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vox_mundi

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Re: Permafrost general science thread
« Reply #200 on: August 30, 2022, 06:27:31 PM »
Arctic Lakes Are Vanishing In Surprise Climate Finding
https://phys.org/news/2022-08-arctic-lakes-climate.html



The Arctic is no stranger to loss. As the region warms nearly four times faster than the rest of the world, glaciers collapse, wildlife suffers and habitats continue to disappear at a record pace.

Now, a new threat has become apparent: Arctic lakes are drying up, according to research published in the journal Nature Climate Change. The study, led by University of Florida Department of Biology postdoctoral researcher Elizabeth Webb, flashes a new warning light on the global climate dashboard.



Webb's research reveals that over the past 20 years, Arctic lakes have shrunk or dried completely across the pan-Arctic, a region spanning the northern parts of Canada, Russia, Greenland, Scandinavia and Alaska. The findings offer clues about why the mass drying is happening and how the loss can be slowed.

The vanishing lakes act as cornerstones of the Arctic ecosystem. They provide a critical source of fresh water for local Indigenous communities and industries. Threatened and endangered species, including migratory birds and aquatic creatures, also rely on the lake habitats for survival.

The lake decline comes as a surprise. Scientists had predicted that climate change would initially expand lakes across the tundra, due to land surface changes resulting from melting ground ice, with eventual drying in the mid-21st or 22nd century. Instead, it appears that thawing permafrost, the frozen soil that blankets the Arctic, may drain lakes and outweigh this expansion effect, says Webb. The team theorized that thawing permafrost may decrease lake area by creating drainage channels and increasing soil erosion into the lakes.

"Our findings suggest that permafrost thaw is occurring even faster than we as a community had anticipated," Webb said. "It also indicates that the region is likely on a trajectory toward more landscape-scale drainage in the future."

In addition to rising temperatures, the study also revealed that increases in autumn rainfall cause permafrost degradation and lake drainage. "It might seem counterintuitive that increasing rainfall reduces surface water," said Jeremy Lichstein, Webb's advisor and a co-author of the study. "But it turns out the physical explanation was already in the scientific literature: rainwater carries heat into the soil and accelerates permafrost thaw, which can open up underground channels that drain the surface."



... "The snowball is already rolling," Webb said, stating that we need to act now to slow these changes. "It's not going to work to keep on doing what we're doing."

Elizabeth E. Webb et al, Permafrost thaw drives surface water decline across lake-rich regions of the Arctic, Nature Climate Change (2022).
https://www.nature.com/articles/s41558-022-01455-w
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Sebastian Jones

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Re: Permafrost general science thread
« Reply #201 on: September 05, 2022, 04:40:29 AM »
I  get my water from a small creek that is conveniently located and of adequate gradient such that I have gravity feed water during the warm seasons.
Last summer it began  running muddy after heavy rains, this summer it has barely cleared up at all and after a heavy - or even moderate- rain, there is so much silt coming down that it plugs up the water line.
Today I slogged through a couple of kms of alder and willow jungle in the rain to where the valley shallows, the moss is deep and the black spruce are diminished.
Here I found the cause of the silting.
From what I can tell, a block of massive ice thawed underground which collapsed the surface- thermokarst action- and the creek made contact with the ice rich permafrost.
The water rapidly extended the thawed ground such that I could see large blocks of ice exposed and mud running off the exposed permafrost.
It is possible that, now it has been exposed, the ice rich permafrost, which has been frozen since the Pleistocene, will continue to thaw, and extend back uphill in a retrogressive thaw slump.
I have a couple of not awesome photos which I'll post separately because my internet connection is poor.

Sebastian Jones

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Re: Permafrost general science thread
« Reply #202 on: September 05, 2022, 04:43:35 AM »
Pic one as promised.
This shows the exposed ice rich silt, and the insulating moss and vegetation layer above it. The exposed face is about 3M high.

Sebastian Jones

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Re: Permafrost general science thread
« Reply #203 on: September 05, 2022, 04:53:48 AM »
Photo two shows some exposed pure  ice.

Sebastian Jones

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Re: Permafrost general science thread
« Reply #204 on: September 05, 2022, 04:57:31 AM »
Phew. They loaded.
Now that I know where this site is, I'll keep an eye on it, and if there is interest, will post updates from time to time.

HapHazard

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Re: Permafrost general science thread
« Reply #205 on: September 05, 2022, 05:19:18 AM »
Fun times innit SJ
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oren

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Re: Permafrost general science thread
« Reply #206 on: September 05, 2022, 07:33:52 AM »
Yeah, that sounds bad.

uniquorn

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Re: Permafrost general science thread
« Reply #207 on: September 05, 2022, 10:26:26 AM »
Pic one as promised.
This shows the exposed ice rich silt, and the insulating moss and vegetation layer above it. The exposed face is about 3M high.

Does it face south?

kassy

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Re: Permafrost general science thread
« Reply #208 on: September 05, 2022, 05:29:09 PM »
Phew. They loaded.
Now that I know where this site is, I'll keep an eye on it, and if there is interest, will post updates from time to time.

Please do so. It will be interesting to see the developments.
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johnm33

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Re: Permafrost general science thread
« Reply #209 on: September 05, 2022, 06:11:20 PM »
How does it 'sit' in the terrain? Does the stream emerge from it's base? When I read above about the lakes dissappearing my first thought was 'is the ice melting from below' creating subterranean streams?

HapHazard

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Re: Permafrost general science thread
« Reply #210 on: September 05, 2022, 08:20:42 PM »
SJ's recent posts reminded me of my road trip to the Arctic Ocean (it's posted in "The Rest" forum) a month ago - I saw a number of permafrost thaw-slumps along the way. I didn't think to take any pictures of them at the time (I didn't feel like taking pix of something so depressing), now I wish I did.
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Tor Bejnar

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Re: Permafrost general science thread
« Reply #211 on: September 05, 2022, 08:52:03 PM »
Just like sea ice, permafrost (when it melts) melts from both top and bottom, for somewhat the same causes.  The 'center' of the Earth is hot and radiates heat, and where/when it is cold at the surface, we find a 0oC equilibrium somewhere between a millimeter [obviously not a "permafrost" location] and a couple kilometers down.  Just like sea ice, permafrost will be coldest at the surface after a long period of 'hard' freezing and will be coldest some distance down after a period of surface warm. (In very thick permafrost, I'm sure there are "waves" of colder and less cold, associated with, perhaps, decades of colder average surface temps and decades of warmer average surface temps, but this is speculation as I've never particularly studied permafrost.) 

But to answer the question of sub-permafrost streams, it depends on the nature of the bedrock or sediments below (or at the base of) the permafrost.  ("Streams" will not be found in granite [except for in fault gouge or well developed fracture systems] but could easily form in kaarst [limestone] or in river-laid gravels.)

Permafrost is know for it's high H2O content, from meters-thick sections of "pure" ice to "frozen mud" (both pictured above), but when permafrost extends into bedrock, there might not be much space for 'water'!
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johnm33

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Re: Permafrost general science thread
« Reply #212 on: September 05, 2022, 11:50:07 PM »
Subterranean was a bad choice of wording, I really meant directly beneath the permafrost where that meets rock. I guess that with limestone at least the water can escape whereas with something less porous there's a slow build towards 00 before the 'dam' breaches and a slump occurs?
So given the extent of lakes and pools in permafrost areas does this suggest periodic draining of lakes is 'normal'? or perhaps that the below zero zone is now less than the 2km down, or whatever it was previously? Is there a lake or body of water nearby at an higher elevation?

Sebastian Jones

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Re: Permafrost general science thread
« Reply #213 on: September 06, 2022, 07:17:25 AM »
Pic one as promised.
This shows the exposed ice rich silt, and the insulating moss and vegetation layer above it. The exposed face is about 3M high.

Does it face south?
No, it faces north.

Sebastian Jones

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Re: Permafrost general science thread
« Reply #214 on: September 06, 2022, 07:26:51 AM »
How does it 'sit' in the terrain? Does the stream emerge from it's base? When I read above about the lakes dissappearing my first thought was 'is the ice melting from below' creating subterranean streams?

No. The stream is pretty close to its 'source' there. The valley bottom is basically one big  sponge of moss and the water is just flowing through and over it. It is not really a creek, except where the ice collapsed. I doubt very much that the ice is melting from below there. I most places like this (valley bottom, well insulated) the permafrost is about 60m deep here.

kassy

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Re: Permafrost general science thread
« Reply #215 on: October 17, 2022, 12:39:15 PM »
Permafrost Emissions Must Be Factored Into Global Climate Targets, Says Study

By the end of this century, permafrost in the rapidly warming Arctic will likely emit as much carbon dioxide and methane into the atmosphere as a large industrial nation, and over time potentially more than the United States has emitted since the start of the Industrial Revolution.

