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ArcticMelt2

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Re: Arctic Methane Release
« Reply #1050 on: June 26, 2019, 04:57:56 PM »
Extent of ice in the Laptev Sea today (NSDIC 4km data).

Ken Feldman

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Re: Arctic Methane Release
« Reply #1051 on: June 26, 2019, 06:30:29 PM »
From what i get from scientists who have worked in ESAS and elsewhere at the Byrd center agrees with consensus. An interesting titbit is that they are more worried about fossil carbon release (methane and CO2) from permafrost than buried methane hydrate.

But most of all they are worried about the world proceeding with BAU, much more than putative natural tipping points.

sidd



sidd & Ken
Your responses concern clathrate loss as opposed to the melting/leaking permafrost "cap" that S&S believe has caused the "Boiling Ocean" phenomena.


Ken
The fact that "boiling oceans" were witnessed and photographed precludes the possibility that these methane bubbles were "absorbed in the water column".
When a permafrost layer is hundreds or thousands of feet in depth, it may survive multiple melting events. Once "Boiling Oceans" are observed, it seems reasonable to assume that the cap has thinned, and that a broader collapse is possibly eminent.


While extreme endothermic reactions are inevitable as the CH4 changes phase, the same is not applicable to the CH4 simply capped over.


Your argument re. the exploitation of large fields reminds me of the Yamal field so recently opened. With sanctions in place & the low price for gas, I'm unsure that the Russians can afford a similar project, or that they have any need to explore additional sites at this time.


BAU is a problem that theoretically can be solved. The ESAS's possibly catastrophic out-gassing, if S&S are correct, is something that has been building since the oceans inundated the shelf as the last ice age waned. We may be speeding the process up a bit, but without another ice age in the near future, the out-gassing will occur.
Terry


Terry,

The thawing of the permafrost, even at the accelerated rates under bau scenarios, doesn't release enough methane at once to spike the temperatures.  The "methane time bomb" and "clathrate gun" are clearly related to sudden releases of large amounts of methane.  Take a look at the title of Shakhova and Semiltov's 2019 review paper, "Understanding the Permafrost–Hydrate System and Associated Methane Releases in the East Siberian Arctic Shelf".

Keep in mind that the permafrost is already melting and has been since the last ice age.  Here is what the IPCC AR5 Report stated about permafrost thaw in 2013 (with the preceding summary on human emissions included for comparison).  I have bolded the RCP8.5 scenario results for the comparison.

Quote
Taking climate and carbon cycle feedbacks into account, we
can quantify the fossil fuel emissions compatible with the
RCPs. Between 2012 and 2100, the RCP2.6, RCP4.5, RCP6.0, and
RCP8.5 scenarios imply cumulative compatible fossil fuel emissions
of 270 (140 to 410) PgC, 780 (595 to 1005) PgC, 1060 (840
to 1250) PgC and 1685 (1415 to 1910) PgC respectively (values
quoted to nearest 5 PgC, range derived from CMIP5 model results).
For RCP2.6, an average 50% (range 14 to 96%) emission reduction is
required by 2050 relative to 1990 levels. By the end of the 21st century,
about half of the models infer emissions slightly above zero, while the
other half infer a net removal of CO2 from the atmosphere. {6.4.3, Table
6.12, Figure 6.25}
There is high confidence that reductions in permafrost extent
due to warming will cause thawing of some currently frozen
carbon. However, there is low confidence on the magnitude of
carbon losses through CO2 and CH4 emissions to the atmosphere,
with a range from 50 to 250 PgC between 2000 and 2100 under the
RCP8.5 scenario
. The CMIP5 Earth System Models did not include
frozen carbon feedbacks. {6.4.3.4, Chapter 12}

And the "boiling oceans" you mention relate to carbon loss from seeps in the ocean floor.  These have been observed for years and there are numerous studies about how the gases transfer to the ocean as the bubbles rise.  In the case of thawing permafrost, there are also numerous studies showing that significant amounts of the methane are digested by microbes before the bubbles rise, so that gases in the bubbles are not methane.

jai mitchell

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Re: Arctic Methane Release
« Reply #1052 on: June 26, 2019, 06:38:20 PM »
Ken,

While the RCP 8.5 for CMIP5 shows between 50 and 250 PgC to be released by 2100, the CMIP5 models did not include any of this additional carbon in the atmosphere into their projections of temperature response.

in addition:  https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL082187
Climate change drives widespread and rapid thermokarst development in very cold permafrost in the Canadian High Arctic
First published: 10 June 2019

Quote
Abstract
Climate warming in regions of ice‐rich permafrost can result in widespread thermokarst development, which reconfigures the landscape and damages infrastructure. We present multi‐site time‐series observations which couple ground temperature measurements with thermokarst development in a region of very cold permafrost. In the Canadian High Arctic between 2003 and 2016, a series of anomalously warm summers caused mean thawing indices to be 150 – 240 % above the 1979‐2000 normal resulting in up to 90 cm of subsidence over the 12‐year observation period. Our data illustrate that despite low mean annual ground temperatures, very cold permafrost (<‐10°C) with massive ground ice close to the surface is highly vulnerable to rapid permafrost degradation and thermokarst development. We suggest that this is due to little thermal buffering from soil organic layers and near surface vegetation, and the presence of near surface ground ice. Observed maximum thaw depths at our sites are already exceeding those projected to occur by 2090 under RCP 4.5.

final note:

when you say,

Quote
there are also numerous studies showing that significant amounts of the methane are digested by microbes before the bubbles rise, so that gases in the bubbles are not methane.

The studies show some PORTION of the methane is digested, none of them showing levels greater than 80%.  Your assertion that 'therefore the bubbles are not methane' is so obviously incorrect that you appear to be a bald-faced liar.  This is why nobody likes you.
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ArcticMelt2

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Re: Arctic Methane Release
« Reply #1053 on: June 26, 2019, 07:24:18 PM »

Archimid

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Re: Arctic Methane Release
« Reply #1054 on: June 26, 2019, 08:24:57 PM »
I like Ken’s posts. They seem genuinely skeptic of alarmism and he often backs his skepticism with links and solid arguments. I’ve learned from him. Also he is doing a great job over at Solutions.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

jai mitchell

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Re: Arctic Methane Release
« Reply #1055 on: June 26, 2019, 09:10:22 PM »
I would like to learn more about his 'great work' however, he tends to make sweeping dismissive statements that are not factually based, like the idea that whatever those bubbles are they are not methane because most  (estimates are actually a range between 25% and 75% or so) of the methane is digested on the way up.   

That car cannot crash into that wall because the brakes removed most of the forward momentum. . .
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Ken Feldman

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Re: Arctic Methane Release
« Reply #1056 on: June 26, 2019, 10:06:20 PM »
I would like to learn more about his 'great work' however, he tends to make sweeping dismissive statements that are not factually based, like the idea that whatever those bubbles are they are not methane because most  (estimates are actually a range between 25% and 75% or so) of the methane is digested on the way up.   

That car cannot crash into that wall because the brakes removed most of the forward momentum. . .

It matters at what speed the car crashes into the wall.  At 5 mph, the paint might be scraped.  At 75 mph, the occupants of the vehicle are probably dead.

Catastrophists routinely ignore any evidence that contradicts with their highly improbable disaster scenarios.  They complain that "consensus scientists" ignore the threat.  Yet it's the catastrophists who ignore the science.

I spent a lot of time arguing with climate deniers in the past decade, so I have a lot of experience dealing with people who deny the climate science.  Catastrophists are basically a form of climate science deniers.

