Arctic Sea Ice : Forum

Cryosphere => Permafrost => Topic started by: kassy on January 16, 2019, 02:42:56 PM

Title: Permafrost general science thread
Post by: kassy on January 16, 2019, 02:42:56 PM
I decided to make a new thread for general science on permafrost because the other threads are about either methane or snow cover or really specific issues.


The pace at which the world's permafrost soils are warming

As the new global comparative study conducted by the international permafrost network GTN-P shows, in all regions with permafrost soils the temperature of the frozen ground at a depth of more than 10 metres rose by an average of 0.3 degrees Celsius between 2007 and 2016 - in the Arctic and Antarctic, as well as the high mountain ranges of Europe and Central Asia. The effect was most pronounced in Siberia, where the temperature of the frozen soil rose by nearly 1 degree Celsius. The pioneering study has just been released in the online journal Nature Communications.


The complete dataset encompasses 154 boreholes, 123 of which allow conclusions to be drawn for an entire decade, while the remainder can be used to refine calculations on annual deviation. The results show that, in the ten years from 2007 to 2016, the temperature of the permafrost soil rose at 71 of the 123 measuring sites; in five of the boreholes, the permafrost was already thawing. In contrast, the soil temperature sank at 12 boreholes, e.g. at individual sites in eastern Canada, southern Eurasia and on the Antarctic Peninsula; at 40 boreholes, the temperature remained virtually unchanged.


The researchers observed the most dramatic warming in the Arctic: "There, in regions with more than 90 percent permafrost content, the soil temperature rose by an average of 0.30 degrees Celsius within ten years," reports first author Dr Boris Biskaborn, a member of the research group Polar Terrestrial Environmental Systems at the Potsdam facilities of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research. In northeast and northwest Siberia, the temperature increase at some boreholes was 0.90 degrees Celsius or even higher. For the sake of comparison: the air temperature in the respective regions rose by an average of 0.61 degrees Celsius in the same period.

Farther south, in Arctic regions with less than 90 percent permafrost, the frozen ground only warmed by 0.2 degrees Celsius on average. "In these regions there is more and more snowfall, which insulates the permafrost in two ways, following the igloo principle: in winter the snow protects the soil from extreme cold, which on average produces a warming effect. In spring it reflects the sunlight, and prevents the soil from being exposed to too much warmth, at least until the snow has completely melted away," Biskaborn explains.

Significant warming can also be seen in the permafrost regions of the high mountain ranges, and in the Antarctic. The temperature of the permanently frozen soils in the Alps, in the Himalayas and in the mountain ranges of the Nordic countries rose by an average of 0.19 degrees Celsius. In the shallow boreholes in the Antarctic, the researchers measured a rise of 0.37 degrees.

for full details:
Title: Re: Permafrost general science thread
Post by: Bernard on January 16, 2019, 11:35:54 PM
I just read the quoted article at
One thing I was wondering is if similar studies are conducted in other places than permafrost. We have measures of sea water temperatures at different depths, but the global warming should also be measured in mean temperatures of underground, at depths where the temperature is stable year-round (about 10-20m if what I read is correct), whether this underground is frozen or not.
This is a bit off-topic, please point me to an existing thread if any.

Meanwhile, I created one such topic,2548.0.html
Title: Re: Permafrost general science thread
Post by: wdmn on April 16, 2019, 02:09:13 AM
Warming Arctic permafrost releasing large amounts of potent greenhouse gas

A recent study shows that nitrous oxide emissions from thawing Alaskan permafrost are about twelve times higher than previously assumed. About one fourth of the Northern Hemisphere is covered in permafrost, which is thawing at an increasing rate. As temperatures increase, the peat releases more and more greenhouse gases. And, even though researchers are monitoring carbon dioxide and methane, no one seems to be watching the most potent greenhouse gas: nitrous oxide.
Title: Re: Permafrost general science thread
Post by: DaveHitz on April 16, 2019, 02:43:27 AM
A recent study shows that nitrous oxide emissions from thawing Alaskan permafrost are about twelve times higher than previously assumed.

