Bleak photo of polar bear with plastic in its jaws in the remote Arctic shows pollution's 'pervasive grip'

"The chunks of ice weren't just caught up in the hair," Laidre said. "They were sealed to the skin, and when you palpated the feet it was apparent that the bears were in pain."

Researchers say roughly one in four polar bears (Ursus maritimus) from two populations in northern Greenland whose feet they examined suffered from ice-related injuries. Affected bears were mostly adult males, which tend to travel longer distances and are much heavier than females or cubs.

Laidre and study co-author Stephen Atkinson, a wildlife biologist and veterinarian, examined polar bears from populations in East Greenland and Kane Basin — a waterway between Greenland and Canada's northernmost island, called Ellesmere Island — between 2012 and 2022. They captured the animals as part of standard population assessments, sedating them before conducting routine health checks.

Thirty-one of 61 bears in the Kane Basin population had laceration, skin ulceration, hair loss or ice buildup on their paws. Between 2012 and 2013, 73% of adult males in this population were affected, according to the study. In the East Greenland population, between 2018 and 2022, 15 of 124 polar bears displayed similar injuries.

The researchers proposed several explanations for the wounds and interviewed Indigenous hunters to identify potential causes. Ice buildup and lacerations may result from rising temperatures in the Arctic, with warm spells leading to wet snow and freeze-thaw cycles that create brittle ice on which polar bears cut their feet, the scientists suggested.

Climate change is leading to more frequent rainfall in the Arctic, turning snow into slush that becomes lodged in polar bears' paws, where it freezes, they wrote in the study. Warmer temperatures also cause the surface snow to melt and then refreeze into a hard crust, which heavy polar bears break when they trample over it, injuring themselves.

Indigenous hunters in Kane Basin knew about the lesions on polar bears' feet and attributed them to increased movement during the mating and hunting season. But the hunters also recognized these injuries as a recent phenomenon. They mentioned that wet snow conditions negatively impact sled dogs, too. According to the study, the hunters noted they now have to trim the hairs between their dogs' pads to prevent ice buildup and lameness.

John Whiteman, an assistant professor of biology at Old Dominion University in Virginia and chief research scientist at the non-profit organization Polar Bears International, said he has never seen or heard about these types of injuries before.

"This report is definitely surprising," Whiteman, who was not involved in the new study, told Live Science in an email. "If the conditions that encourage ice clumps become a common occurrence across a large area, more bears would be at risk for foot damage."

Fool's gold may be driving a disturbing climate feedback loop in the Canadian Arctic.

Erosion of rocks like pyrite, or fool's gold, releases carbon dioxide. And thanks to that weathering, CO2 emissions from Canada's Mackenzie River Basin could double by 2100, a change equivalent to half the current annual emissions from the country's aviation industry, a new study found.

Sulfide minerals like pyrite react with oxygen and other minerals to release sulfate and carbon dioxide. As warming causes more Arctic permafrost to thaw, more rocks are exposed to the atmosphere and weathered, creating a positive feedback loop in emissions. The researchers published their findings Oct. 9 in the journal Science Advances.

"The relationship with temperature appears to be exponential," co-author Robert Hilton, a professor of geology at the University of Oxford, told Live Science. "That means it appears to be accelerating as the region warms."

Scientists still don't know if there are natural brakes on this climate feedback loop, but better understanding how rates of weathering, and carbon dioxide emissions, will change in response to rising temperatures and environmental changes is crucial to predicting future warming.

Related: Greenhouse gas 80 times more potent than CO2 is rising in the atmosphere — and fast

To look for clues, the researchers took records of sulfate concentrations (sulfate, like CO2, is a product of sulfide weathering) and corresponding temperatures from 23 locations across the Mackenzie River Basin, the largest river system in Canada.

They found that sulfate increased rapidly with temperature. Between 1960 and 2020, sulfide weathering increased by 45% as temperatures rose by 2.3 degrees Celsius (4.14 degrees Fahrenheit).

These chemical reactions appear to be occurring at their fastest rates in mountain regions where rocks are broken open by water seeping in and expanding as it freezes, a process known as frost cracking. They are slower in lowland regions where peat forms a protective layer between the rocks and the air, the researchers note.

But the exact extent of the problem is unclear, Hilton said. Sulfide rocks are believed to exist across the Arctic, including the Canadian Rockies, Svalbard and Greenland, but their concentrations remain understudied. Additionally, there could be other environmental factors, such as less permafrost melting or more soil forming, that could slow down this weathering.

"This could be if the landscape stabilizes, and we run out of minerals to react. This could be over 10s to 100s of years, we don't know," Hilton said. "We think the rates are highest where exposed rocks are weathering. This means settings where soil develops could see a slow down, for instance as the Arctic greens. But again, we lack data on the timescales of this response, and we don't see any slow down in our data."

The researchers are also investigating ways to mitigate this process.

"These reactions aren't just happening in the Arctic. They seem to be increasing in other places where rocks have been exposed by deforestation and land use change, for example in the European Alps," Hilton said. "In those locations it may be more feasible to consider solutions which have co-benefits — for example reforestation which could act to lower these rock mineral reactions and CO2 release, while building tree biomass and soil carbon stocks."

And while the weathering feedback loop is an important source of emissions in the region, it's probably a smaller problem than the release of methane and carbon dioxide from thawing permafrost, Hilton said.

"I would say it's important not to be too alarmist about this," Hilton said.