Ken Feldman

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Re: Arctic Methane Release
« Reply #1057 on: June 26, 2019, 10:13:15 PM »
This article shows that most of the methane release from subsea permafrost gets consumed as it goes through the unfrozen sediments above the subsea permafrost.  This implies that breakdown of the subsea permafrost is not the source for methane detected in bubbles that break the surface.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2014JG002862

Quote
Methane oxidation following submarine permafrost degradation: Measurements from a central Laptev Sea shelf borehole

PP Overduin, et. al. - ‎2015
 
Abstract
 

Submarine permafrost degradation has been invoked as a cause for recent observations of methane emissions from the seabed to the water column and atmosphere of the East Siberian shelf. Sediment drilled 52 m down from the sea ice in Buor Khaya Bay, central Laptev Sea revealed unfrozen sediment overlying ice‐bonded permafrost. Methane concentrations in the overlying unfrozen sediment were low (mean 20 µM) but higher in the underlying ice‐bonded submarine permafrost (mean 380 µM). In contrast, sulfate concentrations were substantially higher in the unfrozen sediment (mean 2.5 mM) than in the underlying submarine permafrost (mean 0.1 mM). Using deduced permafrost degradation rates, we calculate potential mean methane efflux from degrading permafrost of 120 mg m−2 yr−1 at this site. However, a drop of methane concentrations from 190 µM to 19 µM and a concomitant increase of methane δ13C from −63‰ to −35‰ directly above the ice‐bonded permafrost suggest that methane is effectively oxidized within the overlying unfrozen sediment before it reaches the water column. High rates of methane ebullition into the water column observed elsewhere are thus unlikely to have ice‐bonded permafrost as their source.


Archimid

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Re: Arctic Methane Release
« Reply #1058 on: June 27, 2019, 03:42:07 AM »

Catastrophists routinely ignore any evidence that contradicts with their highly improbable disaster scenarios.  They complain that "consensus scientists" ignore the threat.  Yet it's the catastrophists who ignore the science.


Sudden Arctic methane release is not "highly improbable". It is unlikely that enough methane is released so that global temperatures rise by a few degree in a few years.  It is likely that as arctic sea ice vanishes and the NH warms, more greenhouse gasses will be released, methane included. The more and faster it warms the more methane will be released, the more it will warm. It will warm really fast after the first BOE. Methane release must increase significantly, particularly local warming.

That is the simple truth. Will methane and warming spiral out of control after the first BOE? Unknown. It hasn't happened this fast anywhere on record. All scientists can do is study the fastest warming of the past, multiply it times ten and infer.

Granted their inferences are informed by the laws of physics, decades of rigorous studies, sweat and tears. One would be a fool to ignore what their models say. Sadly, there is no double blind experiment in climate science and we are dealing with the future unknown.

There is significant evidence suggesting the possibility of runaway methane emissions that would make our lives miserable. We shouldn't wait and find out. We should do everything possible to not find out if there is a methane bomb or not. We should act as if there is going to be one and avoid it at all cost.
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jai mitchell

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Re: Arctic Methane Release
« Reply #1059 on: June 27, 2019, 07:17:39 PM »
This article shows that most of the methane release from subsea permafrost gets consumed as it goes through the unfrozen sediments above the subsea permafrost.  This implies that breakdown of the subsea permafrost is not the source for methane detected in bubbles that break the surface.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2014JG002862

Quote
Methane oxidation following submarine permafrost degradation: Measurements from a central Laptev Sea shelf borehole

PP Overduin, et. al. - ‎2015
 
Abstract
 

Submarine permafrost degradation has been invoked as a cause for recent observations of methane emissions from the seabed to the water column and atmosphere of the East Siberian shelf. Sediment drilled 52 m down from the sea ice in Buor Khaya Bay, central Laptev Sea revealed unfrozen sediment overlying ice‐bonded permafrost. Methane concentrations in the overlying unfrozen sediment were low (mean 20 µM) but higher in the underlying ice‐bonded submarine permafrost (mean 380 µM). In contrast, sulfate concentrations were substantially higher in the unfrozen sediment (mean 2.5 mM) than in the underlying submarine permafrost (mean 0.1 mM). Using deduced permafrost degradation rates, we calculate potential mean methane efflux from degrading permafrost of 120 mg m−2 yr−1 at this site. However, a drop of methane concentrations from 190 µM to 19 µM and a concomitant increase of methane δ13C from −63‰ to −35‰ directly above the ice‐bonded permafrost suggest that methane is effectively oxidized within the overlying unfrozen sediment before it reaches the water column. High rates of methane ebullition into the water column observed elsewhere are thus unlikely to have ice‐bonded permafrost as their source.

my apologies Ken,  I was referring to the thermokarst studies and the bubbles from those sources in the water.  https://climate.nasa.gov/news/2785/unexpected-future-boost-of-methane-possible-from-arctic-permafrost/

The issue of thermokarst abrupt thawing is the current info that needs to be incorporated into the models.

I have not been too concerned about ESAS CH4 emissions since Semiletov and Shakova (I think in 2015) did their subsea ESAS carbon core sample survey where they determined that the LENA river sediment had very low carbon present.  Though long-term all bets are off depending on what kind of warming we get at toward the end of this century.

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morganism

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Re: Arctic Methane Release
« Reply #1060 on: June 27, 2019, 11:00:05 PM »
xpost from carbon capture:

It appears that injecting regular air content nitrogen into methane hydrates, along with CO2, creates a slow moving wave of carbon diox hydrates, releasing the methane to be captured.

"shows that injecting air and carbon dioxide into methane ice deposits buried beneath the Gulf of Mexico could unlock vast natural gas energy resources while helping fight climate change by trapping the carbon dioxide underground.

https://phys.org/news/2019-06-natural-gas-carbon-dioxide.html

Nitrogen-Driven Chromatographic Separation During Gas Injection into Hydrate-Bearing Sediments, Water Resources Research (2019). DOI: 10.1029/2018WR023414

pdf:
https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018WR023414

"In the paper, the authors showed that a process in which one type of molecule trapped in hydrate is exchanged for another (called guest molecule exchange) is a two-stage process and not a single, simultaneous process, as it was previously thought to be.

First, nitrogen breaks down the methane hydrate. Second, the carbon dioxide crystalizes into a slow-moving wave of carbon dioxide hydrate behind the escaping methane gas.

The computer simulations indicate that the process can be repeated with increasing concentrations of carbon dioxide until the reservoir becomes saturated. The authors said that unlike some methods of carbon storage, this provides a ready incentive for industry to begin storing carbon dioxide, a major driver of climate change."
« Last Edit: June 27, 2019, 11:21:57 PM by morganism »

morganism

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Re: Arctic Methane Release
« Reply #1061 on: June 27, 2019, 11:12:28 PM »
Just wanted to point out again, that the Ridiculously Resilient Ridge, the Four Corners stationary high, and the Iceland blocking high, are all pretty weird phenom.

The Four Corners high has not reappeared since the huge methane leaks from N New Mex/ S. Colorado have been imaged and possibly addressed.

If those stationary highs are indeed from leaks of methane to atmo, then it is likely that methane truly is making it to surface of ocean in large quantities.

edit: (As the Four Corners leak, was the largest in the Cont US.)

http://weatherwest.com/archives/5982

« Last Edit: June 27, 2019, 11:33:26 PM by morganism »

Ken Feldman

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Re: Arctic Methane Release
« Reply #1062 on: June 28, 2019, 01:09:42 AM »
This article shows that most of the methane release from subsea permafrost gets consumed as it goes through the unfrozen sediments above the subsea permafrost.  This implies that breakdown of the subsea permafrost is not the source for methane detected in bubbles that break the surface.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2014JG002862

Quote
Methane oxidation following submarine permafrost degradation: Measurements from a central Laptev Sea shelf borehole

PP Overduin, et. al. - ‎2015
 
Abstract
 

Submarine permafrost degradation has been invoked as a cause for recent observations of methane emissions from the seabed to the water column and atmosphere of the East Siberian shelf. Sediment drilled 52 m down from the sea ice in Buor Khaya Bay, central Laptev Sea revealed unfrozen sediment overlying ice‐bonded permafrost. Methane concentrations in the overlying unfrozen sediment were low (mean 20 µM) but higher in the underlying ice‐bonded submarine permafrost (mean 380 µM). In contrast, sulfate concentrations were substantially higher in the unfrozen sediment (mean 2.5 mM) than in the underlying submarine permafrost (mean 0.1 mM). Using deduced permafrost degradation rates, we calculate potential mean methane efflux from degrading permafrost of 120 mg m−2 yr−1 at this site. However, a drop of methane concentrations from 190 µM to 19 µM and a concomitant increase of methane δ13C from −63‰ to −35‰ directly above the ice‐bonded permafrost suggest that methane is effectively oxidized within the overlying unfrozen sediment before it reaches the water column. High rates of methane ebullition into the water column observed elsewhere are thus unlikely to have ice‐bonded permafrost as their source.

my apologies Ken,  I was referring to the thermokarst studies and the bubbles from those sources in the water.  https://climate.nasa.gov/news/2785/unexpected-future-boost-of-methane-possible-from-arctic-permafrost/

The issue of thermokarst abrupt thawing is the current info that needs to be incorporated into the models.