This is clearly no laughing matter...
Title: Re: Permafrost general science thread
Post by: gerontocrat on April 23, 2019, 03:06:30 PM
A new study says the release of methane and carbon dioxide from thawing permafrost will accelerate global warming and add up to $70tn (£54tn) to the climate bill. Tried to find the article and failed. See summary from the guardian way down below or go to ...

But I did find instead that shows worrying increases in the temperature of permafrost all over the Arctic

Permafrost is warming at a global scale
Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007–2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. .....
Carbon release resulting from permafrost degradation will potentially impact the Earth’s climate system because large amounts of carbon previously locked in frozen organic matter will decompose into carbon dioxide and methane. This process is expected to augment global warming by 0.13–0.27 °C by 2100 and by up to 0.42 °C by 2300. Despite this, permafrost change is not yet adequately represented in most of the Earth System Models14 that are used for the IPCC projections for decision makers. One major reason for this was the absence of a standardized global data set of permafrost temperature observations for model validation.

Melting permafrost in Arctic will have $70tn climate impact - study
Study shows how destabilised natural systems will worsen man-made problem

Jonathan Watts Global environment editor

The release of methane and carbon dioxide from thawing permafrost will accelerate global warming and add up to $70tn (£54tn) to the world’s climate bill, according to the most advanced study yet of the economic consequences of a melting Arctic.

If nations fail to improve on their current Paris agreement commitments, this feedback mechanism combined with a loss of heat-deflecting white ice will cause a near 5% amplification of global warming and its associated costs, says the paper, which was published on Tuesday in Nature Communications.

The authors say their study is the first to calculate the economic impact of permafrost melt and reduced albedo – a measure of how much light that hits a surface is reflected without being absorbed – based on the most advanced computer models of what is likely to happen in the Arctic as temperatures rise. It shows how destabilised natural systems will worsen the problem caused by man-made emissions, making it more difficult and expensive to solve.

They assessed stocks of CO2 and methane trapped in the permafrost by using samples taken from a depth of three metres at multiple points across the Arctic. These were run through the world’s most advanced climate simulation software in the US and at the UK Met Office to predict how much gas will be released at different levels of warming. Even with supercomputers, the number crunching took weeks because the vast geography and complex climate interactions of the Arctic throw up multiple variables. The researchers then applied previous economic impact models to assess the likely costs.

Permafrost melt is the main concern. Greenhouse gases, which have been frozen below the soil for centuries, have already begun to escape at the current level of 1 degrees Celsius of global heating. So far the impact is small. Ten gigatonnes of CO2 have been released from the ice but this source of emissions will grow rapidly once temperatures rise beyond 1.5C.

On the current trajectory of at least 3C of warming by the end of the century, melting permafrost is expected to discharge 280 gigatonnes of carbon dioxide and 3 gigatonnes of methane, which has a climate effect that is 10 to 20 times stronger than CO2.

This would increase the global cost of destruction, adaptation and emissions reduction by $70tn between now and 2300. This is 10 times higher than the projected benefits from a melting Arctic, such as easier navigation for ships and access to minerals, says the paper.
Title: Re: Permafrost general science thread
Post by: Sleepy on April 23, 2019, 03:26:42 PM
^--> (
Title: Re: Permafrost general science thread
Post by: gerontocrat on April 23, 2019, 04:34:14 PM
^--> (
Thanks, Sleepy.
Title: Re: Permafrost general science thread
Post by: vox_mundi on May 03, 2019, 05:25:08 AM
Permafrost is Thawing in the Arctic So Fast Scientists are Losing Their Equipment

Permafrost in some areas of the Canadian Arctic is thawing so fast that it's gulping up the equipment left there to study it.

"The ground thaws and swallows it," said Merritt Turetsky, a University of Guelph biologist whose new research warns the rapid thaw could dramatically increase the amounts of greenhouse gases released from ancient plants and animals frozen within the tundra.

...  "We've put cameras in the ground, we've put temperature equipment in the ground, and it gets flooded. It often happens so fast we can't get out there and rescue it.

"We've lost dozens of field sites. We were collecting data on a forest and all of a sudden it's a lake."


Nearly one-fifth of Arctic permafrost is now vulnerable to rapid warming, Turetsky's paper suggests. Plenty of it is in Canada, such as in the lowlands south of Hudson Bay.