But that’s only one possible future for the vast stores of carbon locked in formerly perennially frozen but now-thawing ground in the Arctic. Using more than a decade of synthesis science and regional models, a new study published in Annual Review of Environment and Resources forecasts cumulative emissions from the permafrost regions through 2100 under low, medium and high warming scenarios.

“We hope that these forecasts of future Arctic carbon emissions not only update the scientific picture but act as new guide rails for policymakers who are working to stabilize the climate and avoid exceeding temperature targets,” said lead author Ted Schuur of Northern Arizona University.

The team estimates that under a low warming scenario—one that could be achieved if the global community limited warming to 2 degrees C or below by reducing fossil fuel emissions—permafrost would release 55 billion metric tons of greenhouse gases by the end of the century in the form of carbon dioxide and methane. If nothing is done to mitigate climate warming, the study estimates the Arctic could release 232 metric tons.

The team’s projections go beyond previous international forecasts by accounting for hydrological and biogeochemical dynamics, and tipping points unique to the permafrost zone.

For instance, scientists are witnessing abrupt thawing in many permafrost regions, where rapid melting of ground ice in permafrost causes the land surface to collapse. This forms lakes or causes other changes to surface hydrology. Once formerly frozen ground erodes or subsides, the carbon stored there can enter the atmosphere via microbial respiration. Such rapid nonlinear shifts quickly and permanently change permafrost’s ability to store carbon and could toggle large swaths of the Arctic from taking up carbon to giving it off. Recent estimates suggest that one-fifth of current permafrost terrain is vulnerable to abrupt thaw.

“Once permafrost carbon emissions increase in response to climate warming as some models predict, there won’t be a way for us to stop that process,” said coauthor Roísín Commane, an atmospheric scientist at the Columbia  Climate School’s Lamont-Doherty Earth Observatory, and assistant professor of Earth and Environmental Sciences. “We may need to reduce our fossil fuel emissions much sooner than currently planned by many governments to avoid triggering possible tipping points in Earth’s climate.”

The potential to cross both regional and system-wide tipping points is one reason the story of Arctic carbon and its future security remains only partially written. The new study describes nine different futures based on how climate warming progresses, and what actions global leaders take to reduce fossil fuel emissions.

“Permafrost emissions will be a large and substantial contributing factor to atmospheric greenhouse gases, no matter which of the possible scenarios becomes reality,” said Guido Grosse, of the Alfred Wegener Institute in Potsdam, Germany and coauthor of the study. “But there will be huge differences between mitigation scenarios that matter to the overall global carbon budget.”

and more:
https://news.climate.columbia.edu/2022/10/17/permafrost-emissions-must-be-factored-into-global-climate-targets-says-study/
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kassy

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Re: Permafrost general science thread
« Reply #216 on: February 22, 2023, 08:41:21 PM »
Sinking tundra surface unlikely to trigger runaway permafrost thaw

Oak Ridge National Laboratory scientists set out to address one of the biggest uncertainties about how carbon-rich permafrost will respond to gradual sinking of the land surface as temperatures rise. Using a high-performance computer simulation, the research team found that soil subsidence is unlikely to cause rampant thawing in the future.

This permanently frozen landscape in the Arctic tundra, which has kept vast amounts of carbon locked away for thousands of years, is at risk of thawing and releasing greenhouse gases into the atmosphere.

The United Nation's Intergovernmental Panel on Climate Change has identified the possibility of soil subsidence leading to a feedback loop that could trigger a rapid thaw as a major concern in the decades ahead. Accelerated thawing caused by uneven land subsidence has been observed on smaller scales over shorter time frames, but the IPCC's assessments were uncertain as to what may happen over the long term.

That's where ORNL stepped in with its Advanced Terrestrial Simulator, or ATS, a highly accurate, physics-based model of the region's hydrology fed by detailed, real-world measurements to help scientists understand the land's evolution.

What they found is that even though the ground will continue to sink as big ice deposits melt, the uneven subsidence also leads to a drier landscape and limits the process's acceleration through the end of the century, as described in the Proceedings of the National Academy of Sciences.

"Improved drainage results in a drier landscape over a decadal timescale, and the process then becomes self-limiting," said Scott Painter, who leads the Watershed Systems Modeling group at ORNL.

...

https://www.sciencedaily.com/releases/2023/02/230221180110.htm
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morganism

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Re: Permafrost general science thread
« Reply #217 on: March 23, 2023, 06:16:52 AM »
The Toxic Threat in Thawing Permafrost

Scientists are tracking neurotoxic methylmercury production in North America’s largest peatland.

Wildfires and volcanoes belch mercury and since the Industrial Revolution so, too, do coal-burning power plants and factories. Warm air currents carry mercury in its inorganic heavy metal form to the Arctic where it settles into the soil and vegetation before being safely locked away in the deeply frozen permafrost.

In its inorganic form, mercury is less threatening to people. But as the permafrost thaws, says Kirkwood, mercury is finding its way into the soil and into the regions’ many ponds, rivers, and lakes. Once there, microbes can convert inorganic mercury into the form to be concerned about: neurotoxic methylmercury."

Indigenous peoples have seen firsthand how the permafrost is changing.

“Walking on permafrost is like walking on really hard ground, like gravel,” says Hunter. When there’s permafrost, he says, “there’s all kinds of flora. There’s berries, vegetation that animals feed on. We collect wild tea.”

But once the permafrost thaws, he says, “the environment turns into a swampland. … You can’t even walk, you’d sink.” Along with the disappearing permafrost “go the animals. They move higher and higher into the Arctic. Muskox has disappeared and a few shorebirds we used to have—they’re moving north.

That’s where Kirkwood’s research comes in. By drilling and taking core samples of the permafrost, then measuring the amount of inorganic mercury while at the same time sequencing the DNA of everything in the soil, he hopes to better understand how methylmercury gets produced in thawing permafrost. Once he knows that, he can figure out where the threat is largest by looking at where mercury methylating microbes and inorganic mercury overlap.

https://hakaimagazine.com/news/the-toxic-threat-in-thawing-permafrost/
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kassy

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Re: Permafrost general science thread
« Reply #218 on: March 23, 2023, 10:32:34 PM »
The animals and plants just don´t like the swampy conditions.

Quote
So far, Kirkwood’s initial findings show reason for hope. Previous Arctic-scale estimates of inorganic mercury abundance have vastly overestimated how much mercury is being stored in the Hudson Bay Lowlands. Kirkwood’s cores show mercury levels 10 times lower. But that doesn’t mean all is well. In thermokarst fens, meltwater ponds created when iceberg-like permafrost chunks thaw, methylmercury levels are higher than in the surroundings. As more permafrost thaws and these ponds connect, methylmercury production will likely increase. And if this mercury reaches the bay, biomagnification could cause it to build up to high concentrations, making its way up the food chain from algae to the tissue of fish that people catch and eat.

So this is more of a longer term problem.
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vox_mundi

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Re: Permafrost general science thread
« Reply #219 on: July 06, 2023, 09:50:34 PM »
Arctic Permafrost Runoff Driven by Climate Change
https://phys.org/news/2023-07-arctic-permafrost-runoff-driven-climate.html



Rising temperatures and changes in precipitation are driving increases to streamflow in areas of high-latitude North America where permafrost dominates the landscape.

"We saw long-term trends of increasing streamflows in the Arctic that reflect how deeper layers of the permafrost are thawing and releasing water," said Katrina Bennett, a hydrologist at Los Alamos National Laboratory and lead author of a recent paper on permafrost streamflows in the journal Frontiers in Water. "In general, we found that all areas with at least some permafrost coverage were experiencing higher streamflows overall and higher minimum flows as the Arctic climate warms up."

Bennett and a team from Los Alamos and the International Arctic Research Center at the University of Alaska Fairbanks analyzed diverse, challenging data sets for hydrology in the permafrost region.

The analysis makes it clear that changes in precipitation and higher temperatures under climate change are driving these trends of increasing streamflow from permafrost melt over the 46-year study period.

Other variables, including the extent of permafrost coverage, became more important in the past 32 years, according to the study.

Areas with more than 50% permafrost coverage had significant increases in mean streamflow, while all areas, including those with much less coverage, saw increased minimum flows.

In areas dominated by permafrost, maximum streamflow and its timing are shifting variably, Bennett said, with significant increases during fall and winter.

"These findings appear to indicate that permafrost is playing an increasingly focal role in changing trends across all components of the streamflow seasonally," Bennett said. "We seem to be seeing enhanced thawing of frozen grounds in more recent years of the study, as the high latitudes experience more precipitation and warmer temperatures."

The work is published in the journal Frontiers in Water.