A Japanese scientist has taken inspiration from the climate crisis to compose music that sounds as ominous as current forecasts of ecological breakdown.

Hiroto Nagai, a geoenvironmental scientist and associate professor at Rissho University in Tokyo, compiled publicly available climate data from the Arctic and Antarctic to produce a 6-minute chamber music composition for string quartet. Musicians performed the piece in February 2023, with footage of the recital released on YouTube two months later. Nagai then gathered feedback and described the work that went into the music in a study, which was published online April 18, 2024 in the journal iScience.

The aim of the experiment was to raise awareness of climate change through art. "One of the main insights from the participants is that music, unlike usual graphical representations of scientific data, evokes [an] emotional impression first," Nagai wrote in the study. "It grabs the audiences' attention forcefully, while graphical representations require active and conscious recognition instead."

The climate data used for the composition spans the last 30 years. Nagai extracted records of solar radiation, surface temperature, precipitation and cloud thickness from four weather stations in the Arctic and Antarctica to represent the "energy budget" of Earth's poles.

Related: Creepy 'biotwang' noises coming from the Mariana Trench finally explained after 10 years

The energy budget of a region is the balance between the amount of energy incoming from the sun and the amount of energy that is reflected back into space. Earth's energy budget depends on the albedo effect, which dictates that dark-colored surfaces, such as oceans and forests, reflect less energy back into space than light-colored surfaces. Given that polar regions are covered in snow and ice, they reflect almost all the solar radiation that reaches them.

But climate change is reducing the amount of ice at the poles, throwing Earth's energy budget off kilter. Rising temperatures are causing entire ice shelves to collapse and the extent of sea ice to shrink year-on-year. As ice melts, it exposes darker surfaces that absorb more solar radiation, leading to increased warming and triggering a climate feedback loop.

Nagai used software to convert the data into sheet music. He separated the various datasets into sections labeled A to I, with the shape of the music on the page roughly mirroring the curves of the data. He then made stylistic additions and changes to the music to avoid repetitive sequences.

The process of transforming data into sound is known as sonification. While researchers previously tried this method, the resulting soundscapes didn't sound like conventional music due to a lack of stylistic changes.

"There is a tendency to avoid intentional interventions or edits (i.e., contamination) in the original data," Nagai wrote in the study. "As a result, while the information from the original data are preserved as much as possible, composed musical pieces often contain a monotonous progression and lack any significant dynamics."

Nagai's composition, titled "Polar Energy Budget," includes both data-derived melodies and free arrangements. The choice of a string quartet (two violins, a viola and a cello) was based on the four-voice structure and diversity of playing techniques of these instruments.

"This marks a significant turning point from an era where only scientists handled data to an era where artists can freely use data to create their works," Nagai concluded in the study.

This striking satellite photo shows a quartet of near-identical glaciers perched between mountainous peaks on a barren island in the Canadian Arctic. The elongated ice masses, which are threatened by human-caused climate change, help spark new life in the surrounding "polar desert" and have provided researchers with rare opportunities to study some of the world's hardiest plant species.

The four glaciers — Nukapingwa, Arklio, Perkeo, and Midget (from left to right in the image) — are each around 2 miles (3.2 kilometers) long and around 2,000 feet (600 meters) wide on average. They are located along the northern ridge of the Oobloyah Valley at the heart of Ellesmere Island, the 10th-largest island on Earth and Canada's most northern landmass.

Ellesmere Island is a tricky place for life to thrive. Despite remaining largely ice-free all year round, temperatures range between 37.9 degrees Fahrenheit (3.3 degrees Celsius) in the summer and minus 36 F (minus 38 C) in the winter. The area also receives less than 2.5 inches (6.4 centimeters) of precipitation each year — making it a polar desert, according to NASA's Earth Observatory. As a result, only 144 people live on the island (as of 2021), despite the landmass being around the same size as the U.K..

However, seasonal meltwater from glaciers like those in the image provide areas like the Oobloyah Valley with enough moisture to sustain a sparse covering of resilient vegetation. This provides the base of a food web that supports arctic hares, muskoxen, wolves and polar bears. (The name Ellesmere means "land of muskoxen" in French.)

Related: See all the best images of Earth from space

At the terminal end of each glacier (near the bottom of the satellite image), slim crescents of rough jagged ground, known as moraines, surround the tongues of ice. Moraines are areas of churned-up earth left behind as the glaciers retreat up the valley's ridge, according to the U.S. Geological Survey. These areas are completely devoid of life when they are first freed from the glaciers' immense weight, which makes them the perfect testbed for scientists to study how arctic plants colonize new land.

In a 2013 study, researchers from Japan conducted extensive fieldwork at the moraine surrounding the Arklio glacier (second from right) and found that two plants — Dwarf fireweed (Epilobium latifolium) and a type of creeping willow (Salix arctica) — quickly colonize the space, allowing other species to eventually follow suit.

Unfortunately, human-caused climate change is causing glaciers like these to retreat much faster than normal. A 2018 study that compared satellite photos of more than 1,700 glaciers on Ellesmere Island, found that the ice masses had collectively lost around 6% of their total ice between 1999 and 2015.

While retreating glaciers could provide more space for plants to grow in the short term, the loss of ice will eventually reduce the amount of crucial meltwater that is released into the surrounding polar desert, potentially jeopardizing the entire Ellesmere ecosystem in the long run.