Soil analysis found those quickly thawing areas also contain the most carbon. Nearly 80 per cent of them hold at least 70 kilograms of carbon per cubic metre.

That suggests permafrost is likely to release up to 50 per cent more greenhouse gases than climate scientists have believed. As well, much of it will be released as methane, which is about 30 per cent more efficient at trapping heat than carbon dioxide.

Open Access: Merritt R. Turetsky et al. Permafrost collapse is accelerating carbon release (, Nature (2019)
Title: Re: Permafrost general science thread
Post by: vox_mundi on May 23, 2019, 01:59:44 PM
Widespread Permafrost Degradation Seen In High Arctic Terrain

A McGill-led study published recently in Environmental Research Letters presents close to 30 years of aerial surveys and extensive ground mapping of the Eureka Sound Lowlands area of Ellesmere and Axel Heiberg Islands located at approximately 80 °N. The research focuses on a particular landform (known as a retrogressive thaw slump) that develops as the ice within the permafrost melts and the land slips down in a horseshoe-shaped feature. The presence of these landforms is well documented in the low Arctic.

... "Our study suggests that the warming climate in the high Arctic, and more specifically the increases in summer air temperatures that we have seen in recent years, are initiating widespread changes in the landscape," says Melissa Ward Jones, the study's lead author and a Ph.D. candidate in McGill's Department of Geography.


The research team noted that:

- There has been a widespread development of retrogressive thaw slumps in high Arctic polar deserts over a short period, particularly during the unusually warm summers of 2011, 2012 and 2015;

- That the absence of vegetation and layers of organic soil in these polar deserts make permafrost in the area particularly vulnerable to increases in summer air temperatures;

- Despite its relatively short duration, the thaw season (which lasts for just 3-6 weeks a year) initially drives the development of slumps and their later expansion in size, as their headwall retreats; and

- Over a period of a few years after the initiation of slumps, study results suggest various factors related to terrain (e.g. slope) become more important than air temperature in maintaining active slumps

Open Access: Melissa K Ward Jones et al, Rapid initialization of retrogressive thaw slumps in the Canadian high Arctic and their response to climate and terrain factors (, Environmental Research Letters (2019)
Title: Re: Permafrost general science thread
Post by: Juan C. García on May 26, 2019, 06:24:11 AM
I haven’t followed the heat on land too much, but it seems that it is going to be pretty bad this year.
Title: Re: Permafrost general science thread
Post by: Shared Humanity on May 26, 2019, 04:05:33 PM
Going to start hanging out here as I feel permafrost is neglected when it comes to discussing the cryosphere.
Title: Re: Permafrost general science thread
Post by: Rod on June 11, 2019, 05:12:54 AM
I am sorry I can't post links from Twitter from my phone.  There might be a way but I can't figure out how.

That said, go check out Zack's link to this paper if you are interested in permafrost. They say "Observed maximum thaw depths at our sites are already exceeding those projected to occur by 2090 under RCP 4.5."

 Seems pretty important.  I would be interested in hearing you thoughts on the research.
Title: Re: Permafrost general science thread
Post by: kassy on June 11, 2019, 06:58:22 AM

This is a clickable version of the link:

Another hint that we are underestimating the damage we are doing...i am pretty sure that the anomalously warm summers will be the new normal.

Title: Re: Permafrost general science thread
Post by: Viggy on June 11, 2019, 07:26:57 AM
Glad this thread was started! I've long felt that the effects of permafrost collapse and and the rate at which it can happen have been grossly underestimated. This just came across my news feed today -

Arctic death spiral speeds up sixfold, driving coastal permafrost collapse (

They found that during a 40-day period in the summer of 2017, the coast had retreated a remarkable 47 feet — with daily rates of collapse sometimes exceeding 3 feet.

Think about how insane that rate of loss is!
Title: Re: Permafrost general science thread
Post by: kassy on June 12, 2019, 03:13:46 PM
Carbon dioxide sources from Alaska driven by increasing early winter respiration from Arctic tundra

We find that tundra ecosystems were a net source of CO2 to the atmosphere annually, with especially high rates of respiration during early winter (October through December). Long-term records at Barrow, AK, suggest that CO2 emission rates from North Slope tundra have increased during the October through December period by 73% ± 11% since 1975, and are correlated with rising summer temperatures. Together, these results imply increasing early winter respiration and net annual emission of CO2 in Alaska, in response to climate warming.