I have not been too concerned about ESAS CH4 emissions since Semiletov and Shakova (I think in 2015) did their subsea ESAS carbon core sample survey where they determined that the LENA river sediment had very low carbon present.  Though long-term all bets are off depending on what kind of warming we get at toward the end of this century.

No problem Jai.  I think I was responding to another poster with the paper about the unfrozen layers of subsea permafrost and how microbes consume the methane from the permafrost layers below. 

As to thermokarst lakes, there's new evidence that microbes can consume the methane produced by organic material at the bottom of the lake before it's released.  This paper published in April 2019 finds evidence that microbes consume a large portion of the methane produced in the lakes before it rises to the surface.  (Note that Walter Anthony, one of the authors on the paper you posted, is a co-author of this paper).

https://iopscience.iop.org/article/10.1088/2515-7620/ab1042/meta

Quote
First evidence for cold-adapted anaerobic oxidation of methane in deep sediments of thermokarst lakes

M Winkel1,2,4, A Sepulveda-Jauregui1,4,5,6, K Martinez-Cruz1,5, J K Heslop1,7, R Rijkers2, F Horn2, S Liebner2,3 and K M Walter Anthony1

 Published 3 April 2019 •   © 2019 The Author(s). Published by IOP Publishing Ltd
 Environmental Research Communications,  Volume 1,  Number 2


Abstract
 

Microbial decomposition of thawed permafrost carbon in thermokarst lakes leads to the release of ancient carbon as the greenhouse gas methane (CH4), yet potential mitigating processes are not understood. Here, we report δ 13C–CH4 signatures in the pore water of a thermokarst lake sediment core that points towards in situ occurrence of anaerobic oxidation of methane (AOM). Analysis of the microbial communities showed a natural enrichment in CH4-oxidizing archaeal communities that occur in sediment horizons at temperatures near 0 °C. These archaea also showed high rates of AOM in laboratory incubations. Calculation of the stable isotopes suggests that 41 to 83% of in situ dissolved CH4 is consumed anaerobically. Quantification of functional genes (mcrA) for anaerobic methanotrophic communities revealed up to 6.7 ± 0.7 × 105 copy numbers g−1 wet weight and showed similar abundances to bacterial 16S rRNA gene sequences in the sediment layers with the highest AOM rates. We conclude that these AOM communities are fueled by CH4 produced from permafrost organic matter degradation in the underlying sediments that represent the radially expanding permafrost thaw front beneath the lake. If these communities are widespread in thermokarst environments, they could have a major mitigating effect on the global CH4 emissions.

jai mitchell

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Re: Arctic Methane Release
« Reply #1063 on: June 28, 2019, 05:03:45 PM »
Ken,

Yes, that was the paper I referenced and took exception to your comment on ALL of the methane being digested in situ vs. some or most of it.  When you stated that the bubbles were not methane, I thought you were suggesting the thermokarst bubbles were not methane when the high end estimate is that only 41 to 83% of it becomes digested (and the rest moves to the atmosphere.  Since the methane release at the surface of these ponds has been directly measured, it does not follow that all the CH4 gets digested in these circumstances.  As warming continues and the rate of anaerobic digestion increases rapidly, the disassociation rates of total CH4 produced will go down as the production rates exceed decomposition.  Again, this is more of a concern when we reach arctic ice free conditions by june 21 summer solstice at around 2065 and regional warming during this period is greater than 8C above the DMI arctic average for that day in the historical record.
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Ken Feldman

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Re: Arctic Methane Release
« Reply #1064 on: June 28, 2019, 08:30:20 PM »
Ken,

Yes, that was the paper I referenced and took exception to your comment on ALL of the methane being digested in situ vs. some or most of it.  When you stated that the bubbles were not methane, I thought you were suggesting the thermokarst bubbles were not methane when the high end estimate is that only 41 to 83% of it becomes digested (and the rest moves to the atmosphere.  Since the methane release at the surface of these ponds has been directly measured, it does not follow that all the CH4 gets digested in these circumstances.  As warming continues and the rate of anaerobic digestion increases rapidly, the disassociation rates of total CH4 produced will go down as the production rates exceed decomposition.  Again, this is more of a concern when we reach arctic ice free conditions by june 21 summer solstice at around 2065 and regional warming during this period is greater than 8C above the DMI arctic average for that day in the historical record.

Jai,

I haven't meant to imply that there are no increased methane emissions due to warming.  I've been arguing that the increases in methane emissions are not likely to be so fast as to produce a massive spike in temperatures and set off a feedback cycle that will result in runaway warming. Many of the catastrophists just add up every new source of fossil fuels emissions from every news article or blog post they read and wail that it's too late to stop runaway warming.  The point of my posts is to demonstrate that it's not too late.

I think it's still possible to keep global temperature increases to around 2C if we can transition to a decarbonized economy.  If we stop producing fossil fuels (which seems likely by 2065 given the pace of installations of renewable energy power plants and the projections for the transition to electric vehicles), we can more than offset the increased methane emissions from the Arctic with reductions in human emissions of methane, and more importantly, CO2.

ArcticMelt2

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Re: Arctic Methane Release
« Reply #1065 on: June 30, 2019, 09:49:49 PM »
As expected, on Kotelny Island, June 2019 was on 4 degrees warmer than any other June.

Also, the past month took 4-6th place in terms of average temperature among any other months:

1) July 1991 +7.7С
2) August 2018 +6.3C
3) July 1997 +6.1С
4-6) July 1965 +5.9С
4-6) August 1971 +5.9С
4-6) June 2019 +5.9С

This means high chances that the summer of 2019 will be the worst for methane emissions from the Laptev Sea.

ArcticMelt2

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Re: Arctic Methane Release
« Reply #1066 on: July 01, 2019, 08:52:52 AM »
On Kotelny Island, the temperature rose again to +7 degrees Celsius.

The Extent of ice in the Laptev Sea still comes first.

The edge of the polynya reached the 80th parallel (Earlier, similar on July 1 was observed only in 2014).

https://sites.google.com/site/arcticseaicegraphs/concentration-maps/sic0701

prokaryotes

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Re: Arctic Methane Release
« Reply #1067 on: July 09, 2019, 02:35:52 AM »
New study, Direct observation of permafrost degradation and rapid soil carbon loss in tundra
https://www.nature.com/articles/s41561-019-0387-6

Quote
Evidence suggests that 5–15% of the vast pool of soil carbon stored in northern permafrost ecosystems could be emitted as greenhouse gases by 2100 under the current path of global warming.

However, direct measurements of changes in soil carbon remain scarce, largely because ground subsidence that occurs as the permafrost soils begin to thaw confounds the traditional quantification of carbon pools based on fixed depths or soil horizons.