Enormous craters in Siberia's permafrost may finally have a decisive explanation. They form when pressurized water causes cracks to form in the permafrost, triggering a sudden, explosive release of methane gas, scientists say.

The mysterious craters measure 160 feet (50 meters) deep and up to 230 feet (70 m) across, and first appeared on Russia's northern Yamal and Gydan peninsulas in 2014. Chunks of rock and ice strewn across the landscape around the craters indicated they were caused by giant explosions. These strange craters have never been found elsewhere in the Arctic.

Now, new research may finally explain why these explosions only occur in Siberia.

"These are very, very specific conditions that allow for this phenomenon to happen," study co-author Ana Morgado, a doctoral student and chemical engineer at the University of Cambridge in the U.K., said in a statement. "We're talking about a very niche geological space."

Related: Thawing Arctic permafrost could release radioactive, cancer-causing radon

No matter how niche, the explosions could trigger a climate feedback loop leading to huge releases of the powerful greenhouse gas methane.

"This might be a very infrequently occurring phenomenon," Morgado said. "But the amount of methane that's being released could have quite a big impact on global warming."

Over the past decade, researchers have proposed several factors that may contribute to the Siberian craters' formation, linking them to permafrost thaw and to the breakdown of water-methane crystals, called methane hydrates, into methane gas and water.

"We knew that something was causing the methane hydrate layer to decompose," Morgado said.

To figure out how all these factors were connected, the researchers worked through a series of equations and conducted experiments in the lab that mimicked the permafrost. They determined that the explosions are likely caused by high pressure, similar to how a balloon explodes when it's overinflated. Next, they had to figure out what caused that hyper-pressurization.

"It's a bit like detective work," Morgado said.

The new study pinpoints pockets of salty water in the permafrost called cryopegs, which lie directly above methane hydrate. These cryopegs, found only in northern Russia, are the leftovers of prehistoric seas that disappeared during the last ice age as temperatures dropped, locking water in continent-wide ice sheets. Cryopegs stay liquid despite their icy surroundings due to high pressures and salt content.

Because cryopegs are much saltier than the surrounding permafrost, meltwater from thawing surface permafrost travels down into these pockets to equalize the salt concentrations between the two water reservoirs, according to the study, published Sept. 26 in the journal Geophysical Research Letters. This slowly builds pressure inside the cryopegs.

Eventually, the strain becomes so high that cracks form in the permafrost above the cryopegs. This releases the pressure within the permafrost. The methane hydrates immediately below the cryopegs are kept stable by low temperatures and high pressure, so a sudden drop in pressure in these layers may cause methane to split off from the crystals and revert to its gas state, triggering a huge explosion.

These processes likely occur over several decades, which is why explosions resulting in craters are rare, the study authors noted.

Editor's Note: This article was updated Oct. 14, 2024 at 10:00 E.T. to add a map showing the location of Siberia's gas emission craters.

Plants can grow with much less light than previously thought, according to a new study on tiny water-based organisms called microalgae that has been published in Nature Communications. The German-led team of researchers lowered light sensors into Arctic water to a depth of 164 feet (50 metres) to test how low light levels must become before plant life ceases to exist, with incredible results.

They found that plants were able to perform photosynthesis — the process in which their leaves convert sunlight into energy — with very little light indeed. Not only did the microalgae carry out this process at the lowest light levels ever recorded (just 0.04 micromoles of photons m⁻²/s⁻¹), this wasn't very far from what computer simulations predict to be the lowest light possible in any circumstances (0.01 micromoles of photons m⁻²/s⁻¹).

To put this in context, typical light conditions outside on a clear day in Europe are between 1,500-2,000 micromoles of photons m⁻²/s⁻¹ — that's more than 37,000-50,000 times the amount of light required by those Arctic microalgae. It is an amazing discovery that some plants are adapted to survive with so much less light.

This discovery offers several exciting possibilities for the field of plant sciences:

1. Extended growing seasons

Many areas around the world receive too little sunlight because they are far from the equator and endure long winters, or are persistently covered by cloud. The UK is affected by cloud cover, for instance: in 2024 it is on the way to having one of the worst periods of total light hours since the 1900s (only the 1930s and early 1990s were worse).

Now that we know how little light is required for photosynthesis, scientists could develop crops that require much less light to thrive in such places by learning from these Arctic microalgae. By unlocking their genetic potential, many crops could benefit by using plant breeding or biotech approaches to alter them accordingly.

In particular, this could help to eke more out of short growing seasons and increase food production. Even in a relatively southerly place like the UK, breeding plants that can photosynthesise with less light would potentially increase crop yields.

Related: Near-indestructible moss can survive gamma rays and liquid nitrogen

2. Sustainable agriculture

There could be additional benefits for growing plants indoors such as in greenhouses, polytunnels or vertical farms (where crops are grown in vertically stacked layers, such as racks of shelves). These systems sometimes rely on artificial lighting, which is both energy-intensive and costly.

If crops can be engineered to perform photosynthesis at lower light intensities — without compromising things like yield, taste or smell, the energy demand for artificial lighting could be reduced. This would reduce costs, a benefit that could be passed on to customers, and also help cut carbon emissions.

3. Space farming

Perhaps one of the most exciting prospects of this research is that it could potentially make it easier to grow plants in space. One of the main challenges for space missions to the Moon, Mars or eventually beyond, is how to feed anyone trying to live in those worlds for any length of time. Sunlight can be limited, so we'll need highly efficient ways of producing food that don't use much energy.