Five-year rolling means for mean streamflow (scaled and centered around 3, unitless) across permafrost groups for seasons and annually. Time periods for the rolling means are the 1980 to 2021 (42 years).

Katrina E. Bennett et al, Recent streamflow trends across permafrost basins of North America, Frontiers in Water (2023).
https://www.frontiersin.org/journals/water/articles/10.3389/frwa.2023.1099660/full
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vox_mundi

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Re: Permafrost general science thread
« Reply #220 on: September 19, 2023, 02:32:38 PM »
Near-Surface Permafrost Could Be Nearly Gone By 2100, Scientists Conclude
https://phys.org/news/2023-09-near-surface-permafrost-scientists.html



Most of Earth's near-surface permafrost could be gone by 2100, an international team of scientists has concluded after comparing current climate trends to the planet's climate 3 million years ago.

The team found that the amount of near-surface permafrost could drop by 93% compared to the preindustrial period of 1850 to 1900. That's under the most extreme warming scenario in the latest report of the Intergovernmental Panel on Climate Change.

By 2100, Earth's near-surface permafrost, within the upper 10 to 13 feet of the soil layer, may exist only in the eastern Siberian uplands, Canadian High Arctic Archipelago and northernmost Greenland—just like it did in the mid-Pliocene Warm Period.

"Our study indicates dramatically smaller-than-present near-surface permafrost extent in the geological past, under climate conditions analogous to those expected if global warming continues unabated," the authors write.

Professor emeritus Vladimir Romanovsky of the University of Alaska Fairbanks Geophysical Institute is among the co-authors. Romanovsky is a leading scientist in permafrost research.

"The loss of this much near-surface permafrost over the next 77 years will have widespread implications for human livelihoods and infrastructure, for the global carbon cycle and for surface and subsurface hydrology," Romanovsky said. "This research rings yet another alarm bell for what is happening to Earth's climate."

Simulations of the mid-Pliocene Warm Period climate are similar to the climate projection for the end of this century under the fossil-fueled development pathway in the latest report of the IPCC. That pathway is the bleakest of five presented for future society.

"Based on our findings, the future of Northern Hemisphere near-surface permafrost appears bleak," the authors write. "Continued climate warming and related near-surface permafrost degradation may cause changes in ambient and environmental conditions that humans have not yet experienced, implying an imperative to further highlight the importance of permafrost degradation."

Donglin Guo et al, Highly restricted near‐surface permafrost extent during the mid-Pliocene warm period, Proceedings of the National Academy of Sciences (2023).
https://www.pnas.org/doi/10.1073/pnas.2301954120
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kassy

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Re: Permafrost general science thread
« Reply #221 on: September 23, 2023, 07:01:42 PM »
Greater Snowfall Speeds the Melting of Arctic Tundra, Study Finds

With climate change, parts of the Arctic are seeing greater snowpack. Paradoxically, a thick blanket of snow can speed the melting of permafrost underneath, releasing buried stores of carbon, new research shows.

The insight comes from a decades-long experiment near Toolik Lake in northern Alaska. Starting in 1994, scientists there began covering a swath of tundra in three to four times the usual amount of snowpack, finding that, as the region warmed, this patch actually thawed faster than other areas. Scientists said the added snow acted like a blanket during the cold months, holding in summer heat while keeping out frigid air.

As permafrost melted, microbes began to consume long-frozen plant matter in the ground, producing carbon dioxide as a byproduct. The patch of tundra with extra insulation became a year-round source of emissions. Even as shrubs began to grow on the once-frozen ground and soak up some carbon dioxide, the emissions from microbes remained greater still, according to the new study, published in AGU Advances.

The new findings, authors write, show that greater snowfall “will cause earlier-than-expected losses of ancient carbon from permafrost and further accelerate climate change.”

https://e360.yale.edu/digest/arctic-snow-emissions-climate-change

More Snow Accelerates Legacy Carbon Emissions From Arctic Permafrost

Abstract
Snow is critically important to the energy budget, biogeochemistry, ecology, and people of the Arctic. While climate change continues to shorten the duration of the snow cover period, snow mass (the depth of the snow pack) has been increasing in many parts of the Arctic. Previous work has shown that deeper snow can rapidly thaw permafrost and expose the large amounts of ancient (legacy) organic matter contained within it to microbial decomposition. This process releases carbonaceous greenhouse gases but also nutrients, which promote plant growth and carbon sequestration. The net effect of increased snow depth on greenhouse gas emissions from Arctic ecosystems remains uncertain. Here we show that 25 years of snow addition turned tussock tundra, one of the most spatially extensive Arctic ecosystems, into a year-round source of ancient carbon dioxide. More snow quadrupled the amount of organic matter available to microbial decomposition, much of it previously preserved in permafrost, due to deeper seasonal thaw, soil compaction and subsidence as well as the proliferation of deciduous shrubs that lead to 10% greater carbon uptake during the growing season. However, more snow also sustained warmer soil temperatures, causing greater carbon loss during winter (+200% from October to May) and year-round. We find that increasing snow mass will accelerate the ongoing transformation of Arctic ecosystems and cause earlier-than-expected losses of climate-warming legacy carbon from permafrost.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023AV000942
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kassy

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Re: Permafrost general science thread
« Reply #222 on: October 13, 2023, 03:52:01 PM »
Flooding that closed Alaska's Dalton Highway also caused widespread ground sinking

The massive 2015 flooding of the Sagavanirktok River in northern Alaska had immediate impacts, including closure of the Dalton Highway for several days, but it also contributed to longer-term ground subsidence in the permafrost-rich region.

That's the finding by assistant professor Simon Zwieback at the University of Alaska Fairbanks Geophysical Institute in a study published Sept. 27 by the journal Permafrost and Periglacial Processes.

...

"What previously hadn't been known is that subsequent to the flood there were diffuse and variable changes to tundra and to this permafrost landscape," Zwieback said. "In particular, we observed that in areas that were flooded, there were several hotspots of subsidence with subsidence exceeding 3 inches over a few years. And we also observed many more areas with less pronounced but still measurable sub-segments.

"We also observed a green-up and a wettening of the landscape, which was also quite variable," he said. "All of this is important for understanding how these landscapes react to floods."

...

The river's massive floodwaters exacerbated what the authors describe as a "complicated relationship" between rivers and their floodplains in regions of continuous permafrost. Human activity in the area, driven by continued expansion of the Prudhoe Bay oilfield and the presence of the Dalton Highway, has also interfered with natural drainage.

The flood may have stimulated subsidence by warming the ground, causing ground ice to melt, the authors state. Warming can be due to increased wetness, disturbance to the protective layer of organic matter or sediment deposition, allowing more heat to penetrate.

Zwieback analyzed satellite data from 2015 through 2019 to estimate ground deformation over the post-flood years.

"What we did observe from space was widespread but also quite variable subsidence," Zwieback said.

Subsidence was most pronounced in flooded locations and was most active in the two years after the flood.

"We interpret the subsidence that we observed with remote sensing to be largely due to melting of ground ice," Zwieback said. "Soils in the area contain substantial quantities of ice in the form of ice wedges and segregated ice, small lenses of ice as opposed to big chunks."

Ice wedges are generally anywhere from about 3 to 10 feet across and about 6 to 10 feet deep at their narrow bottom. They form regular networks and in the study area are typically found about 30 feet apart.

"One of the main complicating factors here is that initial subsidence can trigger changes at the surface, such as ponding of water," Zwieback said. "The surface becomes darker and warmer. And that means more thawing underneath, because you have changed the surface conditions."

...

https://www.sciencedaily.com/releases/2023/10/231011202424.htm
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neal

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Re: Permafrost general science thread
« Reply #223 on: December 21, 2023, 06:18:52 PM »
Rivers in Alaska turning rusty and acidic via thawing permafrost

...It was a cloudy July afternoon in Alaska's Kobuk Valley National Park, part of the biggest stretch of protected wilderness in the U.S. We were 95 kilometers (60 miles) from the nearest village and 400 kilometers from the road system. Nature doesn't get any more unspoiled. But the stream flowing past our feet looked polluted. The streambed was orange, as if the rocks had been stained with carrot juice. The surface glistened with a gasolinelike rainbow sheen. “This is bad stuff,” said Patrick Sullivan, an ecologist at the University of Alaska Anchorage.

Sullivan, a short, bearded man with a Glock pistol strapped to his chest for protection against Grizzly Bears, was looking at the screen of a sensor he had dipped into the water. He read measurements from the screen to Roman Dial, a biology and mathematics professor at Alaska Pacific University. Dissolved oxygen was extremely low, and the pH was 6.4, about 100 times more acidic than the somewhat alkaline river into which the stream was flowing. The electrical conductivity, an indicator of dissolved metals or minerals, was closer to that of industrial wastewater than the average mountain stream. “Don't drink this water,” Sullivan said.