This issue is overcome when carbon is quantified in relation to a fixed ash content, which uses the relatively stable mineral component of soil as a metric for pool comparisons through time. We applied this approach to directly measure soil carbon pool changes over five years in experimentally warmed and ambient tundra ecosystems at a site in Alaska where permafrost is degrading due to climate change.

We show a loss of soil carbon of 5.4% per year (95% confidence interval: 1.0, 9.5) across the site. Our results point to lateral hydrological export as a potential pathway for these surprisingly large losses. This research highlights the potential to make repeat soil carbon pool measurements at sentinel sites across the permafrost region, as this feedback to climate change may be occurring faster than previously thought.

Summary
Quote
“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.”
https://news.nau.edu/schuur-carbon-permafrost-study



Thawing permafrost affects plant and soils in tundra ecosystems, and ultimately the storage of carbon in permafrost soils. The surface of tundra subsides as ice in permafrost melts and drains. This can mask the loss of soil carbon through time that occurs as a result of soil microbial activity converting soil organic matter into greenhouse gases carbon dioxide and methane. Accounting for ground subsidence as a result of thaw revealed that substantial quantities of soil carbon were loss both directly to the atmosphere as carbon dioxide, but also dissolve in water that drained from this site. Soil carbon loss from permafrost ecosystems that ends up in the atmosphere at greenhouse gases can ultimately accelerate climate change
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Ken Feldman

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Re: Arctic Methane Release
« Reply #1068 on: July 09, 2019, 09:25:18 PM »
That won't help with the problem of double-counting carbon emissions.  This study from 2016 mentioned the flow of dissolved carbon from melting permafrost into Arctic Ocean, but didn't quantify it.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL071772

Quote
Double‐counting challenges the accuracy of high‐latitude methane inventories

Brett F. Thornton, Martin Wik, Patrick M. Crill 

First published: 04 December 2016

Abstract
 

Quantification of the present and future contribution to atmospheric methane (CH4) from lakes, wetlands, fluvial systems, and, potentially, coastal waters remains an important unfinished task for balancing the global CH4 budget. Discriminating between these sources is crucial, especially across climate‐sensitive Arctic and subarctic landscapes and waters. Yet basic underlying uncertainties remain, in such areas as total wetland area and definitions of wetlands, which can lead to conflation of wetlands and small ponds in regional studies. We discuss how in situ sampling choices, remote sensing limitations, and isotopic signature overlaps can lead to unintentional double‐counting of CH4 emissions and propose that this double‐counting can explain a pan‐Arctic bottom‐up estimate from published sources, 59.7 Tg yr−1 (range 36.9–89.4 Tg yr−1) greatly exceeding the most recent top‐down inverse modeled estimate of the pan‐Arctic CH4 budget (23 ± 5 Tg yr−1).

Quote
1 Introduction

At first glance, balancing the CH4 budget should be simple. Decades long records of atmospheric CH4 exist, and with a lifetime of less than 10 years in the atmosphere [Prather et al., 2012], we should be able to construct a box model where known CH4 sources minus known CH4 sinks equals the current atmospheric burden. Though the atmospheric burden is well known, detailed accounting of both sources and sinks remains a tremendous challenge [Kirschke et al., 2013], somewhat due to potentially large CH4 sources newly noted in the past 10 years. Many of these potential new sources are regional, and many lie in the Arctic where warming temperatures may be more favorable for production and release of CH4 from long‐stored permafrost carbon (C), potentially contributing to a permafrost C warming feedback [Schuur et al., 2015; Vonk et al., 2013]. It remains a goal to reconcile the top‐down Arctic CH4 budget (e.g., calculating backward from the amount of CH4 observed in the atmosphere to sources), with bottom‐up budgets (e.g., summing the CH4 sources and sinks to determine the atmospheric burden). We provide here an updated, but rough, bottom‐up inventory, based on published estimates of various categories of natural Arctic CH4 sources, in Table 1. Although we concentrate on the bottom‐up budget in our discussion here, the top‐down budget is not without issues. Top‐down inverse modeling estimates for the Arctic are limited by relatively few atmospheric measurements in the Arctic [Bruhwiler et al., 2014], tropospheric modeling capabilities [Houweling et al., 1999], and uncertainty surrounding the hydroxyl radical, the primary atmospheric sink for CH4 [Montzka et al., 2011]. But top‐down budgets are mass balanced by design, which is not the case for the bottom‐up sums of independent studies.


Table 1. Arctic CH4 Budget; Bottom‐Up Versus Top‐Down

                                                                      Tg y−1            Study

Bottom‐Up Estimates
Lakes and ponds > 50°N                                         16.5 ± 9.2         Wik et al. [2016b] 
Lakes and ponds > 60°N (bLake4Me model)              11.9                Tan and Zhuang [2015] 
Rivers and streams > 54°N                                        0.3                Bastviken et al. [2011] 
Rivers and streams > 54°N                                        7.5                Stanley et al. [2016] 
Reservoirs > 54°N                                                     1.2                Bastviken et al. [2011] 
Arctic Ocean + Beaufort and Chukchi Seas (<82°N)      2                  Kort et al. [2012] 
ESAS                                                                        2.9               Thornton et al. [2016] 
ESAS                                                                      17                  Shakhova et al. [2014] 
Wetlands > 60°N                                                      23.2               Zhang et al. [2004] 
Wetlands > 53.1°N (CarbonTracker prior model,
based on Bergamaschi et al. [2005])                         31                  Bruhwiler et al. [2014] 
Wetlands > 50°N (ORCHIDEE model)                         31 ± 5             Bousquet et al. [2011] 
Sources sum (minimum–maximum)                       59.7 (36.9–89.4)
 
Top‐Down Inverse Model Estimates
>60°N, all natural sources                                    23 ± 5        Bruhwiler et al. [2014] Saunois et al. [2016] 
ESAS                                                                       0–4.5              Berchet et al. [2016] 

a Recent bottom‐up estimates for various Arctic CH4 source flux strengths are sorted into categories of lakes and ponds, rivers and streams, reservoirs, Arctic Ocean, ESAS, and wetlands. Estimates are based on extrapolations of measurements, except for the three process models noted. Note that the latitude bands differ, which partly account for the ultimate bottom‐up uncertainty seen here. Arctic Ocean flux is from the reported 2 mg m−2 d−1 extrapolated over 10 × 106 km2 of seasonally ice‐free Arctic Ocean regions for 100 ice‐free days [Kort et al., 2012]. Rivers and streams high estimate is based on the Stanley et al. [2016] global fluvial flux database distributed into fluvial surface areas reported by Bastviken et al. [2011]. Sum uses averages of the all estimates per category. Minimum uses category low values and lower bound of the Wik et al. [2016b] lake estimates; maximum uses category high values and upper bounds of ORCHIDEE wetland model and the Wik et al. [2016b] lake estimates. Including subarctic and boreal wetlands from 45°N to 60°N would add 34 Tg yr−1 to the Zhang et al. [2004] wetland estimate.

Quote
There are a wide variety of potential sources of CH4 in the waters of the ESAS. As the ESAS was above sea level at the last glaciation, it contains substantial subsea permafrost and organic material originally formed and frozen subaerially [Dmitrenko et al., 2011]. Additionally, the Laptev and East Siberian Seas are strongly influenced by terrestrial organic carbon input from rivers, providing a modern source of C to the seas [Charkin et al., 2011; Semiletov et al., 2005]. Complicating matters further, the age of the carbon in the present day terrestrial organic matter source may be old or young, C released from thawing permafrost—or C in organic material produced in the annual cycle of plant growth. Coastal erosion of thawing permafrost shorelines provides yet another carbon input into the Arctic system [Lantuit et al., 2013]. All of these marine and shore processes might contribute C to the Arctic CH4 cycle.

kassy

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Re: Arctic Methane Release
« Reply #1069 on: July 09, 2019, 09:38:18 PM »
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,”

Guess no one double counted the new carbon?
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Ken Feldman

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Re: Arctic Methane Release
« Reply #1070 on: July 09, 2019, 10:13:02 PM »
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,”

Guess no one double counted the new carbon?