The discovery that photosynthesis can occur under such minimal light conditions suggests that crops could be grown either on other worlds or in spaceships using less energy to create light than previously thought. Combined with crops that are conducive to space conditions — spinach, lettuce and potatoes are among those that have been grown there before — this could be a critical step forward for long-term missions.

In short, this discovery is a promising breakthrough for the future. For those who sat through photosynthesis lessons in school and perhaps found it tedious, these new possibilities move it to a whole other galaxy.

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

This 2012 satellite image captured an unusual snow-topped structure located among a sea of dirty, fracturing sea ice in northern Canada. The curved white hook resembles the rounded, arrowhead-shape badges pinned to the uniforms of fictional Starfleet officers, such as James T. Kirk and Jean-Luc Picard, in the iconic "Star Trek" franchise.

The satellite spotted the quirky feature in Foxe Basin — a shallow, 316,000-square-mile (819,000 square kilometers) body of water north of Hudson Bay. The structure is draped around a group of tiny, rocky islands, known as the Manning Islands.

The icy arrowhead "was probably caused by snow getting trapped in rough, ridged ice that formed as it ran up against the Manning Islands," Nathan Kurtz, chief scientist of the Cryospheric Sciences Laboratory at NASA Goddard Space Flight Center, told NASA's Earth Observatory in 2014. The 1.5-mile-wide (2.5 km) patch appeared to be multi-year sea ice, meaning it was made up of ice dating back several years, he added.

During the summer, when this photo was taken, Arctic sea ice begins to melt and break apart into thousands of smaller fragments that eventually break away and melt completely. In this case, a majority of those fragments had a muddy brown color, which was a result of staining from sediment that got dragged up from the seafloor, according to Earth Observatory.

Related: See all the best images of Earth from space

Some of the larger fragments of ice in the photo are peppered with small blue dots. These are melt ponds, which are shallow puddles of water that form on the surface of the ice as it melts.

The waters surrounding these sea ice fragments are rich in phytoplankton, which makes them a hotspot for a wide variety of marine animals including Arctic terns (Sterna paradisaea), seals, walruses (Odobenus rosmarus), polar bears (Ursus maritimus), narwhals (Monodon monoceros) and beluga whales (Delphinapterus leucas).

This photo was taken during a record-low year for Arctic sea ice. In 2012, the minimum sea ice extent — the lowest amount of sea ice coverage in a given year — was the lowest since records began in 1979, the National Snow and Ice Data Center (NSIDC) reported at the time.

By Aug. 2 that year, which was around seven days after the photo was taken, there was "very little ice left" in Foxe Basin, NASA representatives wrote.

The 2012 record still stands to this day. However, recent years have also seen very low minimum sea ice extent thanks to the increasing effects of human-caused climate change.

This is not the first time that eagle-eyed science-fiction enthusiasts have spotted the Starfleet badge in satellite photos of our solar system.

In 2019, researchers spotted the shape on the surface of Mars in photos from NASA's Mars Reconnaissance Orbiter. In this case, the arrowhead shape was likely the result of strong winds sculpting the Red Planet's rocks.

Scientists were shocked when they discovered a large, ghostly figure that suddenly appeared in satellite images of Greenland 13 years ago. The icy apparition was created by a depression in the snow-covered surface, which formed when an underground lake located directly beneath the figure collapsed.

The blobby specter, which looked like a shapeless figure waving up at space, was spotted in the Flade Isblink ice cap — a roughly 3,300-square-mile (8,550 square kilometers) ice cap sitting on Greenland's northernmost coastline, deep within the Arctic Circle. The icy hole was around 2 miles (3 kilometers) long and just over 1 mile (2 km) across its widest point, and was 230 feet (70 meters) deep when it first appeared, according to NASA's Earth Observatory.

The spooky structure, which researchers also referred to as "the mitten" due to its glove-like shape, formed at some point between Aug. 16 and Sept. 6, 2011, when the area was obscured by cloud cover in satellite photos.

In a 2015 paper, researchers revealed that the depression appeared when a subglacial lake rapidly drained of water, leaving behind an underground cavern that swiftly collapsed. At the peak of this draining event, scientists estimated that 7,600 cubic feet (215 cubic meters) of water escaped the lake every second.

This event was "perhaps the first recorded instance of a rapid drainage of a subglacial lake in Greenland," Kelly Brunt, a glaciologist at NASA's Cryospheric Sciences Laboratory who was not involved in the study, told NASA's Earth Observatory in 2015. The majority of similar submerged lakes in the country are considered to be very stable, she added.

Related: See all the best images of Earth from space

Researchers continued to monitor the depression, and in 2022, a follow-up study revealed that the subglacial lake had been slowly refilling since 2012. By 2021, the floor of the depression had risen by 180 feet (55 m) — rising to 50 feet (15 m) below the surrounding ice — despite a second, smaller draining event in 2019.

Researchers initially believed the majority of the water that reentered the lake came from surface meltwater that trickled down below the ground. However, calculations later revealed that meltwater could only account for 65% of the water in the lake, meaning some other unknown source of water was also at work.

It is still unclear why the subglacial lake drained so quickly in 2011. However, researchers suspect that human-caused climate change may have played a role.

Several subglacial lakes in Antarctica have also undergone similar collapses in recent years, and scientists fear that the escaping water could further accelerate ice loss in some areas.

