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Melting Greenland Ice Sheet May Unleash Methane ‘Fire Ice’: What You Need to Know

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Melting glaciers, such as those in the Ilulissat Icefjord, can trigger significant methane releases.

Gerald Wetzel, Karlsruhe Institute of Technology, Germany

Increasing alarms are being sounded over the potential for melting glaciers to unleash tremendous quantities of greenhouse gases, particularly methane. Recent studies indicate that meltwater is releasing frozen methane hydrates from sediments along the Greenland ice sheet’s edge, a phenomenon reminiscent of patterns observed during the last glacial maximum between 29,000 and 19,000 years ago.

Methane hydrate is created when gas molecules become entrapped within a structure of frozen water molecules, creating what resembles ice, often referred to as “fire ice.” Despite being composed of 85% water, these hydrates pose significant environmental concerns. Burning them could release vast amounts of methane.

These hydrates form under high-pressure and low-temperature conditions present in oceans, permafrost, or beneath glaciers. Some estimates suggest that methane hydrates could hold double the carbon content of all the earth’s coal, oil, and natural gas combined.

However, global warming is altering the cold, high-pressure conditions where methane hydrates exist. For instance, a mystery crater discovered on the Arctic ocean floor in 2014 was believed to have been caused by melting permafrost, which suddenly released pressure on methane hydrates, resulting in a “violent physical explosion,” per the findings of a 2024 survey.

New research indicates that meltwater from Greenland’s glaciers can also release methane hydrates. “We found a new mechanism for releasing methane that was previously thought to be stable,” said Dr. Mat’s Houuse, who led the study from the University of Manchester, UK.

Dr. Hughes and colleagues identified that methane hydrates frequently accumulate between sediment grains at the bottom of Melville Bay in northwestern Greenland. Seismic surveys by oil and gas companies noted 50 large pockmarks on the ocean floor, up to 37 meters deep, near grounding wedges where the last ice sheet once met the ocean floor.

Initially believed to be caused by iceberg movements, investigations through sediment core samples revealed the top sediment layer had minimal methane, despite ideal methane hydrate conditions. The findings indicated substantial fresh water instead of expected seawater, likely due to ice sheet melt. Researchers hypothesize that during the last glacial maximum, meltwater flowing under Melville Bay’s glaciers pushed out methane hydrates through the grounding wedge.

As other glaciers continue to recede under climate change, melting could similarly wash away hydrates at the edges of additional glaciers, posing a significant risk. “In the near past, perhaps 12,000 to 15,000 years ago, there was a considerable methane release. The same could occur tomorrow or in the next century with ongoing ice sheet retreat,” warns Dr. Hughes. “Such events carry alarming implications since we’ve never accounted for them before.”

While the study does not quantify the methane released in Melville Bay, estimates suggest it could be around 130 million tonnes, equating to around two years of fossil fuel emissions. However, Dr. Hughes notes this methane could have been released over a century, rather than in a short timespan, making it a monumental yet singular event.

Additionally, methane dissolves in seawater, and not all of it may escape into the atmosphere, contingent on its saturation levels.

The Antarctic ice sheet likely contains even more methane hydrate than Greenland. Within polar regions, estimates suggest that between 100 billion and 760 billion tonnes of methane are potentially stored in subglacial and ocean hydrates. Even a small release could rival the 48.7 million tonnes of methane currently emitted annually from Arctic and boreal regions, predominantly from wetlands, lakes, and rivers, and could significantly exacerbate climate change.

Methane is already emanating from beneath the Greenland ice sheet. A recent study suggests that snowmelt across western Greenland contributes about 715 tonnes of methane each year. While some may derive from hydrates, it’s more likely to result from ancient plant material transformed into methane gas by bacteria beneath the ice, according to researcher Jade Hutton. This trend could escalate.

“If melting intensifies, it may tap into subglacial regions housing preserved organic carbon stocks that can easily convert to methane,” Hutton states. “This could lead to sizeable future releases.”

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Source: www.newscientist.com

As Greenland’s Ice Sheet Melts, Massive Methane Emissions Could Be Released

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Ilulissat Icefjord in western Greenland

Ilulissat Icefjord in western Greenland

Gerald Wetzel, Karlsruhe Institute of Technology, Germany

Following the last glacial maximum, meltwater has washed frozen methane hydrate from sediments along the edge of Greenland’s ice sheet, raising significant concerns about the potential release of this powerful greenhouse gas due to melting glaciers.