From the news release that was posted upthread:

Quote
Our results point to lateral hydrological export as a potential pathway for these surprisingly large losses. This research highlights the potential to make repeat soil carbon pool measurements at sentinel sites across the permafrost region, as this feedback to climate change may be occurring faster than previously thought.

The new methods to detect the carbon losses related to tracking how it flows out of the soil through the water.  That water ultimately winds up in rivers, lakes, wetlands or the Ocean, where it is currently counted (and as the study showed, potentially double-counted).



SteveMDFP

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Re: Arctic Methane Release
« Reply #1071 on: July 10, 2019, 05:23:34 PM »
Copied from the 2019 Melting season thread, where it risked clogging up that topic:
Could any of this anomalous warming in the ESS and Alaska be from localized methane emissions? How soon does methane contribute warming once released?

<Edit Neven: Ask questions like this one in the 'stupid' questions thread, or the methane thread.>
...

<Edit Neven: ... No, it shouldn't be discussed here, because this thread is for near-real time monitoring of conditions in the Arctic. If you can point to reliable near-real time data graphs or maps that have a direct influence on the outcome of this melting season, and that can be compared to previous years, please do so. If not, take it up in other threads.>
Understood, appreciated!

I can "point" to it indeed - the guys who did this neat animation (press "play" button in the bottom right corner; it takes a bit to load) seem to have plenty good data on the subject. And those fellows are quite reliable bunch. But for now i am unable to "compare to previous years" due to particularities of data retrieval they offer. But perhaps someone else can do it for us here?

And please allow me to just briefly answer Oscilidous' questions, as these answers can help more than just him, i'm sure. I promise i won't go any further on this topic, too.

1. yes, quite some of that high heat could well be caused by local (regional) methane emissions, since methane's local warming potential is ~1000 times higher than CO2 and as you can see from the 1st link i gave just above in this post, both Alaska and ESAS have significantly elevated methane levels presently.

2. once methane reaches athmosphere - it starts to contribute extra warming instantly, as surface always emits IR (sunny days more, cloudy days / nights less) and methane is rather dilute presently, means every molecule is pretty effective at adding extra greenhouse effect; some technical info about how it all works can be found here.

Thank you very much for that link.  This is the first methane mapping link I've seen since 2013.  I wish they offered a reanalysis map instead of a forecast map.  But at least the forecast likely shows current methane levels across the arctic on the first frame.  That link,again is:

Methane forecasts
https://atmosphere.copernicus.eu/charts/cams/methane-forecasts?facets=undefined&time=2019070600,69,2019070821&projection=classical_arctic&layer_name=composition_ch4_surface

For those of us concerned about the potential of the arctic seafloor to release large amounts of methane, my interpretation would be "no, the arctic seafloor is not a major emitter of methane as of today."  I suspect we might see substantial release as the ESAS area becomes denuded of ice and the shallow waters warm later in the season.  I plan to keep an eye on that.

Ken Feldman

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Re: Arctic Methane Release
« Reply #1072 on: July 11, 2019, 10:57:56 PM »
Copied from the 2019 Melting season thread, where it risked clogging up that topic:
Could any of this anomalous warming in the ESS and Alaska be from localized methane emissions? How soon does methane contribute warming once released?

<Edit Neven: Ask questions like this one in the 'stupid' questions thread, or the methane thread.>
...

<Edit Neven: ... No, it shouldn't be discussed here, because this thread is for near-real time monitoring of conditions in the Arctic. If you can point to reliable near-real time data graphs or maps that have a direct influence on the outcome of this melting season, and that can be compared to previous years, please do so. If not, take it up in other threads.>
Understood, appreciated!

I can "point" to it indeed - the guys who did this neat animation (press "play" button in the bottom right corner; it takes a bit to load) seem to have plenty good data on the subject. And those fellows are quite reliable bunch. But for now i am unable to "compare to previous years" due to particularities of data retrieval they offer. But perhaps someone else can do it for us here?

And please allow me to just briefly answer Oscilidous' questions, as these answers can help more than just him, i'm sure. I promise i won't go any further on this topic, too.

1. yes, quite some of that high heat could well be caused by local (regional) methane emissions, since methane's local warming potential is ~1000 times higher than CO2 and as you can see from the 1st link i gave just above in this post, both Alaska and ESAS have significantly elevated methane levels presently.

2. once methane reaches athmosphere - it starts to contribute extra warming instantly, as surface always emits IR (sunny days more, cloudy days / nights less) and methane is rather dilute presently, means every molecule is pretty effective at adding extra greenhouse effect; some technical info about how it all works can be found here.

Thank you very much for that link.  This is the first methane mapping link I've seen since 2013.  I wish they offered a reanalysis map instead of a forecast map.  But at least the forecast likely shows current methane levels across the arctic on the first frame.  That link,again is:

Methane forecasts
https://atmosphere.copernicus.eu/charts/cams/methane-forecasts?facets=undefined&time=2019070600,69,2019070821&projection=classical_arctic&layer_name=composition_ch4_surface

For those of us concerned about the potential of the arctic seafloor to release large amounts of methane, my interpretation would be "no, the arctic seafloor is not a major emitter of methane as of today."  I suspect we might see substantial release as the ESAS area becomes denuded of ice and the shallow waters warm later in the season.  I plan to keep an eye on that.

The global methane forecast for July 10 2019:

https://atmosphere.copernicus.eu/charts/cams/methane-forecasts?facets=undefined&time=2019071000,3,2019071003&projection=classical_global&layer_name=composition_ch4_surface





Compared to the global one day temperatures for July 11 2019:



Focusing just on China, it appears that a very high level of methane (China appears to have a large area of more than 10,000 ppb methane) doesn't necessarily lead to an immediate spike in temperatures (with normal to below normal temperatures in the areas with high methane).

jai mitchell

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Re: Arctic Methane Release
« Reply #1073 on: July 12, 2019, 12:04:03 AM »
I think it's still possible to keep global temperature increases to around 2C if we can transition to a decarbonized economy.  If we stop producing fossil fuels (which seems likely by 2065 given the pace of installations of renewable energy power plants and the projections for the transition to electric vehicles), we can more than offset the increased methane emissions from the Arctic with reductions in human emissions of methane, and more importantly, CO2.

Ken,

I am sorry but you are incorrect, the only way we stay below 2C is with massive amounts of global dimming geoengineering, combined with a comprehensive multi-decadal industrial atmospheric carbon removal program initiated on a global scale.

I do appreciate your attempt to mitigate (pun unintended) some of the doomsay assertions.  I am also of the opinion that we won't see a massive methane burst from the arctic until 2065 at the earliest but that the slowly increasing (and jump after June 21st ice free conditions) emissions from frozen soils, temperature forests, and, eventually southern ocean venting, will be enough to produce 2X CO2 emissions conditions by 2100 even if all emissions are halted today.
Haiku of Past Futures
My "burning embers"
are not tri-color bar graphs
+3C today

petm

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Re: Arctic Methane Release
« Reply #1074 on: July 12, 2019, 12:34:01 AM »
Renewable energy projections? Seems to me that renewable energy is barely making a dent and there's far more lip service than action. The US federal government, arguably the most important player,  doesn't even acknowledge that anthropogenic climate change exists...

https://ourworldindata.org/grapher/global-primary-energy

prokaryotes

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Re: Arctic Methane Release
« Reply #1075 on: July 13, 2019, 04:27:50 AM »
Made a new video. Soil layers of permafrost that scientists expected to remain frozen for at least 70 more years have already begun thawing.