Linked in the article above. The data is from 2012 to 2014 but I thought I would add it here just to show how bad our baseline is.
Title: Re: Permafrost general science thread
Post by: Rod on June 15, 2019, 12:24:11 AM
If you are feeling down because of methane and CO2 releases from melting permafrost, maybe a little laughing gas will cheer you up?  :-\

No laughing matter

Title: Re: Permafrost general science thread
Post by: kassy on June 15, 2019, 05:30:10 PM
Thanks Rod.

Good article, not so good news. A couple of snippits copied below:

a paper published this month in the journal Atmospheric Chemistry and Physics shows that nitrous oxide emissions from thawing Alaskan permafrost are about 12 times higher than previously assumed. Since N2O traps heat nearly 300 times more efficiently than carbon dioxide does, this revelation could mean that the Arctic — and the global climate — are in more danger than we thought.

“The assumption is that these permafrost soils are so cold there wouldn’t be much microbial activity,” Wilkerson said. “Until 2009 there was no indication by any study whatsoever that emissions could actually be quite large in permafrost regions.”

the paper:

Title: Re: Permafrost general science thread
Post by: Tom_Mazanec on June 15, 2019, 08:37:39 PM
Permafrost melting 70 years early:
and and

EDIT: AGW thawing the landscape glue:
The permafrost nightmare:

Still more on 70 years early:
Title: Re: Permafrost general science thread
Post by: kassy on June 19, 2019, 02:04:58 PM
Short quote from the first of the three links above:

A new study published this week in the journal Geophysical Research Letters revealed that unusually warm summers in the Canadian High Arctic between 2003 and 2016 resulted in permafrost melt up to 240% higher than previous years.
Louise Farquharson, a researcher at the Permafrost Laboratory at the University of Alaska Fairbanks and the study's lead author, told the three areas of melting permafrost studied in remote northern Canada are believed to have been frozen for thousands of years.
“This change is unprecedented on this kind of time scale,” Farquharson said.
She noted that while scientists had predicted the permafrost wouldn't melt for another 70 years, those forecasts didn't take into account the unusually warm summers that have happened in recent years.
Title: Re: Permafrost general science thread
Post by: Ken Feldman on June 25, 2019, 09:56:48 PM
This study was published in 2016, it indicates that "observed short‐term temperature sensitivity from the Arctic will have little impact on the global atmospheric CH4 budget in the long term if future trajectories evolve with the same temperature sensitivity". (

No significant increase in long‐term CH4 emissions on North Slope of Alaska despite significant increase in air temperature

Colm Sweeney, Edward Dlugokencky, Charles E. Miller, Steven Wofsy, Anna Karion, Steve Dinardo


Continuous measurements of atmospheric methane (CH4) mole fractions measured by NOAA's Global Greenhouse Gas Reference Network in Barrow, AK (BRW), show strong enhancements above background values when winds come from the land sector from July to December from 1986 to 2015, indicating that emissions from arctic tundra continue through autumn and into early winter. Twenty‐nine years of measurements show little change in seasonal mean land sector CH4 enhancements, despite an increase in annual mean temperatures of 1.2 ± 0.8°C/decade (2σ). The record does reveal small increases in CH4 enhancements in November and December after 2010 due to increased late‐season emissions. The lack of significant long‐term trends suggests that more complex biogeochemical processes are counteracting the observed short‐term (monthly) temperature sensitivity of 5.0 ± 3.6 ppb CH4/°C. Our results suggest that even the observed short‐term temperature sensitivity from the Arctic will have little impact on the global atmospheric CH4 budget in the long term if future trajectories evolve with the same temperature sensitivity.
Title: Re: Permafrost general science thread
Post by: Ken Feldman on June 25, 2019, 10:01:26 PM
The following paper, published in 2019, indicates that changes to wetlands will have more of an impact on the global methane concentrations than the thawing permafrost. (

Anthropogenic and Natural Factors Affecting Trends in Atmospheric Methane in Barrow, Alaska

Christopher Lawrence 1 and Huiting Mao 2,*
1 Atmospheric Sciences Research Center, State University of New York University at Albany, Albany, NY 12203, USA
2 Department of Chemistry, State University of New York College of Environmental Science and Forestry, Syracuse, NY 13210, USA
* Author to whom correspondence should be addressed.