Less than a dozen meters away the stream flowed into the Salmon River, a ribbon of swift channels and shimmering rapids that winds south from the snow-dimpled dun peaks of the Brooks Range. This is the last frontier in the state known as “the last frontier,” a 1,000-kilometer line of pyramidlike slopes that wall off the northern portion of Alaska from the gray, wind-raked Arctic Coast.

One of the most remote and undisturbed rivers in America, the Salmon has long been renowned for its unspoiled nature. When author John McPhee paddled the Salmon in 1975, it contained “the clearest, purest water I have ever seen flowing over rocks,” he wrote in Coming into the Country, an Alaska classic. A landmark 1980 conservation act designated it a wild and scenic river for what the government called “water of exceptional clarity,” deep, luminescent blue-green pools and “large runs of chum and pink salmon.”

Now, however, the Salmon is quite literally rusting. Tributary streams along one third of the 110-kilometer river are full of oxidized iron minerals and, in many cases, acid. “It was a famous, pristine river ecosystem,” Sullivan said, “and it feels like it's completely collapsing now.” The same thing is happening to rivers and streams throughout the Brooks Range—at least 75 of them in the past five to 10 years—and probably in Russia and Canada as well. This past summer a researcher spotted two orange streams while flying from British Columbia to the Northwest Territories. “Almost certainly it is happening in other parts of the Arctic,” said Timothy Lyons, a geochemist at the University of California, Riverside, who's been working with Dial and Sullivan....

....The second night, we camped among spindly spruce trees on the gravel shore across from where Anaktok Creek, a toxic orange tributary, runs through a long, winding valley and into the Salmon. Dial and Sullivan, who knew the Anaktok from previous trips, wanted to hike half a dozen kilometers up into the valley and float back down, sampling the creek and the tiny streams that feed it. The next morning we grabbed several water-sampling kits each, paddled across the river, packed up our rafts and started up the northern slope. As we got higher we could see across to the southern side of the valley, and we discovered a startling sight. An expanse of green tundra maybe 100 meters long looked as if it had been burned—only there hadn't been any wildfire.

We scrambled up a hill and began moving along the broad ridgeline, and after more than an hour we came across an ugly black sore on our side of the valley. Twigs of dead lingonberry and dryas shrubs drooped onto dirt the color of fresh asphalt. A channel of water trickled out of the dark ground. It was too shallow to measure with the sampling kit, so McCarthy offered to sacrifice his Nalgene water bottle. He took one last swig and dumped its contents, then slowly refilled it from the seep. When Sullivan dipped a sensor into the bottle, it showed a pH of 2.95, like vinegar. The burn was from acid. “If it's got that low of a pH ... it's actively burning,” Sullivan said. “There's at least a dozen burns in this valley,” Dial added....


https://www.scientificamerican.com/article/why-are-alaskas-rivers-turning-orange/

HapHazard

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Re: Permafrost general science thread
« Reply #224 on: December 21, 2023, 09:30:23 PM »
Crazy stuff. It actually reminds me of a stream that ran behind the house I grew up in, there were a few sections which were orange like that. It was iron bacteria. Interesting organism. Related interesting video:

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morganism

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Re: Permafrost general science thread
« Reply #225 on: December 28, 2023, 06:22:50 AM »
Nice article on the differences between permafrost and periglacial areas, with a digression into weather tendencies and thermal radiation zones tossed in.

https://www.severe-weather.eu/learnweather/cryosphere-theory/what-is-permafrost-rrc/
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morganism

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Re: Permafrost general science thread
« Reply #226 on: January 19, 2024, 11:24:54 PM »
(with more rain in winters, gonna be a lot more of this. How it will affect permafrost and methane)
(...)
 Where and how frost quakes occur

The phenomenon isn’t unique to the US Midwest; frost quakes have also been reported in New England, Canada and parts of Scandinavia. They can happen in rural or urban areas.

Frost quakes typically occur under a certain set of winter conditions, Ford said — after a wet, rainy period and when there’s little snow, which has an insulating effect, on the ground. How common the quakes are is unclear since there isn’t much research on them yet.

“What we need is for the soil to be nearly saturated with water so that there’s very little airspace to fill,” he said. “And then you need a rapid freeze.”

Once the soil is frozen, it acts like a different material. It becomes more solid, not shrinking and swelling as it normally would.

“That water in the soil freezes and expands … within the soil and essentially cracks or fractures the (frozen) soil almost like a rock. So it’s that fracturing that makes (the) popping and booming sound.”
(snip)
 Roads and other areas cleared of snow were thought to be particularly vulnerable to frost quakes. However, the latest study suggested that some frost quakes occurred in wetlands and swamps, where water accumulates. These areas typically had snow cover, Moisio said, thus the finding surprised the research team.

To understand whether frost quakes are increasing, the team plans to monitor the same areas this winter and next. The researchers also hope to map how common frost quakes are in other areas of the country.

Moisio said that wetter winters and less stable winter temperatures due to climate change could lead to frost quakes becoming more frequent.

“There will be not as much snow in the future in Scandinavia at these latitudes where we are,” he said.

Instead, he said, it will rain more.

“This, I think, might create even more dramatic events … because this will increase water in the subsurface.”

Leung agreed. “We have no evidence that they are becoming more frequent,” he said. “However, the overall decreasing snow depth trend due to climate change in theory can make the ground more susceptible to frost quakes because snow is no longer insulating the ground.”

https://www.cnn.com/2024/01/19/world/frost-quakes-cold-weather-seismic-phenomenon-scn/index.html

Frost quakes in wetlands in northern Finland during extreme winter weather conditions and related hazard to urban infrastructure

https://egusphere.copernicus.org/preprints/2023/egusphere-2023-1853/
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vox_mundi

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Re: Permafrost general science thread
« Reply #227 on: February 08, 2024, 05:19:08 PM »
A New Map Tool for Monitoring Pan-Arctic Trends of Permafrost Landscape Change
https://phys.org/news/2024-02-tool-pan-arctic-trends-permafrost.html



Arctic PASSION has recently published the Arctic Landscape EXplorer (ALEX), which contains data on satellite-derived trends in land surface changes at 30-meter resolution for the entire Arctic permafrost region for the 20 years from 2003 to 2022. The freely-available online tool features an easy-to-use and well-explained map interface and was developed specifically for non-experts to meet the information needs of local Arctic communities living in areas with permafrost.

The work is published in the journal PANGAEA.

The tool includes a localized view of the information provided and a storytelling component, and parts of the website will be available in multiple Arctic languages soon. Consultations with local representatives and stakeholders from Alaska aimed to ensure that their actual information needs are met.

"Dozens of lakes in Alaska have disappeared in recent years. This lake was used as a freshwater source for the village, forcing the community to find an alternative supply. This individual example shows us how communities living on frozen ground are directly affected by rapid changes in their lands," says researcher Tillmann Lübker.

ALEX is part of Arctic PASSION's Permafrost Service: a satellite imagery-derived map product showing changes in permafrost thaw with 30 m resolution on the pan-Arctic scale with the ability to reliably detect and assess regional disturbances such as coastal erosion, lake drainage, thermokarst lake expansion, infrastructure expansion, retrogressive thaw slumps, tundra fires, and fire scars, as well as the possibility to see change over time.

Map Tool: https://alex.awi.de/

Ingmar Nitze et al, Pan-Arctic Visualization of Landscape Change (2003-2022), Arctic PASSION Permafrost Service, PANGAEA (2024)
https://doi.pangaea.de/10.1594/PANGAEA.964814
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morganism

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Re: Permafrost general science thread
« Reply #228 on: February 10, 2024, 06:33:52 PM »
(ESA production, missed this when it came out. Found it when looking for
Jeffrey Combs Reads H. P. Lovecraft's Herbert West - Re-Animator- The One Nerd Showcase)

 What secrets lie beneath the frozen ground?     European Space Agency, ESA

Ice is without doubt one of the first casualties of climate change, but the effects of our warming world are not only limited to ice melting on Earth’s surface. Ground that has been frozen for thousands of years, called permafrost, is thawing – adding to the climate crisis and causing serious issues for local communities.

Scientists estimate that the world’s permafrost holds almost double the amount of carbon that is currently in the atmosphere. When permafrost warms and thaws, it releases methane and carbon dioxide, adding these greenhouse gases to the atmosphere and making global warming even worse.

While permafrost cannot be directly observed from space, a lot of different types of satellite data, along with ground measurements and modelling, allow scientists to paint a picture of permafrost ground conditions.


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morganism

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Re: Permafrost general science thread
« Reply #229 on: February 13, 2024, 09:09:06 PM »
Climate experts sound alarm over thriving plant life at Greenland ice sheet

Research shows there has been a near-quadrupling across Greenland of methane-producing wetlands

Significant areas of Greenland’s melted ice sheet are now producing vegetation, risking increased greenhouse gas emissions, rising sea levels and instability of the landscape.