The Current State of Arctic PERMAFROST THAW

CLIMATE STATE WEBSITE | YOUTUBE | USCREEN

Sebastian Jones

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Re: Arctic Methane Release
« Reply #1076 on: July 13, 2019, 05:09:12 AM »
Made a new video. Soil layers of permafrost that scientists expected to remain frozen for at least 70 more years have already begun thawing.

<SNIPPAGE>


Excellent video Prokaryotes! I live on the boundary of continuous/discontinuous permafrost; monitoring retrogressive thaw slumps and living with warm permafrost is everyday life here. There are permafrosts dated to 400K BP here- and they are thawing.

sidd

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Re: Arctic Methane Release
« Reply #1077 on: July 13, 2019, 08:45:09 AM »
Re: permafrost 400K BP thawing

Interesting, that's MIS11, probably hotter than Eemian. Where is this ?

sidd

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Re: Arctic Methane Release
« Reply #1078 on: July 13, 2019, 05:38:05 PM »
Ken, as long as the water that methane bubbles pass through contains significant dissolved oxygen, the process of bacterial oxidation of methane will continue. However, because methane oxidation consumes dissolved oxygen there is a rate limit on how much methane can be consumed. That limit is controlled by the rate of oxygen supply, minus other natural processes that consume oxygen, such as the oxidation of organic matter in river water inflows into the Siberian shelf.

Some of the catastrophists are clearly wrong, but you cannot correctly assume that all methane bubbles will continue to be oxidize as the rate of methane release increases. Global methane data published in the scientific literature shows that global methane levels are increasing again, but the Arctic is not a primary source of the increased emissions. So far, so good. However, we need to remember that there are physical-chemical limits on oxidation rates.

Sebastian Jones

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Re: Arctic Methane Release
« Reply #1079 on: July 13, 2019, 06:34:55 PM »
Re: permafrost 400K BP thawing

Interesting, that's MIS11, probably hotter than Eemian. Where is this ?

sidd

In the Klondike Goldfields south of Dawson City.
I did a quick search for verification and discovered that I was wrong about the ancient permafrost- it is "only" 200K. I'll try to dig up a better resource.
https://www.cbc.ca/news/technology/klondike-permafrost-lives-up-to-its-name-1.493800

Sebastian Jones

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Re: Arctic Methane Release
« Reply #1080 on: July 13, 2019, 07:47:10 PM »
Here they age some of the permafrost at 700K- although there is some scepticism and ice could have persisted through so many interglacials, the evidence seems credible. Not that it matters much, but I've met many of these researchers and Froese is conservative, not given to hyperbole.
Extract:
The relict ice wedge overlain by the Gold Run tephra represents the oldest ice known in North America and is evidence that permafrost has been a long-term component of the North American cyrosphere. Importantly, this finding demonstrates that permafrost has survived within the discontinuous permafrost zone since at least the early-Middle Pleistocene. This age range includes several glacial-interglacial cycles, including marine isotope stages 5e and 11, both considered to be longer and warmer than the present interglaciation

https://science.sciencemag.org/content/321/5896/1648

morganism

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Re: Arctic Methane Release
« Reply #1081 on: August 12, 2019, 12:20:36 AM »
undark.org

The Methane Detectives: On the Trail of a Global Warming Mystery

"Scientists continue to offer competing hypotheses to explain the global uptick, and there is no shortage of potential suspects.

Only three elements of the global methane budget are large enough to be plausible culprits: microbial emissions (from livestock, agriculture, and wetlands); fossil fuel emissions; and the chemical process by which methane is scrubbed from the atmosphere."

https://undark.org/article/methane-global-warming-climate-change-mystery/

think this was posted earlier, but a pdf link

Very Strong Atmospheric Methane Growth in the 4 Years
2014-2017: Implications for the Paris Agreement

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018GB006009

vox_mundi

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Re: Arctic Methane Release
« Reply #1082 on: August 30, 2019, 12:29:40 AM »
Changes in Ice Volume Control Seabed Methane Emissions
https://phys.org/news/2019-08-ice-volume-seabed-methane-emissions.html

Ice sheet dynamics of the past likely caused fault movements in the Earth's crust, resulting in seabed methane release in ~1200 m water depth offshore Svalbard, an archipelago in the Norwegian Arctic.

"Our results show similar patterns over the last two ice ages, from 160,000 years ago through today. The new data suggest a link between changing continental ice volumes and deep-sea methane emission in the Arctic," says Tobias Himmler, researcher at the Geological Survey of Norway (NGU) and principle author of the study.

"Seep carbonates serve as geological archives of past seabed methane emissions"

After measuring the amounts of radioactive isotopes uranium and thorium found in the seep carbonates, scientists at the British Geological Survey were able to calculate the ages of the carbonate pieces. This data reveals three separate 10,000- to 20,000-year long methane emission episodes over the last 160,000 years. Methane was released when thick ice sheets moved in to cover Svalbard and the Barents Sea area, and later after the ice diminished.

"During ice sheet growth, the extra weight of the ice presses the Earth's crust downward. Following the melting of the ice, the crust rises again. Our data indicate that methane off western Svalbard emanated from the seabed primarily when ice sheet movements activated faults. How much methane was emitted, however, we don't know," explains Himmler.

Previous research has shown that methane emissions have occurred consistently since the last ice age, beginning about 23,000 years ago. Scientists from NGU and CAGE have now managed to -literally- drill further back in time using the MARUM's MeBo70 sea floor drill rig. The drilled seep carbonate samples reveal that there have been at least two older methane emission episodes in the past, between about 160,000 to 133,000 years and 50,000 to 40,000 years ago.

Open Access: Tobias Himmler et al, A 160,000-year-old history of tectonically controlled methane seepage in the Arctic, Science Advances (2019)




“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

morganism

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Re: Arctic Methane Release
« Reply #1083 on: September 15, 2019, 12:46:06 AM »
Microorganisms reduce methane release from the ocean

june 19th

"Here we find the largest oxygen free area in the oceans - an area of more than 1 million square kilometers, where part of the water column is completely oxygen-free. This oxygen-free water contains methane.

Microorganisms remove 80 pct. of the methane produced"

The big question now is which microorganisms are at play and how? The researchers have got a hint that highly specialized bacteria and so-called archaea (bacterial-like organisms) are involved."

http://spaceref.com/news/viewpr.html?pid=54597

nanning

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Re: Arctic Methane Release
« Reply #1084 on: September 15, 2019, 05:42:13 AM »
^^
From the article:
Quote
What can we learn from the bacteria?

"Although there is a lot of energy in methane, methane as a molecule is difficult to activate and break apart, says Professor Thamdrup.

"Finding out how microorganisms do the job is not only important for understanding the process. In the long term, it may also potentially be of biotechnological value. Maybe it can help us convert methane into other useful products."

Univ. of S.Denmark says "What can we learn from the bacteria?" -> products & exploitation.

This is from the natural sciences no less. Behaving like corporations subsidised by us.
There probably are exceptions but I see in biotech and microbiology absolutely NO RESPECT for other lifeforms and ecosystems.

   Other lifeform = potential product.  Nefarious.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
   Simple: minimize your possessions and be free and kind    It's just a mindset.       Refugees welcome

vox_mundi

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Re: Arctic Methane Release
« Reply #1085 on: September 26, 2019, 09:17:43 PM »
Mysterious 'Pocket' of Underwater Gas Could Contain 50 Million Tons of CO2
https://www.livescience.com/amp/massive-underwater-gas-trough-mystery.html

New research from Japan reminds us, enormous, miles-wide reservoirs of greenhouse gases lurk in untouched pockets just below the seafloor.

In a study published Aug. 19 in the journal Geophysical Research Letters, a team of researchers discovered one such pocket at the bottom of the Okinawa Trough, a massive submarine basin sitting southwest of Japan where the Philippine Sea plate is slowly sinking below the Eurasian plate. Using seismic waves to map the trough's structure, the team found a huge gas pocket stretching at least 2.5 miles (4 kilometers) wide and potentially containing more than 100 million tons (90.7 million metric tons) of CO2, methane or some combination of the two.