Received: 5 February 2019 / Accepted: 29 March 2019 / Published: 5 April 2019

Abstract: This study examined the long-term trends in Arctic ambient methane (CH4) mixing ratios over 1986–2014 and investigated their potential causes. Significant correlations between carbon monoxide (CO) and CH4 in Barrow, Alaska (r = −0.59, p = 0.007) and Alert, Canada (r = −0.62, p = 0.004) with the strongest correlations occurring in April (r = −0.81, p = 0.000, and r = −0.80, p = 0.000) suggest local to global anthropogenic contributions to ambient CH4 during the cold months. Backward trajectories indicate a significant influence (27% of total trajectories) of local emissions from the Prudhoe Bay Oil Field on ambient CH4 in Barrow in winter, and this influence was dominated by other factors in summer. The mean CH4 wetland emission flux in Barrow over 1986–2014 was estimated to be 0.008 ± 0.002 µg m−2 s−1 while in Tiksi, Russia it was 0.010 µg m−2 s−1 over 2012–2016, which is comparable to the lower end of measurements in the literature. Note that in Barrow, there was a decrease in wetland flux from 0.0083 ± 0.002 µg m−2 s−1 over 1986–1998 to 0.0077 ± 0.002 µg m−2 s−1 from 1999–2006 followed by an increase to 0.0081 ± 0.002 µg m−2 s−1 over 2007–2014. Although the difference between the three values is not statistically significant due to small sample size, it is indicative of possible warm season wetland emissions contributing to the zero-growth period. Strong support for this hypothesis is that these changes are consistent with a concurrent drop in summertime temperature possibly causing a decrease in wetland emissions over 1998–2006 based on the statistically significant correlations between temperature and CH4 during August through November (r ~ 0.36–0.56, p = ≤0.05). In a warming climate, permafrost thawing can increase CH4 wetland emissions and also decrease wetlands making it a complex problem, and, hence, further study is needed to better understand the mechanisms driving long-term trends in Arctic CH4.

. Summary

This study investigated factors affecting Arctic atmospheric CH4 in Barrow, Alaska along with comparison sites in Alert, Canada, Summit, Greenland, and Tiksi, Russia. During the winter, Barrow and Alert see a significant correlation between CO and CH4 concentrations, indicative of anthropogenic influences. Cluster Analysis of backward trajectories during the winter suggested transport of CH4 from the Eurasian Continent and significant contribution from the Prudhoe Bay Oil Field. The amplitude of the annual cycle of CH4 has decreased over time due to increasing summertime annual minimums indicating increasing wetland emissions of CH4. Wetland fluxes between May and July in Barrow and Tiksi were estimated to be 0.005 µg m−2 s−1 and 0.006 µg m−2 s−1, respectively, while fluxes between June and July were 0.011 µg m−2s−1 and 0.014 µg m−2s−1. These fluxes are near the lower end of the range of ones from in situ field measurement studies. Wetland emission fluxes were estimated to be 0.0083 µg m−2s−1 before, 0.0077 µg m−2s−1 during, and 0.0081 µg m−2s−1 after the CH4 growth rate plateau (1998–2006). Although the difference between these three periods is not statistically significant, it indicates that reduced wetland emissions in the Arctic linked to cooler temperature may have played a role in the CH4 plateau during 1998–2006. This hypothesis was supported by a correlation (r = 0.37–0.56, p = 0.05–0.00) between temperature and CH4 over August–November. As the planet continues to warm, global wetlands, including Arctic wetlands, are likely to play a growing role in increasing CH4 concentrations. It has been estimated that global wetland CH4 emissions could increase by 33–60% [55] or as high as 80–110% [56] by the year 2100. However, with the potential decrease of Arctic wetlands due to permafrost loss, CH4 emissions may decrease in the Arctic long term [33]. The complexity of how Arctic wetland emissions of CH4 would respond to a warming climate warrants further study.
Title: Re: Permafrost general science thread
Post by: longwalks1 on June 26, 2019, 03:48:45 PM
Although the paper above does not have many authors, it does appear close to the multi-authoured similar paper