A study has documented the change since the 1980s and shows that large areas of ice have been replaced with barren rock, wetlands and shrub growth, creating a change in environment.

Analysis of satellite records has shown that over the past three decades an estimated 11,000 sq miles of Greenland’s ice sheet and glaciers have melted, an area equivalent to the size of Albania and amounting to 1.6% of its total ice cover.

As ice has retreated, the amount of land with vegetation growing on it has increased by 33,774 sq miles, more than twice the area covered when the study began.

The findings show a near-quadrupling of wetlands across Greenland, which are a source of methane emissions.
(snip)
The scientists say warmer air temperatures are causing the ice to retreat and since the 1970s the region has been heating up at double the global average rate. On Greenland, the average annual air temperatures between 2007 and 2012 were 3C warmer than the average between 1979 and 2000.

According to the findings, there are signs that the increased vegetation is resulting in further ice loss.

Jonathan Carrivick, an Earth scientist at the University of Leeds and a co-author of the study, published in the journal Scientific Reports, said: “We have seen signs that the loss of ice is triggering other reactions which will result in further loss of ice and further ‘greening’ of Greenland, where shrinking ice exposes bare rock that is then colonised by tundra and eventually shrub.

“At the same time, water released from the melting ice is moving sediment and silt, and that eventually forms wetlands and fenlands.”


https://www.theguardian.com/world/2024/feb/13/flourishing-vegetation-greenland-ice-sheet-alarm-climate-crisis

Land cover changes across Greenland dominated by a doubling of vegetation in three decades

https://www.nature.com/articles/s41598-024-52124-1

Land cover responses to climate change must be quantified for understanding Arctic climate, managing Arctic water resources, maintaining the health and livelihoods of Arctic societies and for sustainable economic development. This need is especially pressing in Greenland, where climate changes are amongst the most pronounced of anywhere in the Arctic. Ice loss from the Greenland Ice Sheet and from glaciers and ice caps has increased since the 1980s and consequently the proglacial parts of Greenland have expanded rapidly. Here we determine proglacial land cover changes at 30 m spatial resolution across Greenland during the last three decades. Besides the vastly decreased ice cover (− 28,707 km2 ± 9767 km2), we find a doubling in total areal coverage of vegetation (111% ± 13%), a quadrupling in wetlands coverage (380% ± 29%), increased meltwater (15% ± 15%), decreased bare bedrock (− 16% ± 4%) and increased coverage of fine unconsolidated sediment (4% ± 13%). We identify that land cover change is strongly associated with the difference in the number of positive degree days, especially above 6 °C between the 1980s and the present day. Contrastingly, absolute temperature increase has a negligible association with land cover change. We explain that these land cover changes represent local rapid and intense geomorphological activity that has profound consequences for land surface albedo, greenhouse gas emissions, landscape stability and sediment delivery, and biogeochemical processes.
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FredBear

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Re: Permafrost general science thread
« Reply #230 on: February 17, 2024, 01:00:11 PM »
The BBC is reporting "Zombie" fires still smouldering from last year under the snow in Canada - ready to restart when the fire season restarts:-

https://www.bbc.co.uk/news/world-us-canada-68228943

(Not necessarily "permafrost" but parked it here?)

vox_mundi

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Re: Permafrost general science thread
« Reply #231 on: February 29, 2024, 10:40:00 PM »
Surprising Methane Discovery In Yukon Glaciers: 'Much More Widespread Than We Thought'
https://news.ku.dk/all_news/2024/02/young-researcher-makes-surprising-methane-discovery-in-yukon-glaciers-much-more-widespread-than-we-thought/
https://phys.org/news/2024-02-methane-discovery-yukon-glaciers-widespread.html

Global melting is prying the lid off methane stocks, the extent of which we do not know. A young researcher from the University of Copenhagen has discovered high concentrations of the powerful greenhouse gas in meltwater from three Canadian mountain glaciers, where it was not thought to exist—adding new unknowns to the understanding of methane emissions from Earth's glaciated regions.

Ph.D. student Sarah Elise Sapper is leading her first field expedition deep into the heart of the mountains of northwestern Canada. From the helicopter windows, her eyes fall on the jagged edge of the Donjek glacier: meltwater swirls out from beneath the ice like a whirlpool.

Soon after landing, it becomes apparent that Sarah has stumbled upon an unusual find on the first attempt. Seconds after starting up her portable methane analyzer it is clear that the air is enriched with methane and the culprit is soon found. Collecting a sample of meltwater, she measures concentrations of methane that far exceed expectations.

... We measured concentrations up to 250 times higher than those in our atmosphere," explains Sarah Elise Sapper of the University of Copenhagen's Department of Geosciences and Natural Resource Management.

The field party lifted off and continued to two more mountain glaciers, Kluane and Dusty. And after measuring the methane in the meltwater of each of those two glaciers, the preliminary finding turned out to be more than an anomaly. Here too, measurements showed high methane concentrations. Somewhere beneath the ice, there are previously unknown sources of the gas.

Christiansen, the research article's co-author, believes that the finding demonstrates the possibility of methane being present beneath many of the world's glaciers, ones that have thus far been written off.

"When we suddenly see that even mountain glaciers, which are small in comparison with an ice sheet, are able to form and emit methane, it expands our basic understanding of carbon cycling in extreme environments on the planet. The formation and release of methane under ice is more comprehensive and much more widespread than we thought," he says.

Until now, the prevailing view has been that methane in meltwater could only be found in oxygen- free environments under large masses of ice like the Greenland Ice Sheet.

"The meltwater from the surface of glaciers is oxygen-rich when it travels to the bottom of the ice. So we found it quite surprising that all this oxygen is used up somewhere along the way, so that oxygen-free environments form underneath these mountain glaciers. And even more surprising that it happens to such a degree, that microbes start producing methane and we can observe these high methane concentrations in the water flowing out at the glacier edges" states Sarah Elise Sapper.

"The three sites Sarah measured were randomly selected due to the availability of a research station and helicopter, yet methane was found in all three. In itself, that is a good reason to understand the area better. There's too much that we don't know, and the melting glaciers expose unknown environments that have remained hidden for thousands of years. In reality, no one knows how emissions will behave," says Jesper Riis Christiansen.
There are 3 classes of people: those who see. Those who see when they are shown. Those who do not see

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vox_mundi

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Re: Permafrost general science thread
« Reply #232 on: March 04, 2024, 07:23:32 PM »
Source or Sink? A Review of Permafrost's Role In the Carbon Cycle
https://phys.org/news/2024-03-source-permafrost-role-carbon.html



Scientists have researched the many factors affecting permafrost and its role in carbon cycling, including vegetation changes, periods of freeze and thaw, wildfire, and other disturbance events, for the past 20 years. In a new review paper published in the Journal of Geophysical Research: Biogeosciences, Treat, et al. looked at the breadth of knowledge on the topic to understand better how permafrost's change from carbon sink to carbon source in the Northern Hemisphere might affect climate goals.

The team concluded that terrestrial permafrost regions in the Northern Hemisphere remain a small net carbon dioxide sink overall. But wetland permafrost regions, especially in Eurasia, show high methane emissions. They also noted that there are lower carbon dioxide uptakes in higher latitudes, with the strongest sink located in western Canada.

Claire C. Treat et al, Permafrost Carbon: Progress on Understanding Stocks and Fluxes Across Northern Terrestrial Ecosystems, Journal of Geophysical Research: Biogeosciences (2024)
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023JG007638
There are 3 classes of people: those who see. Those who see when they are shown. Those who do not see

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kassy

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Re: Permafrost general science thread
« Reply #233 on: May 06, 2024, 09:40:53 PM »
Siberia's 'gateway to the underworld' is growing a staggering amount each year

The Batagay megaslump — a 3,250-foot-wide (990 meters) depression in the permafrost in the Russian Far East — is "actively growing" by a massive amount every year, scientists have found.

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.

...

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."

https://www.livescience.com/planet-earth/arctic/siberias-gateway-to-the-underworld-is-growing-a-staggering-amount-each-year
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morganism

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Re: Permafrost general science thread
« Reply #234 on: May 14, 2024, 10:58:56 PM »
(some new policy developments for Alaskans damaged by permafrost melt)

Thawing permafrost threatens Alaska's rural villages. And time is running out

Wilson Twitchell's house is sinking.

Twitchell and his wife, Bertha, are raising seven children in their small home in Kasigluk, a Yup'ik village of about 450 people in Southwest Alaska. These days, the little wooden house looks a bit like a giant picked it up and tossed it haphazardly back onto the tundra. One side is so sunken into the wet, marshy ground that when neighbors walk past the kitchen window, all the Twitchells can see are their knees.