... Pressure wave velocities slowed down significantly over a wide area in the middle part of the trough, indicating a massive gas pocket. The team estimated that the pocket's width, but were unable to calculate how deep or concentrated the reservoir was.

... If the gas in the undersea reservoir is mostly CO2, it could have an even greater impact on climate change. If the pocket were to pop and release 50 million tons (45 million metric tons) of CO2 into the air at once, it could have a measurable effect on CO2 concentrations in the atmosphere, and thus on climate change. If pockets like this one are a widespread feature at ocean rifts, as the researchers suspect they might be, then the potential consequences could be even more significant.

... Based on the flow of heat around the study area, the researchers think another possibility is that a low-permeability cap of methane hydrate--a methane-containing ice--acts as the lid.



Large Gas Reservoir Along the Rift Axis of a Continental Back‐Arc Basin Revealed by Automated Seismic Velocity Analysis in the Okinawa Trough. Kota Mukumoto, Takeshi Tsuji, Andri Hendriyana. Geophysical Research Letters

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL083065
“There are three classes of people: those who see. Those who see when they are shown. Those who do not see.” ― Leonardo da Vinci

Insensible before the wave so soon released by callous fate. Affected most, they understand the least, and understanding, when it comes, invariably arrives too late

Ken Feldman

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Re: Arctic Methane Release
« Reply #1086 on: October 02, 2019, 12:25:41 AM »
An update global emissions methane budget is available in the linked open-access pre-print for discussion paper.

https://climatehomes.unibe.ch/~joos/papers/saunois19essddis.pdf

Quote
The Global Methane Budget 2000-2017
Marielle Saunois, et.al. (2019)

Here's an excerpt from the lengthy abstract:

Quote
… For the 2008-2017 decade, global methane emissions are estimated by atmospheric inversions (top-down approach) to be 572 Tg CH4 yr-1 (range 538-593, corresponding to the minimum and maximum estimates of the ensemble), of which 357 Tg CH4 yr-1 or ~60% are attributed to anthropogenic sources (range 50-65%). This total emission is 27 Tg CH4 yr-1 larger than the value estimated for the period 2000-2009 and 24 Tg CH4 yr-1 larger than the one reported in the previous budget for the period 2003-2012 (Saunois et al. 2016). Since 2012, global CH4 emissions have been tracking the carbon intensive scenarios developed by the Intergovernmental Panel on Climate Change (Gidden et al., 2019). Bottom-up methods suggest larger global emissions (737 Tg CH4 yr-1, range 583-880) than top-down inversion methods, mostly because of larger estimated natural emissions from sources such as natural wetlands, other inland water systems, and geological sources. However the strength of the atmospheric constraints on the top-down budget, suggest that these bottom-up emissions are overestimated. The latitudinal distribution of atmospheric-based emissions indicates a predominance of tropical emissions (~65% of the global budget, <30°N) compared to mid (~30%, 30°N-60°N) and high northern latitudes (~4%, 60°N-90°N). Our analyses suggest that uncertainties associated with estimates of anthropogenic emissions are smaller than those of natural sources, with top-down inversions yielding larger uncertainties than bottom-up inventories and models. The most important source of uncertainty in the methane budget is attributable to natural emissions, especially those from wetlands and other inland waters. Some global source estimates are smaller compared to the previously published budgets (Saunois et al. 2016; Kirschke et al. 2013), particularly for vegetated wetland emissions that are lower by about 35 Tg CH4 yr-1 due to efforts to partition vegetated wetlands and inland waters. Emissions from geological sources are also found to be smaller by 7 Tg CH4 yr-1, and wild animals by 8 Tg CH4 yr-1.

...

The section of the paper dealing with methane release from the ESAS is on pages 40 and 41.  Here are some excerpts.

Quote
... For geological emissions, the most used value has long been 20 Tg CH4 yr-1, relying on expert knowledge and literature synthesis proposed in a workshop reported in Kvenvolden et al. (2001), the author of this study recognising that this was a first estimation and needs revision. Since then, oceanographic campaigns have been organized, especially to sample bubbling areas of active seafloor gas seep bubbling. For instance, Shakhova et al. (2010; 2014) infer 8-17 Tg CH4 yr-1 emissions just for the Eastern Siberian Arctic Shelf (ESAS), based on the extrapolation of numerous but local measurements, and possibly related to thawing subseabed permafrost (Shakhova et al., 2015). Because of the highly heterogeneous distribution of dissolved CH4 in coastal regions, where bubbles can most easily reach the atmosphere, extrapolation of in situ local measurements to the global scale can be hazardous and lead to biased global estimates. Indeed, using very precise and accurate continuous land shore-based atmospheric methane observations in the Arctic region, Berchet et al. (2016) found a range of emissions for ESAS of ~2.5 Tg CH4 yr-1 (range [0-5]), 4-8 times lower than Shakhova’s estimates. Such a reduction in ESAS emission estimate has also been inferred from oceanic observations by Thornton et al. (2016a) with a maximum sea-air CH4 flux of 2.9 Tg CH4 yr-1 for this region.
...

These recent results, based on different approaches, suggest that the current estimate of 20 Tg CH4 yr-1 is too large and needs revision.  Therefore, as discussed in Section 3.2.2, we report here a reduced range of 5-10 Tg CH4 yr-1 for marine geological emissions compared to the previous budget, with a mean value of 7 Tg CH4 yr-1.


kassy

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Re: Arctic Methane Release
« Reply #1087 on: October 07, 2019, 05:41:58 PM »
Methane Emission in the Russian Arctic

A group of scientific researchers has discovered a record methane emission coming from the eastern Siberian Sea, expedition organizer Tomsk Polytechnic University (TPU) said in a statement.

The scientists found concentrations of the greenhouse gas —  which can significantly influence the planet’s climate — up to nine times the global average.

“This is the most powerful gas fountain I've ever seen,” said Igor Semiletov, the head of the expedition and a TPU professor. “No one has ever recorded anything like this before."

https://www.themoscowtimes.com/2019/10/07/scientists-discover-record-methane-emission-in-the-russian-arctic-a67621

We add that at the point of the discovered gas fountain, whose area was four to five square meters, water sampling was organized from several horizons, as well as sampling of bottom sediments. Moreover, the scientists did not need special plastic cones that were prepared to collect methane. Water "boiling" with methane bubbles could be scooped up with buckets. Moreover, scientists pumped compressed gas into several cylinders directly from the “sip” body.

“This is the most powerful sip I've ever seen. It is manifested by an increase in methane concentration in air up to 16 ppm (millionths of a share), which is 9 times more than the average planetary values. No one has ever registered this before! ”,


A clearer quote from https://news.tpu.ru/news/2019/10/07/35335/
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vox_mundi

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Re: Arctic Methane Release
« Reply #1088 on: October 08, 2019, 07:04:44 PM »
Researchers Find Global Ocean Methane Emissions Dominated by Shallow Coastal Waters
https://phys.org/news/2019-10-global-ocean-methane-emissions-dominated.html

... In addition to contributing to a better understanding of the global methane budget, the research yielded two other interesting findings:

-First, very shallow coastal waters contribute around 50 percent of the total methane emissions from the ocean, despite making up only 5 percent of the ocean area. That's because methane can seep out of natural gas reservoirs along continental margins and can be produced biologically in anoxic (oxygen-depleted) sediments at the seafloor. In deep waters, methane is likely to be oxidized as it travels its long route from the seafloor to the atmosphere. But in shallow waters, there's a rapid route to the atmosphere and methane escapes before it is oxidized. Weber is currently collaborating with John Kessler, a professor of earth and environmental sciences at Rochester, to resolve the remaining uncertainties in coastal methane emissions by conducting research cruises and further developing machine learning models.