No significant increase in long-term CH 4 emissions on North
Slope of Alaska despite significant increase in air temperature
Colm Sweeney 1,2 , Edward Dlugokencky 2 , Charles E. Miller 3 , Steven Wofsy 4 , Anna Karion 1,2,5 ,
Steve Dinardo 3 , Rachel Y.-W. Chang 6 , John B. Miller 2 , Lori Bruhwiler 2 , Andrew M. Crotwell 1,2 ,
Tim Newberger 1,2 , Kathryn McKain 1,2 , Robert S. Stone 7 , Sonja E. Wolter 1,2 , Patricia E. Lang 2 , and
Pieter Tans 2

 Geophys. Res. Lett., 43, doi:10.1002/2016GL069292.

I have not gone back to the original posts about this paper in the forum.       What struck me in the 2016 paper and is repeated here is the wide variability on numbers due to wind direction, especially from the drilling sites (Prudhoe Bay).

The 2016 study concluded with the need for more sampling sites  and more study, 2019, more study. 

However CARVE is no longer with us and much funding for study in Alaska has been carved out of the budget. 
Title: Re: Permafrost general science thread
Post by: kassy on June 26, 2019, 03:53:56 PM
Just a reminder there is an arctic methane thread so it's probably best to put the CH4 stuff there.,12.0.html

Title: Re: Permafrost general science thread
Post by: Stephan on June 30, 2019, 01:09:04 PM
Please find a new video by the "JUST HAVE A THINK" series on permafrost (focus on ESS shelf)
Title: Re: Permafrost general science thread
Post by: kassy on June 30, 2019, 05:13:48 PM
That one should go in the methane thread linked above since it is exactly on topic there.
Title: Re: Permafrost general science thread
Post by: vox_mundi on July 03, 2019, 04:58:09 PM
Scientists Find Thawing Permafrost Releasing Carbon at Higher Rates than Previously Thought

... "This study was novel because we used new methods to directly track the soil carbon losses, and they were much higher than we previously thought," Schuur said. "This suggests that not only is carbon being lost through greenhouse gases directly to the atmosphere but also dissolved in waters that flow through the soil and likely carried carbon into streams, leaves and rivers."   

... According to the study, 5 to 15 percent of the soil carbon held in the permafrost could be released into the atmosphere by the end of the century, using the original scenario. The modeling exercise the research team used to compare agreed with the observations but suggests that the loss rate could be twofold or more higher. (I.e. >10-30%)

César Plaza et al. Direct observation of permafrost degradation and rapid soil carbon loss in tundra (, Nature Geoscience (2019)
Title: Re: Permafrost general science thread
Post by: b_lumenkraft on July 03, 2019, 05:03:31 PM

In Germany we have that saying "Die Einschläge kommen näher", translates to 'the woofs are coming closer'.
Title: Re: Permafrost general science thread
Post by: vox_mundi on July 03, 2019, 05:35:09 PM
'Die Einschläge' Indeed! 

30% of 1.5 trillion tons (of C) doesn't leave much for us humans to muck around with.
Title: Re: Permafrost general science thread
Post by: jai mitchell on July 03, 2019, 05:56:21 PM
This 500 GtC is in addition to the carbon emitted under RCP 8.5 emissions scenario.
Title: Re: Permafrost general science thread
Post by: wdmn on July 03, 2019, 06:03:29 PM
This 500 GtC is in addition to the carbon emitted under RCP 8.5 emissions scenario.

And according to pricing recently referred to by James Hansen, 500GtC would cost about 200-400 trillion dollars to remove from the atmosphere.
Title: Re: Permafrost general science thread
Post by: vox_mundi on July 08, 2019, 10:52:57 PM
Rising Tundra Temperatures Create Worrying Changes in Microbial Communities

Rising temperatures in the tundra of the Earth's northern latitudes could affect microbial communities in ways likely to increase their production of greenhouse gases methane and carbon dioxide, a new study of experimentally warmed Alaskan soil suggests.