"We try to jack up the house, but there's no solid," Twitchell said, sitting in his cozy kitchen, where supplies hang from the rafters and a pumpkin roll bakes in the oven. "Everything is turning into mush."

Even as it sinks, Twitchell loves this house. It's where he grew up. And he loves this village. Kasigluk sits in the heart of the Yukon-Kuskokwim Delta, a vast mosaic of lakes and rivers that spreads across the tundra and nurtures the food that is central to life in the village: salmon, whitefish, moose, and wild berries.

But the Twitchells aren't sure how much longer this house will be standing. Beneath the village, a layer of permafrost, once frozen year-round, has begun to thaw. Formerly solid ground has turned swampy. The local river is eroding its banks and encroaching on nearby homes.

"It's a losing battle," Wilson Twitchell said. "You can definitely see that the water is rising, the land is getting smaller."

Soon his family will have to move. And it's not clear where they will go.

Like the Twitchells, families in Alaska Native communities across the state are in a race against time. Human-caused climate change is warming the region and thawing the frozen mixture of ice, rock and dirt that underlies much of the landscape. That's undermining everything from homes and schools to water and sanitation systems.

Alaska Native communities have been raising the alarm for years, warning that thawing permafrost and erosion threaten their ability to stay on the land where their families have lived for generations. Now, officials say, the issue has reached a breaking point.

"We are experiencing widespread permafrost thaw, and that impacts buildings, roads, pipelines, the landscapes and Indigenous ways of life," said Jocelyn Fenton, director of programs with the Denali Commission, a federal agency responsible for some Alaska infrastructure.

"It is a critical issue that is here now."

A call for a new approach

Local officials and advocates say the federal government isn't doing enough to help, and it's time for a new approach.

A new report from a major nonprofit and the state of Alaska calls for an overhaul in how the federal government helps tribal communities that need to relocate some or all of their members because of climate change.

Funding to assist Alaska Native villages dealing with climate impacts has increased in recent years. But it's still far from enough — and the funding mechanisms can be too fragmented for small communities to access, said Jackie Qataliña Schaeffer, director of climate initiatives at the Alaska Native Tribal Health Consortium, which released the report.

The report estimates Alaska villages will need $80 million more per year over the next decade to keep their residents, like the Twitchells, safe.

To get help, villages often have to apply for separate federal programs to fund housing, roads, or sanitation. They end up competing with each other for the same funding opportunities. And in small communities, limited staffing makes it challenging to apply to a laundry list of federal grants.

"There's so many moving parts to these projects that it's overwhelming," Schaeffer said. "Then you add those layers and barriers, and it really, in some cases, is simply impossible."
(more)

https://text.npr.org/1242451927


The Unmet Needs of Environmentally Threatened Alaska Native Villages:

The purpose of this report is to help improve the effectiveness of federal and state government
support for Alaska communities to address climate and environmental threats to infrastructure from
erosion, flooding, and permafrost degradation. Legislative and programmatic changes are needed
to remove barriers faced by small rural communities and to create more effective and equitable
systems to deliver resources and services. The intended audience for this report is the U.S. Congress,
the White House, and federal and state agency leadership and program managers.

(200 page pdf)

https://www.anthc.org/wp-content/uploads/2024/01/Unmet_Needs_Report_22JAN24.pdf
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gerontocrat

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Re: Permafrost general science thread
« Reply #235 on: May 23, 2024, 12:11:18 AM »
An unwelcome piece of news, with perhaps severe consequences.

https://www.theguardian.com/us-news/article/2024/may/22/alaska-rivers-turning-orange
Quote
Alaskan rivers turning orange due to climate change, study finds

As frozen ground below the surface melts, exposed minerals such as iron are giving streams a rusty color that pose a risk to wildlife



Orange streams in the Brooks Range of northern Alaska. Photograph: Josh Koch/USGS

Dozens of rivers and streams in Alaska are turning rusty orange, a likely consequence of thawing permafrost, a new study finds.

The Arctic is the fastest-warming region in the globe, and as the frozen ground below the surface melts, minerals once locked away in that soil are now seeping into waterways.

“It’s an unforeseen impact of climate change that we’re seeing in some of the most pristine rivers in our country,” said Brett Poulin, study author and assistant professor of environmental toxicology at University of California Davis.

The permafrost thaw is exposing minerals to oxygen in a process known as weathering, which increases the acidity of the water and dissolves metals like zinc, copper, cadmium and iron – the most apparent metal that gives the rivers a rusty color visible even from satellite images. The study highlights the potential degradation of drinking water and risk to fisheries in the Arctic.

“When mixed with another river, it can actually make the metals even more potent [in its] impact to aquatic health,” Poulin said.

The phenomenon was first observed in 2018, when researchers noticed the milky orange appearance of the rivers across northern Alaska’s Brooks Range, a stark contrast to the crystal clear waters seen the year prior.

Within the year, a tributary of the Akillik river in Kobuk Valley national park saw the complete loss of two local fish species: the dolly varden and the slimy sculpin.

“Our data suggests that when the river turned orange, we saw a significant decrease in macroinvertebrates and biofilm on the bottom of the stream, which is essentially the base of the food web,” Poulin said of the rusting phenomenon. “It could be changing where fish are going to be able to live.”

The rusting is a seasonal phenomenon, occurring in the summer typically during July and August, when the soil is thawed the deepest. The researchers at the National Park Service, US Geological Survey and University of California Davis now want to better understand the long-term implications of the changing water chemistry in places with continuous permafrost, which includes Arctic regions such as Alaska, Canada, Russia and parts of Scandinavia.

“It’s an area that’s warming at least two to three times faster than the rest of the planet,” said Scott Zolkos, an Arctic scientist at Woodwell Climate Research Center who was not involved in the study. “So we can expect these types of effects to continue.”

The research group shared that they were working closely with tribal liaisons in Alaska to ensure local communities get accurate information on the developing phenomenon.
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Freegrass

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Re: Permafrost general science thread
« Reply #236 on: May 23, 2024, 01:38:27 AM »
As frozen ground below the surface melts, exposed minerals such as iron are giving streams a rusty color that pose a risk to wildlife
It looks like nature has started its own iron fertilization program.

And people were worried about the metals in Olivine...  ::)
This will become a serious disaster. I'm happy they will study it for a few years...

How many more studies do we need to tell us that we're all fucked?
Where is the outrage? Where is the follow-up to the Inconvenient Truth?
We're slowly boiling to death, and nobody cares...
When factual science is in conflict with our beliefs or traditions, we cuddle up in our own delusional fantasy where everything starts making sense again.

kassy

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Re: Permafrost general science thread
« Reply #237 on: May 23, 2024, 04:56:58 PM »
It looks like nature has started its own iron fertilization program.

Not really. Wrong place far away from the ocean target and it kills river life. It´s simply what happens when permafrost melts. It releases all the safely stored stuff. Some goes up into the air and some floats down rivers.

I think it´s important not to mix up concepts like this.
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Mr. Ä

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Re: Permafrost general science thread
« Reply #238 on: May 24, 2024, 07:57:05 AM »
As frozen ground below the surface melts, exposed minerals such as iron are giving streams a rusty color that pose a risk to wildlife
It looks like nature has started its own iron fertilization program.

Oceans next to river deltas don't need more fertilization. Or those other harmful metals. But it is a temporary problem. Once permafrost has melted and easily accessible metals are washed away, metal levels in rivers will return to normal. I bet it only takes a few decades.

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Re: Permafrost general science thread
« Reply #240 on: June 03, 2024, 01:43:10 PM »
New research shows soil microorganisms could produce additional greenhouse gas emissions from thawing permafrost

As the planet has warmed, scientists have long been concerned about the potential for harmful greenhouse gasses to seep out of thawing Arctic permafrost. Recent estimates suggest that by 2100 the amount of carbon dioxide and methane released from these perpetually frozen lands could be on par with emissions from large industrial countries. However, new research led by a team of microbiome scientists suggests those estimates might be too low.

...

Currently, these models assume that this community of microorganisms -- known as a microbiome -- will break down some types of carbon but not others. But the CSU-led work published this week in the journal Nature Microbiology provides new insight into how these microbes will behave once activated. The research demonstrates that the soil microbes embedded in the permafrost will go after a class of compounds previously thought to be untouchable under certain conditions: polyphenols.

"There were these pools of carbon -- say, donuts, pizza and chips -- and we were comfortable with the idea that microbes were going to use this stuff," said Bridget McGivern, a CSU postdoctoral researcher and the paper's first author. "But then there was this other stuff, spicy food; we didn't think the organisms liked spicy food. But what our work is showing is that actually there are organisms that are eating it, and so it's not going to just stay as carbon, it's going to be broken down."