The "gateway to the underworld" is a colossal, expanding crater in Siberia's permafrost. It is officially called the Batagay (also spelled Batagaika) crater or megaslump and formed when a portion of hillside in the Yana Uplands collapsed in the 1970s. However, the crater wasn't discovered until 1991, when satellite images revealed a rounded cliff face towering over a huge depression in the frigid landscape.

The Batagay crater is the largest megaslump in the world, measuring 3,250 feet (990 meters) wide as of 2023. The cliff face at the top of the formation, or headwall, stands 180 feet (55 m) high.

Related: Methane 'kitchens' in Siberia's permafrost form mounds that can erupt, creating giant craters

When it opened, the gateway exposed layers of permafrost that had been frozen for up to 650,000 years — the oldest permafrost in Siberia and the second-oldest in the world, after relict ground ice in Canada's Yukon Territory that is about 740,000 years old. Recently, researchers found that the gateway is expanding annually by about 35 million cubic feet (1 million cubic meters), with the depression sinking further into the ground and exposing new layers of ancient permafrost.

The headwall of the gateway is also retreating at a rate of 40 feet (12 m) per year due to permafrost thaw, discharging massive amounts of ice and sediment into the crater, according to a 2024 study. Some of this melt material may remain in the crater, but sediment and ice also washes into the Batagay River valley at the far end of the gateway, researchers noted in the study.

The permafrost in this region is 80% ice, which is likely why the hillside slumped in the first place, Thomas Opel, a paleoclimatologist at the Alfred Wegener Institute in Germany who has studied the gateway to the underworld, previously told Live Science.

The gateway sits in a landscape of larch and birch woodlands that became the target of deforestation from the 1940s onward. Deforestation caused the topsoil to rapidly erode and expose the underlying permafrost, which — due to its icy composition — melted more quickly than if it had been richer in sediments. Significant melting during the following decades caused the hillside to disintegrate and collapse, Opel said.

Frozen soils exposed along the gateway's headwall are helping researchers piece together past climates. There are very few ancient permafrost layers in Siberia that are accessible for scientists, so the Batagay megaslump is an important laboratory for paleoclimate research teams, Opel said.

The gateway also offers scientists a glimpse into ancient animal and plant life. For example, in 2018, researchers found an intact, 42,000-year-old Pleistocene horse (Equus caballus lenensis) foal sticking out of the megaslump's headwall. Older permafrost layers may not contain such well-preserved specimens, Opel said, but there's probably ancient DNA to be found.

"There is certainly more to come," Opel said.

Discover more incredible places, where we highlight the fantastic history and science behind some of the most dramatic landscapes on Earth.

Scientists have finally identified the cause of a mysterious seismic signal that shook Earth for nine consecutive days last year. It turns out that our planet was rocked by a mega tsunami trapped inside a fjord after a mountaintop collapse.

The gigantic wave, measuring 650 feet (200 meters) high, sloshed back and forth inside East Greenland's Dickson Fjord for nine days in September 2023, its movement sending seismic waves reverberating through the planet's crust.

Scientists were initially baffled by the signal. But an investigation using satellite and ground imagery eventually tracked the cause of the seismic activity to the mountain, which was destabilized by climate change melting the glacier at its base. The researchers published their findings today (Sept. 12) in the journal Science.

"When we set out on this scientific adventure, everybody was puzzled and no one had the faintest idea what caused this signal," study lead author Kristian Svennevig, a geologist at the Geological Survey of Denmark and Greenland (GEUS), said in a statement. "All we knew was that it was somehow associated with the landslide. We only managed to solve this enigma through a huge interdisciplinary and international effort."

After being picked up by seismic monitoring stations in September, two aspects of the signal puzzled scientists. Firstly, unlike higher-frequency earthquakes, it was oscillating with a 92-second interval between peaks. And secondly, it was doing this for days on end.

Scientists soon tied the possible cause to a landslide in the fjord, but to understand how it produced the signal, the scientists combined field measurements, satellite imagery and supercomputer models to reconstruct what happened.

Related: When was the last time Antarctica was ice-free?

Their investigation revealed that a massive landslide most likely caused a tsunami wave to rock back and forth across the narrow fjord — a phenomenon known as a seiche.

"It was a big challenge to do an accurate computer simulation of such a long-lasting, sloshing tsunami," study co-author Alice Gabriel, a seismologist at the University of California, San Diego, said in the statement.

The landslide that caused the giant tsunami was the result of climate change, the researchers said. Climate change is melting the ice around the poles at an accelerating rate, and in the fjord's case it dislodged 33 million cubic yards (25 million cubic meters) of rock and ice — roughly the equivalent of 10,000 Olympic-size swimming pools — and sent it crashing into the sea.

No one was harmed by the collapse, but the wave did destroy $200,000 of infrastructure at an unoccupied research station on nearby Ella Island. The researchers say that the worsening effects of climate change could cause more destructive landslides around polar regions.

"Climate change is shifting what is typical on Earth, and it can set unusual events into motion," Gabriel said.

The researchers hope that their discovery of the seismic signal's origins will inspire others to look through the seismic record for similar events, which could help them identify the exact conditions that lead to potentially devastating polar landslides.

"This shows there is stuff out there that we still don't understand and haven't seen before," study co-author Carl Ebeling, a geophysicist at the University of California, San Diego, said in the statement. "The essence of science is trying to answer a question we don't know the answer to — that's why this was so exciting to work on."