"We saw that microbial communities respond quite rapidly—within four or five years—to even modest levels of warming," said Kostas T. Konstantinidis, the paper's corresponding author and a professor in the School of Civil and Environmental Engineering and the School of Biological Sciences at the Georgia Institute of Technology.

"Microbial species and their genes involved in carbon dioxide and methane release increased their abundance in response to the warming treatment. We were surprised to see such a response to even mild warming."

Eric R. Johnston el al., "Responses of tundra soil microbial communities to half a decade of experimental warming at two critical depths," ( PNAS (2019).
Title: Re: Permafrost general science thread
Post by: Tom_Mazanec on July 16, 2019, 03:31:06 PM
Still more on the 70 years earlier than expected:
Title: Re: Permafrost general science thread
Post by: Rod on July 29, 2019, 05:25:09 AM
“More thawing weather . . . this summer than any in the past century.”  I’m not sure, but that sounds bad. 🤔
Title: Re: Permafrost general science thread
Post by: morganism on July 29, 2019, 09:30:55 AM
Pluto’s ocean is capped and insulated by gas hydrates

"Clathrate hydrates act as a thermal insulator, preventing the ocean from completely freezing while keeping the ice shell cold and immobile. The most likely clathrate guest gas is methane, derived from precursor bodies and/or cracking of organic materials in the hot rocky core. Nitrogen molecules initially contained and/or produced later in the core would probably not be trapped as clathrate hydrates, instead supplying the nitrogen-rich surface and atmosphere. The formation of a thin clathrate hydrate layer cap to a subsurface ocean may be an important generic mechanism to maintain long-lived subsurface oceans in relatively large but minimally heated icy satellites and Kuiper belt objects.
Title: Re: Permafrost general science thread
Post by: kassy on July 29, 2019, 05:52:58 PM
Could you move that last one into this subforums methane thread? Thx.,12.0.html
Title: Re: Permafrost general science thread
Post by: vox_mundi on August 01, 2019, 05:22:23 PM
Researchers Calculate Soil Freezing Depth from Satellite Data

A team of researchers from the Space Research Institute of the Russian Academy of Sciences (RAS), the Institute for Water and Environmental Problems of the Siberian Branch of RAS, and the Moscow Institute of Physics and Technology (MIPT) has proposed a way to determine soil freezing depth based on satellite microwave radiometry. The findings were published in Studying the Earth From Space, a Russian-language journal of RAS.

... "This method has many advantages: gathering data from large areas independently from solar lighting and atmospheric conditions, a high frequency of observation in the high latitudes, sensitivity to subterranean processes, and relative cheapness," said Associate Professor Vasiliy Tikhonov from the space physics department at MIPT, who is also a senior researcher at the Space Research Institute of RAS. "We tested the method's reliability on the Kulunda Plain, a vast steppe in the southeast of Russia's West Siberian Plain. To this end, we compared satellite microwave radiometry data with the actual soil parameters and climate indicators measured on location at weather stations."

Figure 1. Frozen soil layer thickness, as measured and calculated using the model. The digits 1 through 4 indicate four studied areas on the Kulunda Plain in Altai Krai, Russia. The black symbols correspond to directly measured values, and the red triangles stand for calculated values.

... It turned out that identical sets of satellite data may correspond to different soil freezing depths. The additional factors at play are soil moisture, salinity, and composition, which can all affect the soil's capacity for microwave emission. The researchers also found that one-time radiometric observations do not produce reliable results, because radio waves may reflect at the interface between the frozen and unfrozen soil.

The team accounted for these findings in their calculations, proposing a method that determines soil freezing depth with a high accuracy based on the data from the Soil Moisture and Ocean Salinity (SMOS) satellite. To remotely determine soil freezing depth, the researchers employed daily series of thermal emission measurements, along with their own emission model that incorporates soil characteristics. The time period considered in the study began with the date of freezing, defined as a spike in thermal radiation picked up by the satellite. It ended with the first thaw day, when the amount of thermal radiation dropped sharply.

Open Access: D. A. Boyarskii et al. On evaluation of depth of soil freezing based on SMOS satellite data (, Исследования Земли из Космоса (2019)


SMOS detects freezing soil as winter takes grip