More carbon being broken down by microbial respiration will produce additional greenhouse gas emissions. But this new finding has other implications, too. Some scientists had previously theorized that adding polyphenols to the thawing Arctic permafrost could potentially "turn off" these microorganisms altogether, effectively trapping a massive cache of potentially problematic carbon in the ground. The concept is known as the enzyme latch theory.

That no longer appears to be a viable option

...

McGivern started with a simple question. Scientists presumed that without oxygen, soil microbes could not break down polyphenols. Gut microbes, however, don't need oxygen to churn up the compound -- that's how humans extract healthy antioxidant benefits from polyphenol-rich substances such as chocolate and red wine. McGivern wondered why the process would be different in soils, a question that is particularly relevant to permafrost or waterlogged lands that contain little or no oxygen.

"The motivation for a lot of my Ph.D. was how could these two things exist?" McGivern said. "Organisms in our gut can breakdown polyphenols but organisms in the soil can't? The reality was that nobody in soils had really ever looked at it."

...

"What we found was that genes across 58 different polyphenol pathways were expressed," McGivern said. "So, we're saying not only can the microorganisms potentially do it, but they actually are, in the field, expressing the genes for this metabolism."

Still, more work is needed, McGivern said. They don't know what might constrain the process or the rates at which the metabolism is happening -- both important factors for eventually quantifying the amount of additional greenhouse gas emissions that could be released from permafrost.

Interesting.
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kiwichick16

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Re: Permafrost general science thread
« Reply #241 on: June 04, 2024, 05:08:35 AM »
@  kassy  .....interesting is one way of interpreting that new information  .......scary and signalling more heating in the pipeline could be another interpretation .....

kassy

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Re: Permafrost general science thread
« Reply #242 on: June 04, 2024, 04:46:46 PM »
They are not different. The interesting part is that they demonstrate there is source for extra carbon we thought would be preserved. So another good argument to preserve the permafrost.
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Re: Permafrost general science thread
« Reply #243 on: July 17, 2024, 09:19:40 AM »
Arctic permafrost: a linear threat, not a planetary tipping point

...

or many years, permafrost thaw has been seen as a ticking carbon time bomb, and one of nine proposed ‘tipping elements’, a term that describes large-scale components of the Earth system (such as the Amazon rainforest or the West Antarctic ice sheet) that may reach a tipping point – a threshold beyond which change is irreversible and self-perpetuating. However, a new study from polar researchers at the Alfred Wegener Institute, Germany, has found no evidence of a global climate tipping point in connection with permafrost.

According to climate scientist Jan Nitzbon, who led the research, the idea of permafrost being a global tipping element has long been controversial in the research community. He points to the 2008 study by climate change professor Timothy Lenton that first introduced the idea of tipping elements, and which put permafrost forward as a potential candidate. ‘Even back then,’ he says, ‘the researchers stated it would not fulfil their definition of a tipping element because the changes would be linear. But they still put it on the map and, somehow, it stuck there.’

Some time later, scientists identified that as permafrost thaws, bacteria in the soil speed up the decomposition of formerly frozen organic matter – dead animals, plants and microbes. As they feed on this matter, the bacteria release long-stored carbon into the atmosphere as carbon dioxide and methane. Scientists have suggested that once in the atmosphere, these greenhouse gases would further warm the planet, creating a strong positive feedback loop that thaws more permafrost, leading to rapid and widespread permafrost degradation.

‘This was something that the media picked up on – I’ve also seen it in educational material – and it has contributed to the idea of permafrost as a tipping element. But there is no evidence of self-amplifying internal processes that, from a certain degree of global warming, affect all permafrost and accelerate its thawing globally,’ says Nitzbon. ‘Moreover, the projected release of greenhouse gases wouldn’t lead to a global upsurge in warming by the end of the century. As such, portraying the permafrost as a global tipping element is misleading.’

That’s not to say that permafrost thaw isn’t a concern. ‘It’s definitely a concern,’ says Nitzbon, ‘and that’s also the point we want to make with this study.’ He explains that when talking about permafrost as a tipping element, there have often been suggestions of a corresponding temperature threshold. ‘That’s a problem, because it could lead to the misinterpretation that there’s some kind of a safety margin.’ Nitzbon emphasises that permafrost is already thawing, and at a rate that is increasing with every additional degree of global warming.

In their study, which compiled the available academic literature on the many processes that can influence and accelerate the thawing of permafrost – such as thermokarst lakes, which form deep, dark depressions that absorb more solar energy than the surrounding permafrost – and their own data analysis, Nitzbon and his colleagues also reveal that while there is no single global tipping point for permafrost, there are numerous local and regional ones that ‘tip’ at different times. As such, taking decisive action today is all the more important if our goal is to preserve as much permafrost as possible. Across the Arctic, permafrost is estimated to store about 1,460 billion to 1,600 billion tonnes of carbon – almost twice the amount that is currently in the atmosphere.

If global temperatures were to rise and fall again, then Arctic permafrost would reform. ‘So permafrost thaw itself isn’t irreversible,’ says Nitzbon. ‘But once the current permafrost deposits, which mostly formed during the last glacial period (the Pleistocene), have melted and the carbon stored within them has been released… that’s not something that can be reversed.’

https://geographical.co.uk/climate-change/arctic-permafrost-linear-threat

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vox_mundi

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Re: Permafrost general science thread
« Reply #244 on: August 09, 2024, 08:50:21 AM »
Researchers Find Unexpectedly Large Methane Source In Overlooked Landscape
https://phys.org/news/2024-08-unexpectedly-large-methane-source-overlooked.html



When Katey Walter Anthony heard rumors of methane, a potent greenhouse gas, ballooning under the lawns of fellow Fairbanks residents, she nearly didn't believe it.

"I ignored it for years because I thought 'I am a limnologist, methane is in lakes,'" she said.

But when a local reporter contacted Walter Anthony, who is a research professor at the Institute of Northern Engineering at University of Alaska Fairbanks, to inspect the waterbed-like ground at a nearby golf course, she started to pay attention. Like others in Fairbanks, they lit "turf bubbles" on fire and confirmed the presence of methane gas.

Then, when Walter Anthony looked at nearby sites, she was shocked that methane wasn't just coming out of a grassland. "I went through the forest, the birch trees and the spruce trees, and there was methane gas coming out of the ground in large, strong streams," she said.

With funding from the National Science Foundation, she and her colleagues launched a comprehensive survey of dryland ecosystems in Interior and Arctic Alaska to determine whether it was a one-off oddity or unforeseen concern.

Their study, published in the journal Nature Communications this July, reported that upland landscapes were releasing some of the highest methane emissions yet documented among northern terrestrial ecosystems. Even more, the methane consisted of carbon thousands of years older than what researchers had previously seen from upland environments.

"It's a totally different paradigm from the way anyone thinks about methane," Walter Anthony said.

The findings challenge current climate models, which predict that these environments will be an insignificant source of methane or even a sink as the Arctic warms.

She and colleagues identified 25 additional sites across Alaska's dry upland forests, grasslands and tundra and measured methane flux at over 1,200 locations year-round across three years. The sites encompassed areas with high silt and ice content in their soils and signs of permafrost thaw known as thermokarst mounds, where thawing ground ice causes some parts of the land to sink. This leaves behind an "egg carton" like pattern of conical hills and sunken trenches.

The researchers found all but three sites were emitting methane.

They found that unique formations known as taliks, where deep, expansive pockets of buried soil remain unfrozen year-round, were likely responsible for the elevated methane releases.



The research team emphasized that methane emissions are especially high for sites with Pleistocene-era Yedoma deposits. These soils contain large stocks of carbon that extend tens of meters below the ground surface. Walter Anthony suspects that their high silt content prevents oxygen from reaching deeply thawed soils in taliks, which in turn favors microbes that produce methane

Walter Anthony said it's these carbon-rich deposits that make their new discovery a global concern. Even though Yedoma soils only cover 3% of the permafrost region, they contain over 25% of the total carbon stored in northern permafrost soils.

The study also found through remote sensing and numerical modeling that thermokarst mounds are developing across the pan-Arctic Yedoma domain. Their taliks are projected to be formed extensively by the 22nd century with continued Arctic warming.

"Everywhere you have upland Yedoma that forms a talik, we can expect a strong source of methane, especially in the winter," Walter Anthony said.

"It means the permafrost carbon feedback is going to be a lot bigger this century than anybody thought," she said.