Methane hydrate forms when gas molecules are trapped within a lattice of water molecules and freeze into a solid, often referred to as “fire ice.” Despite being composed of 85% water, its flammability is notable.

This unique structure forms under high pressure and low temperature conditions found in oceans, permafrost, or beneath glacial sediments. Estimates suggest that methane hydrate may contain double the carbon found in all coal, oil, and traditional gas resources on Earth.

However, climate change is disturbing the cold, pressurized environments necessary for the stability of methane hydrate. For instance, some scientists suggest that a mysterious ocean floor crater discovered beneath the Arctic in 2014 was formed by the sudden release of pressure on methane hydrate due to thawing permafrost, described as a “violent physical explosion” in a 2024 study.

Recent research from Greenland indicates that methane hydrate can also be released by glacier meltwater flows. “We discovered a new release mechanism for methane that was assumed to be secure,” says Dr. Mat’s House from the University of Manchester, UK. “What we previously thought was stable is, in fact, methane.”

Hughes and his team recognized that methane hydrate is often found in spaces between sediment grains in Melville Bay, northwestern Greenland. Seismic surveys conducted by oil and gas companies during 2011 and 2013 revealed 50 large pockmarks on the ocean floor, some reaching depths of 37 meters, situated near long grounding wedges. These are locations where the floating ice sheet met the ocean floor during the peak of the last ice age.

Initially, researchers believed these pockmarks were caused by icebergs tipping over. However, drilling sediment cores in the area revealed that the upper sediment layer contained minimal methane, despite ideal temperature and pressure conditions for methane hydrate formation.

Moreover, significant amounts of freshwater were located in the sediment, contradicting the expected seawater findings, a situation only possible due to recent ice sheet melting. The research indicates that during the last glacial maximum, meltwater flowing under glaciers in Melville Bay likely passed through the grounding wedge, pushing out methane hydrate.

As climate change leads to glacier retreat, meltwater might similarly erode hydrates at the edges of other glaciers, Hughes notes. Grounding zone wedges exist across the Arctic, potentially signifying similar risks.

“Perhaps 12,000 to 15,000 years ago, a substantial amount of methane was released. A similar event could occur imminently with ongoing ice sheet retreat,” he warns. “This is concerning as it’s an aspect we’ve yet to fully consider.”

While the study does not estimate the methane released from Melville Bay, Hughes hypothesizes it could be around 130 million tonnes, approximately equivalent to two years’ worth of fossil fuel emissions. However, he notes this methane might have released over a century rather than in a short timeframe, characterizing it as a singular release event.

Furthermore, methane is water-soluble, and depending on saturation levels, not all of it may transition into the atmosphere.

The Antarctic ice sheet likely harbors even more methane hydrate compared to Greenland. Overall, it is estimated that between 100 billion and 760 billion tons of methane exist in subglacial and ocean hydrates across polar regions. A fraction of this could match the 48.7 million tonnes of methane currently released annually from the Arctic and boreal zones, potentially accelerating global warming.

Methane is already seeping from beneath the Greenland ice sheet. A recent study published this month estimates that snowmelt flowing through western Greenland emits around 715 tonnes of methane each year. Though some may stem from hydrates, it’s more likely derived from ancient plant matter converted to methane by bacteria thriving under the ice, led in research by Jade Hutton from the UK Centre for Ecology and Hydrology. This trend may intensify in the future.

“As melting accelerates, it may access regions of the subglacial system harboring well-preserved organic carbon that can be converted to methane,” she predicts. “This could lead to sizable releases in the future.”

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Source: www.newscientist.com

Scientists Discover Secrets of Swirling Plume-Like Structures Beneath Greenland Ice Sheet

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For years, glaciologists have been intrigued by the peculiar plume-like structures hidden beneath the Greenland Ice Sheet. Recent research conducted by scientists from the University of Bergen, NASA’s Goddard Space Flight Center, and the University of Oxford indicates that these enigmatic features are the result of thermal convection—an intriguing process typically associated with Earth’s mantle.

Location of a large plume-like structure (triangle) within the Greenland Ice Sheet. Credit: Leysinger Vieli et al., doi: 10.1038/s41467-018-07083-3 / Law et al., doi: 10.5194/tc-20-1071-2026.

“Typically, we perceive ice as a solid material, so the revelation that parts of the Greenland Ice Sheet experience heat convection—similar to cooking pasta— is both extraordinary and fascinating,” said study co-author Professor Andreas Born from the University of Bergen.