Mysterious "frost mounds" dotted across Siberia sometimes burst to form giant craters — and now, scientists have taken a step closer to discovering what makes these strange humps pop.

Frost mounds are areas of the permafrost that bulge as fluids accumulate beneath the surface. According to ongoing research at the Siberian Branch of the Russian Academy of Sciences (SBRAS), two distinct "systems" can lead to this bulging: open and closed. In an open system, water and gas pooling beneath the permafrost move around and leak to the surface through cracks. But in a closed system, water and gas are trapped in a pocket that inflates, putting increasing pressure on the permafrost.

The open system is similar to an idea researchers put forward earlier this year. In a preprint review published Jan. 12 to the EarthArXiv database, the scientists argued that natural gas moving between the bedrock and overlying permafrost leads to melting from below. This melting creates pockets in the permafrost where fluids can accumulate, but these are not completely sealed off from the gas beneath or from the surface. The pockets grow as more gas flows into them, leading to more melting and a rise in pressure, which causes the ground to swell.

The gas is mostly thermogenic methane, which likely forms continuously as a by-product when organic matter heats up. "We call it a kitchen [down there], because it's kind of like cooking, and it's creating gas," Helge Hellevang, a professor of environmental geosciences at the University of Oslo in Norway and lead author of the preprint review, told Live Science.

In a closed system, gas and water come from deep within the bedrock. The fluids rise and form a pocket inside the permafrost that is "surrounded by frozen rocks on all sides," according to SBRAS researchers, and therefore does not leak out.

Related: Underwater robot in Siberia's Lake Baikal reveals hidden mud volcanoes — and an active fault

Despite the distinction between open and closed systems, there is nothing to stop one from morphing into the other as the permafrost evolves, Hellevang said. An open system may even need to become closed before it can form a crater, he said.

Scientists still aren't sure exactly how gas accumulates to form frost mounds, but they know the mounds can rupture spontaneously and open up huge holes in the permafrost. The Yamal crater, measuring about 65 feet (20 meters) wide and 165 feet (50 m) deep, is one example. A helicopter pilot spotted the crater 26 miles (42 kilometers) from the Bovanenkovo gas field on Russia's northern Yamal Peninsula in 2014. Since then, scientists have documented seven more of these giant craters across the Yamal and neighboring Gydan peninsulas.

Researchers with SBRAS said frost mounds "explode" to form the craters, but Hellevang disagrees. Explosions require a source of ignition, such as high heat or electricity, but "it's very hard to ignite the gas at sub-zero," he said. "It's more like an eruption than an explosion."

It's possible open systems could create the pressure necessary for an eruption, but that would require very low gas flow rates out of the system, Hellevang said. Closed systems are more likely to trigger eruptions, as they have a bigger buildup of pressure right away, he said.

Both systems may have a heightened risk of eruption as temperatures rise and thaw the permafrost, Hellevang said. "Climate change is weakening the surface through thawing from the top," he said. At some point, the permafrost becomes so thin it cannot withstand the pressure from pockets of gas below, which could spark eruptions.

Sudden gas eruptions pose a risk to people that live on the Yamal and Gydan peninsulas and to infrastructure like gas pipelines. Another big concern, Hellevang said, is that "if the permafrost is a lid for all this massive amount of methane … then these craters might also in the future be pathways for more methane leakages." And that could trigger even more warming, he said.

"Dragon's Eye" is a natural hollow in the rocks along Norway's northwestern coastline that looks just like a reptilian oculus. A boulder that sits at the bottom of the hollow stands out against a bed of white sand and algae, forming the eye's pupil.

"The Dragon Eye is a natural feature that very likely formed beneath the large Fennoscandian Ice Sheet, possibly during the last ice age," Francis Chantel Nixon, an associate professor of physical geography and quaternary geology at the Norwegian University of Science and Technology, told Live Science in an email. "This specific type of glacial landform is called a pothole."

Related: Why does Norway have so many fjords?

The Fennoscandian Ice Sheet was an enormous glacier that blanketed Scandinavia, as well as parts of Northern Europe and northwestern Russia, during the last glacial maximum, around 20,000 years ago. Glaciation can lead to all kinds of geological formations, including features called plastic forms, or p-forms, which result from erosion of the bedrock beneath the ice sheet, Nixon said.

"P-forms are created by meltwater full of abrasive sediments," Nixon said. These sediments include rocks of all shapes and sizes, ranging from fine sand to giant boulders. High-pressure meltwater currents moving beneath the ice may "sculpt the bedrock into smooth-walled depressions, which can be straight, curving or circular, and on the order of centimeters to several meters in width and depth," Nixon said.

Potholes like Dragon's Eye are a type of p-form thought to be shaped by particularly turbulent meltwater currents that concentrate abrasion and erosion in circular patterns. "When the meltwater eventually slows down or disappears, the coarse sediments will settle out of suspension and become trapped inside the pothole," Nixon said, adding that this might be how a boulder came to sit at the bottom of Dragon's Eye.

Dragon's Eye probably emerged from beneath the ice around 16,000 years ago, when deglaciation occurred in the surrounding region, Nixon said. The retreat of the Fennoscandian Ice Sheet exposed the bedrock and its potholes, which are made of gneiss, a type of metamorphic rock with colorful mineral bands that add to the fantastical appearance of the eye.