K. M. Walter Anthony et al, Upland Yedoma taliks are an unpredicted source of atmospheric methane, Nature Communications (2024)
https://www.nature.com/articles/s41467-024-50346-5

... observations indicate that talik (perennially thawed soils in permafrost) development in unsaturated Yedoma uplands leads to unexpectedly large methane emissions (35–78 mg m−2 d−1 summer, 150–180 mg m−2 d−1 winter). Upland Yedoma talik emissions were nearly three times higher annually than northern-wetland emissions on an areal basis. ... Contrary to current climate model predictions, these findings imply a positive and much larger permafrost-methane-climate feedback for upland Yedoma.
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morganism

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Re: Permafrost general science thread
« Reply #245 on: August 09, 2024, 07:13:10 PM »
(well, that is absolutely terrifying...no methane gun required now)
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vox_mundi

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Re: Permafrost general science thread
« Reply #246 on: August 13, 2024, 04:56:22 PM »
Arctic Ocean May Absorb Less CO₂ Than Projected Due to Coastal Erosion
https://phys.org/news/2024-08-arctic-ocean-absorb-co8322-due.html



As Earth warms, the Arctic Ocean's ability to absorb carbon dioxide from the atmosphere is waning due to melting permafrost and worsening coastal erosion, according to new research.

A study published Monday in the journal Nature Climate Change models the ways in which Arctic areas affected by permafrost erosion are releasing more carbon than they absorb. It found that by 2100, the effect may contribute to an annual increase in atmospheric carbon dioxide—a planet-heating gas—that is the equivalent of about 10% of all European car emissions in 2021.

The findings have worrisome implications about the ocean's vital ability to act as a carbon sink, or a place that removes greenhouse gases from the atmosphere, ... "For the first time, we can actually put a sign—maybe not a number but a sign—on the change in the Arctic Ocean's ability to take up CO2 from the atmosphere due to coastal erosion, and that sign is negative," Nielsen said.

The study builds on previous research that found erosion of coastal permafrost is accelerating, and could increase by a factor of 2 to 3 by 2100. That's largely because permafrost—or soil that was once permanently frozen—is beginning to thaw at a faster rate and for longer stretches of the year due to human-caused climate change, Nielsen said.

"During summer months along the Arctic coast, the soil is not frozen anymore, and so the ice is not there and there's open water," he said. "That makes the coast vulnerable to waves and storms which erode the coast—they mobilize this soil into the ocean."

The erosion could reduce the ocean's ability to absorb more than 14 million tons of CO2 per year by century's end, the researchers found. (A typical passenger car emits about 5 tons of CO2 per year.)

"We ran different simulations, and in all simulations, no matter how we represented this organic matter, the Arctic Ocean CO2 sink is reduced, so it's a pretty robust result," Nielsen said.

He noted that the Arctic is already warming much more quickly than the rest of the planet, at a rate 3 to 4 times faster than the global average. But his modeling found some acute "hot spots" of permafrost erosion, including Drew Point in Alaska, the Mackenzie River Delta in Canada and parts of Siberia, where local impacts include ocean acidification and adverse effects on coastal ecosystems.

... Though the modeling is focused on one region, McMonigal said outcomes in the Arctic will play an important role in Earth's future climate. The study projects that coastal permafrost erosion could exert a positive feedback loop that increases atmospheric CO2 by 1.1 million to 2.2 million tons per year for every degree Celsius, or 1.8 degrees Fahrenheit, of global warming.

David M. Nielsen et al, Reduced Arctic Ocean CO2 uptake due to coastal permafrost erosion, Nature Climate Change (2024)
https://www.nature.com/articles/s41558-024-02074-3
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kassy

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Re: Permafrost general science thread
« Reply #247 on: August 17, 2024, 09:43:17 PM »
A "Giant Mercury Bomb" Threatens To Go Off In North America's Arctic

A “giant mercury bomb” is ticking in the Arctic. As the world warms with climate change, mercury that’s been stored in the permafrost for thousands of years threatens to be set free into the environment, potentially wreaking havoc on wildlife and human life.

In a new study, scientists measured how much mercury could potentially seep into the ecosystem from thawed permafrost around the Yukon River.

To find out, they headed to two northern villages in Alaska’s Yukon River Basin – Beaver and Huslia – and took core samples from the top 3 meters (9.8 feet) of permafrost. They paired this with satellite data that shows how the Yukon River is changing course.

They found that significant amounts of mercury are released when riverbanks erode, but a smaller and more variable amount is redeposited as the rivers shift.

In conclusion, they found the mercury from the permafrost could pose an environmental and health threat to the 5 million people living in the Arctic zone.

“There could be this giant mercury bomb in the Arctic waiting to explode,” Josh West, study co-author and professor of Earth sciences and environmental studies at the University of Southern California - Dornsife, said in a statement.

Mercury is a metal that’s a liquid at room temperature, owing to its very low melting point. The element is highly toxic, acting as a neurotoxin by binding to and inhibiting the function of enzymes and proteins critical for nerve cell function.

It isn’t just found in science classrooms and thermometers. The metallic element circulates in small amounts through the natural world because it’s absorbed by plants, which then die and become part of the soil. It’s especially prolific in the Arctic, where the soil becomes frozen into permafrost, locking it away for generations.

“Because of the way it behaves chemically, a lot of mercury pollution ends up in the Arctic. Permafrost has accumulated so much mercury that it could dwarf the amount in the oceans, soils, atmosphere and biosphere combined,” said West.

It’s also a worrying problem for the northernmost parts of our planet because this region is warming up to four times faster than the global average and already feeling the sting of climate change,

The threat of mercury increases as the metal accumulates in the food chain, from plants to small creatures, eventually ending up in the fish and other animals that humans eat.

Since bioaccumulation is the problem, West explains that it’s not a problem similar to the Flint water crisis in Michigan. Nevertheless, the impact of mercury could be profound on communities living along the Yukon River and elsewhere in the Arctic.

“Decades of exposure, especially with increasing levels as more mercury is released, could take a huge toll on the environment and the health of those living in these areas,” Smith said.

The new study is published in the journal Environmental Research Letters.

https://www.iflscience.com/a-giant-mercury-bomb-threatens-to-go-off-in-north-americas-arctic-75595
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kassy

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Re: Permafrost general science thread
« Reply #248 on: September 08, 2024, 04:31:12 PM »
Scientists stunned at how rapidly 'Gateway to Hell' is growing and eating up enormous chunks of Earth

The crater has been growing unbelievably by 35 million cubic feet every year.


The Batagaika crater was first identified in classified satellite images in 1991. These images unveiled layers of permafrost frozen for 650,000 years. The melting permafrost released enormous quantities of methane gas, forming the crater. The process has accelerated due to climate change, and today, the crater emits methane and other greenhouse gases at an alarming rate, eroding chunks of the Earth continuously.

Understanding the Batagaika crater is a complex mystery. Explaining to HowStuffWorks, Roger Michaelides, an assistant professor of Earth and planetary sciences at Washington University in St. Louis, described that Batagaika isn’t actually a crater. That's a term reserved for bowl-shaped holes in the ground that are caused by the impact of meteorites, volcanic eruptions, or either a natural or man-made explosion of some sort, such as the Darvaza gas crater. Instead, Batagaika "is a retrogressive thaw slump, the largest in the world in fact," he noted.

...

Their findings revealed that the Batagaika 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. They mentioned in the study that the amount of ice and sediment lost from this megaslump is "exceptionally high" due to the sheer size of the depression, which stretched over 3,000 feet (990 m) wide as of 2023.

This depression was originally shaped by the cutting of forests around Batagaika during the Soviet era. It altered the thermal equilibrium of the area, leading to the formation of a down-slope gully. "The formation of this gully can lead to even more thaw of permafrost during subsequent summer seasons, which causes the gully to expand and grow larger. As larger surface areas of exposed permafrost are liable to thaw, this process accelerates and a megaslump can form," Michaelides said.

...

Accordingly, as Siberia becomes warmer due to climate change, Batagaika grows bigger and larger. "In some areas, the crater is expanding at a rate of tens of meters a year," Michaelides said. Although researchers already knew it was expanding, this is the first time they have come across the enormity of the changes in its size.

According to Live Science, a chunk equivalent to “more than 14 Great Pyramids of Giza” has melted off the megaslump since it collapsed. “There is enough potential to expand the Batagay megaslump over the adjacent valley which will most probably be absorbed in the next decade or two,” Nikita Tananaev, lead researcher at the Melnikov Permafrost Institute in Yakutsk, told Atlas Obscura. Tananaev added that this could mean trouble for the Batagay River in case the megaslump spills into it.

Although Batagaika continues to grow, researchers believe that there is a limit to how wide and deep it can go. Since the permafrost remaining inside the crater is only a few feet thick, the melt has already reached the bedrock at the bottom, and so cannot expand further, however, the sides can still expand to a point. “Only expansion along the margins and upslope is expected,” Kizyakov shared.

https://www.good.is/research-shows-gateway-to-hell-is-rapidly-growing-and-eating-up-enormous-chunks-of-earth-ex1
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