“The realization that thermal convection can occur within ice sheets defies our expectations,” remarked lead author Dr. Robert Loh, also from the University of Bergen.

“However, the ice is at least a million times softer than Earth’s mantle, making the physics align. It’s truly a remarkable phenomenon in nature.”

“These findings could play a crucial role in reducing uncertainties in models predicting ice sheet mass balance and sea level rise,” added Professor Born.

Deep ice is found to be approximately ten times softer than previously assumed, but this does not imply a faster melting rate.

“Enhancing our understanding of ice physics is vital for greater certainty regarding future conditions; nonetheless, softer ice alone does not guarantee accelerated melting or increased sea levels. Further studies are necessary to explore this,” Dr. Loh emphasized.

Although these findings do not predict imminent disasters in Greenland or elsewhere, they underscore the complex and dynamic nature of this region.

“Greenland and its ecosystem are indeed unique,” Dr. Loh commented.

“The ice sheet is over 1,000 years old and is the only one on Earth that coexists with a culture and established communities along its edges.”

“Understanding the processes beneath the ice will better equip us to handle the changes occurring along coastlines globally.”

Read more about the research in the upcoming publication in Cryosphere this month.

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R. Law et al. 2026. Investigating the conditions under which convection is likely to occur within the Greenland Ice Sheet. Cryosphere 20: 1071-1086; doi: 10.5194/tc-20-1071-2026

Source: www.sci.news

Dark Algae Accelerates Greenland Ice Sheet Melting

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Greenland ice sheet algae absorb light and accelerate melting

Laura Halbach

Dark algae growing on the surface of the Arctic ice sheet are likely to expand future coverage, and tend to exacerbate melting, sea level rise and warming.

“These algae are not a new phenomenon.” James Bradley At the Institute of Oceanography in Marseille, France. “But if they bloom more intensely or the flowers bloom more widely, this is an important thing to consider in future projections of sea level rise.”

Greenland's ice sheets, which cover most of the island, are rapidly melting due to rising temperatures, making them the biggest contributor to sea level rise worldwide.

ancylonema Algae under a microscope

Natural Communication

ancylonema Algae species bloom in patches of ice called ablation zones, which are exposed as snow lines recede to the ice sheet every summer. Flowers darken the ice, reduce its reflectivity, absorbing more heat, thereby increasing melting in these regions by an estimated 10-13%.

To better understand this feedback loop, Bradley and his colleagues gathered ancylonema Samples from the southwest tip of the ice sheet were examined for cells using advanced imaging techniques.

The results reveal that algae are highly adapted to malnutritional conditions and suggest that they can invade ice at high elevations with low nutrients.

Global warming already causes snow lines to increase altitude over time, exposing more ice. Ice algae should add yet another layer to these interactions and explain it in future climate forecasts.

“We have been studying glacial algae flowers for several years, and one of the biggest questions that remains is that we can grow to such high numbers in such undernourished ice.” I say that. Christopher Williamson At the University of Bristol, UK, where he was not involved in the project. “A big part of understanding this puzzle is the amount of nutrients needed for glacial algae cells and whether it can efficiently take and store rare nutrients available in the system. This research is cutting edge. They do an amazing job of demonstrating these things using the methodology of

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Source: www.newscientist.com

The impact of the melting Greenland Ice Sheet on ocean currents

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Climate change affects our planet and our lives in many ways. Dry the atmosphere To Increase in home runs Climate change accelerates glacial melt with each Major League Baseball season. Greenland Ice Sheet The land ice mass that covers about 80% of Greenland. When glaciers melt, icebergs form, a process called “iceberg formation.” Glacier collapse Recent climate change has increased the rate at which icebergs are flowing from the Greenland Ice Sheet into the North Atlantic.

Scientists have found that in the past, large increases in the rate of glacial collapse have disrupted important ocean current systems in the Atlantic Ocean. Atlantic Meridional Gyre Or as the AMOC, it carries warm water north and cold water south, affecting global temperatures and moving nutrients across the Atlantic Ocean, meaning that disrupting the AMOC could change the climate and destabilize marine ecosystems. Recently, scientists conducted a study to determine whether the current increase in glacier collapse could disrupt the AMOC.

For this study, the researchers developed a method to quantify glacial runoff during past periods of increased glacial collapse in the North Atlantic that disrupted the AMOC. Heinrich Event They began by looking at present-day glaciers in the North Atlantic and the Arctic. As icebergs break up, they deposit sediment. This sediment includes sand and rocks from the land below the ice sheet, as well as the remains of organisms that lived on the ice sheet. When the icebergs melt at sea, the sediment is released and sinks to the ocean floor.