The eye, which measures roughly 5 feet (1.5 meters) across, looks different depending on the time of day and the tides. At high tide, waves wash over the rocks, episodically depositing and removing sand from the hollow, so that the boulder sometimes sits on bare bedrock. The algae inside the eye also looks different depending on the time of year and the light.

Discover more incredible places, where we highlight the fantastic history and science behind some of the most dramatic landscapes on Earth.

The fate of the Gulf Stream will be decided by a "tug-of-war" between two types of melting from the Greenland Ice Sheet, a new study suggests. 

Throughout the last ice age, between 16,800 to 60,000 years ago, fleets of icebergs launched from the coast of North America, causing vital ocean currents to weaken dramatically.

Now, researchers have found that, despite the present-day calving rates of icebergs from the Greenland Ice Sheet being as high as they were during some of these past events, runoff from Greenland's coasts may halt this disruption. The researchers published their findings May 30 in the journal Science. 

"There's a tug-of-war between the more effective but decelerating ice discharge and less effective accelerating runoff," lead author Yuxin Zhou, a postdoctoral researcher at the University of California, Santa Barbara, told Live Science. "Those are the two influences that we're primarily worried about." 

The Atlantic Meridional Overturning Circulation (AMOC), which includes the Gulf Stream, governs the climate by bringing nutrients, oxygen and heat in tropical waters north and cold water south. The current can exist in two stable states: a stronger, faster one that we rely on today, and another that is much slower and weaker. 

Climate change is slowing this flow by sending fresh water from Greenland's melting ice sheet to make the water less dense and less salty. This has led to a growing number of studies suggesting that the current is slowing and could even be veering toward collapse. 

The discharge of icebergs from the Laurentide Ice Sheet — which covered most of North America during the last Ice Age — are known as Heinrich events. The present-day cause of this melt is climate change, but during the last glacial maximum it likely resulted from a mixture of ocean heating and the weight of ice accumulating on the sheet. 

This led icebergs to slide into the sea and fresh water to cascade from the shelf, both of which caused the AMOC to weaken dramatically over a few hundred years.

To assess whether icebergs calving from Greenland could trigger a collapse of the AMOC in the present day, Zhou and his colleagues studied sediment layers deposited by past Heinrich events. The researchers focused on thorium-230, a form of the radioactive element produced in seawater at a steady rate. This means its concentrations are detectably diluted by fresh meltwater from icebergs. 

Related: The Gulf Stream stopped pumping nutrients during the last ice age — and the same could be happening now

By comparing their results with predicted ice outflow from Greenland, the researchers found that modern-day climate change (taken since the Industrial Revolution) was comparable to a "midrange" Heinrich event. 

But there are key differences between then and now. During the last ice age, the slowdown of the AMOC had started before icebergs started calving. And, despite having more variability than previously thought, the AMOC is currently in a "pretty healthy state" without significant slowdown, Zhou said.

Zhou said that the changes we're seeing today are governed by the relationship between iceberg calving and freshwater melt straight from the shelf. Icebergs are the most significant factor in this slowdown, while runoff plays a secondary role. But while melt does cause some slowdown, it also slows iceberg production, creating the tug-of-war whose interplay will decide the AMOC's future.

But if the AMOC is taken to be starting today from a stronger position than it did in ancient times, that could be a reason for cautious optimism, Zhou said.

"It's going to become more and more clear in the future as more studies come out," Zhou said. "But I do think, in the near term before 2100, our study says that the AMOC is probably not going to be severely weakened."

However, the researchers noted that their study does not factor in other effects from the warming of the ocean and the Arctic. This means other climate scientists have cautioned against uncritically applying the research's assumptions to the present day.

"A big issue is that how the AMOC behaved (and responded to meltwater) during the last Ice Age is likely to be very different to today," David Thornalley, a professor of ocean and climate science at University College London, told Live Science. "The ocean-atmosphere climate system behaves differently if you have massive ice sheets in North America and meltwater is entering the ocean in different places." 

These differences, when paired with recent studies that suggest AMOC has already weakened and may even be approaching a tipping point, could prove crucial, Thornalley said.

"There is loads we still need to work out to be confident about future AMOC behavior: how good our models are; how easily the modern AMOC can be destabilized; [and] there might be unexpected surprises, good or bad," Thornalley said. "But there are enough reasons to be concerned about the AMOC, and we should apply the precautionary principle — we really don't want to see firsthand the climate impacts of an AMOC collapse. It is just one of many climate impacts we should do all we can to avoid."

This stunning satellite image shows a trio of barren islands in the Russian Arctic, offering a rare glimpse at the colorful, concentric rings of the region's ever-present ice caps.

The Severnaya Zemlya archipelago is a collection of Russian-owned islands in the Arctic Ocean that cover around 14,300 square miles (37,000 square kilometers) — around the same size as Maryland — beyond Siberia's northernmost coastline. The archipelago sits along the boundary between the Kara Sea and the Laptev Sea and has four main landmasses: Komsomolets Island, Pioneer Island, October Revolution Island and Bolshevik Island.

The region was only discovered in 1913 and was not properly visited until a couple decades later, making it one of the last of Earth's major archipelagos to be properly mapped, according to Encyclopedia Britannica.

This photo shows the intersection between Komsomolets Island (center), Pioneer Island (left) and October Revolution Island (right), which are separated by just a few miles of ocean, according to NASA's Earth Observatory.

For most of the year, these islands are largely covered by ice and snow and are connected to one another by thick sea ice. But for around two months every summer, temperatures creep above freezing, enabling some of the frozen water to melt away, which exposes the barren landscape beneath. The only things that live there are lichens and a few bushes.

The thickest and oldest ice remains during the summer months, in the form of glaciers and hill-shaped ice caps that cover around half of the archipelago's surface.

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The ice caps, which can reach up to 820 feet (250 meters) tall, are made up of multi-year ice, meaning that additional layers of snow are compacted into their icy summits every winter while they also lose ice to the summer melt. When viewed from above, this cycle of melting and refreezing creates the stunning concentric rings of color seen in this image, according to NASA's Earth Observatory.

The Severnaya Zemlya archipelago is also home to Russia's largest glacier, the Academy of Sciences Glacier, which is located to the north of the photographed ice cap on Komsomolets Island. This gigantic ice mass covers roughly 2,150 square miles (5,570 square km), which is around two-thirds of the island's surface.

However, the archipelago's year-round ice is slowly disappearing thanks to human-caused climate change. A 2023 study revealed that between 1965 and 2021, the region's glaciers shrank by around 5%, with a similar reduction predicted for the surrounding ice caps.

This rate of ice loss will likely increase in the future as projected warming takes us past irreversible tipping points.

The "gateway to the underworld," a huge crater in Siberia's permafrost, is growing  by 35 million cubic feet (1 million cubic meters) every year as the frozen ground melts, according to a new study.

The crater, officially known as the Batagay (also spelled Batagaika) crater or megaslump, features a rounded cliff face that was first spotted on satellite images in 1991 after a section of hillside collapsed in the Yana Uplands of northern Yakutia in Russia. This collapse exposed layers of permafrost within the remaining portion of the hillside that have been frozen for up to 650,000 years — the oldest permafrost in Siberia and second oldest in the world.

New research suggests that the Batagay megaslump's cliff face, or headwall, is retreating at a rate of 40 feet (12 meters) per year due to permafrost thaw. The collapsed section of the hillside, which fell to 180 feet (55 m) below the headwall, is also melting rapidly and sinking as a result.

"Rapid permafrost thaw features are widespread and observed to increase in Arctic and sub-Arctic ice-rich permafrost terrain," the research team wrote in a study, published online March 31 in the journal Geomorphology. However, the amount of ice and sediment lost from the Batagay megaslump is "exceptionally high" due to the sheer size of the depression, which stretched 3,250 feet (990 m) wide as of 2023.

Related: Thawing Arctic permafrost could release radioactive, cancer-causing radon

The megaslump measured 2,600 feet (790 m) wide in 2014, meaning it grew 660 feet (200 m) wider in less than 10 years. Researchers already knew it was growing, but this is the first time they have quantified the volume of melt gushing out of the crater. They did so by inspecting satellite images, field measurements and data from laboratory testing on samples from Batagay. 

The results indicated that a region of ice and sediment equivalent to more than 14 Great Pyramids of Giza has melted off the megaslump since it collapsed. The rate of melting has remained relatively steady over the past decade, occurring mostly along the headwall on the western, southern and southeastern edges of the crater.

The Batagay megaslump is "still actively growing," the researchers wrote in the study, but there is a limit to how far it can expand. The permafrost remaining inside the crater is only a few feet thick, so "the possibility of further deepening has practically already been exhausted due to the underlying bedrock geology."

This striking satellite photo captured a mysterious arc in an ethereal, iceberg-covered fjord deep within the Arctic Circle. Researchers proposed several possible explanations for the bizarre phenomenon, but  we will likely never find out for sure what caused it.

The Itilliarsuup Kangerlua fjord is part of the Uummannaq Fjord system in Western Greenland, around 460 miles (740 kilometers) north of the country's capital Nuuk. The narrow waterway, which is around 1.6 miles (2.6 km) long, was carved by two glaciers, Sisoortartukassak and Kangilleq, which are separated by a small island at the base of the fjord, according to NASA's Earth Observatory.

During the summer, the fjord's surface becomes littered with thousands of tiny iceberg fragments that have sloughed off from the glaciers, making the water look like a starscape from a deep-field telescope image when viewed from above. However, the most interesting feature in the image is a thin white arc that spans across the fjord. This arc is most likely a displacement wave that was traveling up the fjord away from the ice masses, according to the Earth Observatory.

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The wave may have been caused by a large chunk of ice breaking off from the Kangilleq glacier and falling into the water — similar to the ripples you see when you throw a stone into a perfectly still lake. 

"To me, it does look like a wave caused by a calving event," Josh Willis, an oceanographer at NASA's Jet Propulsion Laboratory, told the Earth Observatory. The "perfect shape" of the arc and orientation of the wave are similar to those of calving events observed in other glaciers, he added.

Dan Shugar,a geomorphologist at the University of Calgary, and Mike Wood, a glaciologist at Moss Landing Marine Laboratories in California, also believe the arc was the result of a calving event, according to the Earth Observatory.

However, the wave could also be caused by an "underwater plume" coming from the Kangilleq glacier, Willis said. Such plumes are made from fresh meltwater that enters salty fjord water from beneath the glacier and rises to the surface, displacing the water around it, he added.

But it is hard to be sure what caused the wave without more data. "Based on satellite images alone, it might never be known with certainty what caused [the] ephemeral feature," Earth Observatory representatives wrote.