Scientists observed modern glaciers melting and measured the average amount of sediment, by volume, that they released. Using this average, the researchers estimated how much ice was released during past Heinrich events, based on the amount of sediment that was deposited on the floor of the North Atlantic Ocean.

Scientists used this method to estimate the total amount of ice lost during 10 Heinrich events (the last of which) that occurred over the past 140,000 years. Glacial Cycle Previous scientists had determined the duration of Heinrich events, which allowed the researchers to estimate the ice runoff rate during each event. The researchers compared their estimated runoff rates to current ice runoff rates and found that current ice runoff rates are similar to those of previous mid-sized Heinrich events that disrupted the AMOC. However, the scientists who conducted the study also noted that the AMOC is currently stable.

The researchers suggested two factors that could help explain why the current increase in glacial collapse is not disrupting the AMOC as much as it has in the past. First, the researchers think that the AMOC was stronger when the current glacial runoff rate began to increase than it was at the start of past Heinrich events, which may make the current AMOC more resistant to disruptions. Second, each of the 10 Heinrich events the scientists used in their study lasted about 250 years, while the faster glacial collapse seen today may have been due to a slowdown in the early Heinrich events. It began in recent decades They suggested that AMOC collapse could only occur after a longer period of increased glacier calving than has happened previously.

If the rate of glacial calving continues to increase by the time the AMOC collapses, the size of the Greenland Ice Sheet may limit its influence on the AMOC. The researchers noted that if the Greenland Ice Sheet continues to melt at its current rate, the rate of calving will slow before 250 years have passed. The icebergs that caused the Heinrich events in the last glacial cycle broke off from a much larger ice sheet. Laurentide Ice Sheet It no longer exists.

The scientists who conducted the study said that freshwater runoff from the melting Greenland Ice Sheet could also disrupt the AMOC, but its impact would be less severe than ice runoff. However, they noted that freshwater runoff is likely to increase as glacial collapse slows in the coming decades, which could have unpredictable consequences. The researchers suggested that the scientific community should continue their work to model the impacts of a melting Greenland Ice Sheet as accurately as possible, because, in their words, “the fate of the AMOC remains uncertain.”


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Source: sciworthy.com

Hot water leaking beneath Antarctic ice sheet may quicken melting

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Aerial photo of the Antarctic ice sheet

David Vaughn/BAS

Antarctica’s melting ice sheet could retreat faster as warmer ocean water invades underneath it, and rising ocean temperatures could trigger a “runaway” feedback effect that pushes warm water further inland, melting even more ice and accelerating sea-level rise.

As the climate warms, the future of Antarctica’s vast ice sheet remains uncertain, and predictions vary widely about how quickly it will melt and therefore how much it will contribute to sea-level rise. One dynamic that researchers have only recently begun to recognize as a key factor is the intrusion of warmer ocean water beneath the ice.

“The mechanisms of invasion are much more powerful than we previously understood.” Alexander Bradley At the British Antarctic Survey.

Such intrusions are driven by density differences between the freshwater flowing out from beneath the ice sheet and the warmer waters where the ice meets the sea floor, known as the grounding line. They are difficult to observe directly because they occur hundreds of meters beneath the ice, but simulations suggest that in some places the warm waters could extend several kilometers inland.

One model by Alexander Lovell Researchers from the Georgia Institute of Technology in Atlanta found that widespread ice-sheet intrusion could add heat from below, lubricating ice flow along bedrock and more than doubling ice loss from the ice sheet.

Bradley and his colleagues Ian Hewitt Using their model, Oxford researchers explained how the shape of cavities in the ice changes as the ice melts, altering how ocean water flows in.

The researchers found that once ocean water reaches a certain temperature threshold, ice from the ice sheet melts faster than it can be replaced by outflowing ice. If this cavity grows larger, more water could flow under the ice sheet and penetrate further inland, creating a so-called “runaway” positive feedback effect.

“Small changes in ocean temperature lead to dramatic changes in how far warm water can intrude,” Bradley said. The ocean warming needed to cause this effect is within the range expected this century, he said, but models cannot yet predict it for specific ice sheets, and not all ice sheets are equally susceptible to such intrusions.

“This positive feedback could lead to much more intrusion than we thought,” Lovell says. “Whether that’s a tipping point that leads to unrestrained intrusion of ocean water beneath the ice sheet is probably a stretch.”

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Source: www.newscientist.com