-Second, methane exhibits a spatial pattern very similar to that of phytoplankton abundance, which supports a controversial recent hypothesis that plankton produces methane in the surface ocean. Previously, scientists believed methane could only be produced in the anoxic conditions found at the bottom of the ocean. "Evidence is gradually accumulating to overturn that paradigm, and our paper adds an important piece," Weber says.

Open Access: Thomas Weber, Nicola A. Wiseman & Annette Kock, Global ocean methane emissions dominated by shallow coastal waters, Nature Communications, 2019
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Ken Feldman

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Re: Arctic Methane Release
« Reply #1089 on: October 08, 2019, 08:25:56 PM »
^^^
Thanks Vox.

Here's the abstract from that paper.

Quote
Abstract
Oceanic emissions represent a highly uncertain term in the natural atmospheric methane (CH4) budget, due to the sparse sampling of dissolved CH4 in the marine environment. Here we overcome this limitation by training machine-learning models to map the surface distribution of methane disequilibrium (∆CH4). Our approach yields a global diffusive CH4 flux of 2–6TgCH4yr−1 from the ocean to the atmosphere, after propagating uncertainties in ∆CH4 and gas transfer velocity. Combined with constraints on bubble-driven ebullitive fluxes, we place total oceanic CH4 emissions between 6–12TgCH4yr−1, narrowing the range adopted by recent atmospheric budgets (5–25TgCH4yr−1) by a factor of three. The global flux is dominated by shallow near-shore environments, where CH4 released from the seafloor can escape to the atmosphere before oxidation. In the open ocean, our models reveal a significant relationship between ∆CH4 and primary production that is consistent with hypothesized pathways of in situ methane production during organic matter cycling.

The total oceanic emissions of 6 - 12 TgCH4 per year seems to rule out the S&S estimate of 8 - 17 Tg from the ESAS alone.

kassy

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Re: Arctic Methane Release
« Reply #1090 on: October 09, 2019, 06:44:45 PM »
But Semilitov and Shakova based their work on measurements from the ESAS while the new research is looking at something else.

There are good reasons why so much of the methane has build up in the ESAS. For details see:
https://www.mdpi.com/2076-3263/9/6/251/htm

Since the new research is not a new theory but rather an attempt at a better understanding of global ocean methane emissions it does not rule out S&S. It does not ´see´ the special circumstances below the ESAS describe in the link above because it looks at measurements made at sea only. 

Of course there is only 2 datapoints from S&S in there.

As they write in the link above:
The ESAS is the region of the WO where ˃80% of the world’s predicted subsea permafrost and associated permafrost-related hydrates exist.

From which we can then conclude the it is woefully undersampled. As you can see a few posts up they are taking new measurements right now.

I don´t think you can claim Weber et al rule out the ESAS emissions because that is not actually what they study.

As you can read in S&S there are good local reasons why the ESAS might be set up for these huge emissions. It is land permafrost that drowned later which makes its properties different from normal seabed methane deposits which formed in place.

It also has been melting for 12000 years with an acceleration in the last 30 years.

Subsea permafrost has been subjected to additional warming induced by sea water; in the ESAS, sea water is much warmer than air (mean annual air temperature of −10 °C vs. mean annual sea water temperature of −1 °C). Consequently, the subsea permafrost has warmed by up to 17 °C during the last 12 kyrs 

Based on results of the first comprehensive scientific re-drilling, it was shown that subsea permafrost in the near-shore area of the ESAS has exhibited downward ice-bonded permafrost table (IBPT) movement of ~14 cm y−1 during the last 30 years vs. ~6 cm y−1 in earlier years since inundation [22]. These rates indicate significant enhancement of the permafrost disintegration process during the last three decades.

*

We should always have aimed for max 1 C global to stop things like the current ESAS destabilization.

How bad is it going to be?

We don´t know but the only thing that is going to stop the proces is stopping the warming and actually cooling the planet.

“This is the most powerful sip I've ever seen. It is manifested by an increase in methane concentration in air up to 16 ppm (millionths of a share), which is 9 times more than the average planetary values. No one has ever registered this before! ”,

That is now while our governments are happy to pledge to something and then do nothing.

And nothing in Weber et al changes anything about that either.
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AngelaBasset1582

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Re: Arctic Methane Release
« Reply #1091 on: October 10, 2019, 08:21:25 AM »
Why is it that when there is news coverage of the ESAS, 9 times out of 10 its because Semilitov said something dramatic.

I know why people like to cite them, because there results conform to peoples preconceived notions of climate doom. But we've had multiple scientists look at the ESAS using both similar and more complex methods and have come back with radically different answers. Replication is an important part of science, and if others cant replicate your work, then you shouldn't be surprised when your new "discoveries" and taken with healthy doses of skepticism. 

TerryM

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Re: Arctic Methane Release
« Reply #1092 on: October 11, 2019, 02:33:59 AM »
Until others are willing or able to spend the months at sea that are required, replication will prove difficult.
Terry

kassy

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Re: Arctic Methane Release
« Reply #1093 on: October 12, 2019, 04:37:04 PM »
Any links to research relating to non russian (or non S&S) methane research cruises there?

And links to the work of ´multiple scientists look at the ESAS using both similar and more complex methods and have come back with radically different answers.´?

It would be interesting to contrast those just to see what kind of emissions we can expect as a lower bound.

Outside of replication we have things like the #1087 record size plumes. Something you could have expected in this starkly warming world.

I wonder if the more complex methods reproduce them...
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Ken Feldman

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Re: Arctic Methane Release
« Reply #1094 on: October 15, 2019, 07:25:10 PM »
Any links to research relating to non russian (or non S&S) methane research cruises there?

And links to the work of ´multiple scientists look at the ESAS using both similar and more complex methods and have come back with radically different answers.´?

It would be interesting to contrast those just to see what kind of emissions we can expect as a lower bound.

Outside of replication we have things like the #1087 record size plumes. Something you could have expected in this starkly warming world.

I wonder if the more complex methods reproduce them...

Here's a link to the Thornton et. al 2016 paper about their 2014 cruise in the same area that S&S covered.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL068977

Quote
Abstract
The Laptev and East Siberian Seas have been proposed as a substantial source of methane (CH4) to the atmosphere. During summer 2014, we made unique high‐resolution simultaneous measurements of CH4 in the atmosphere above, and surface waters of, the Laptev and East Siberian Seas. Turbulence‐driven sea‐air fluxes along the ship's track were derived from these observations; an average diffusive flux of 2.99 mg m−2 d−1 was calculated for the Laptev Sea and for the ice‐free portions of the western East Siberian Sea, 3.80 mg m−2 d−1. Although seafloor bubble plumes were observed at two locations in the study area, our calculations suggest that regionally, turbulence‐driven diffusive flux alone accounts for the observed atmospheric CH4 enhancements, with only a local, limited role for bubble fluxes, in contrast to earlier reports. CH4 in subice seawater in certain areas suggests that a short‐lived flux also occurs annually at ice‐out.

Also, if there were persistent methane leaks in the amount of those hyped by S&S recently, the methane would drift to the observation sites around the Arctic.  There's a paper that looked for increased methane concentrations due to those types of emissions from the ESAS that was published in 2016.

https://www.atmos-chem-phys.net/16/4147/2016/acp-16-4147-2016.pdf

Quote
Atmospheric constraints on the methane emissions from the East Siberian Shelf

Quote
Abstract. Subsea permafrost and hydrates in the East Siberian Arctic Shelf (ESAS) constitute a substantial carbon pool, and a potentially large source of methane to the atmosphere. Previous studies based on interpolated oceanographic campaigns estimated atmospheric emissions from this area at 8–17TgCH4 yr−1. Here, we propose insights based on atmospheric observations to evaluate these estimates. The comparison of high-resolution simulations of atmospheric methane mole fractions to continuous methane observations during the whole year 2012 confirms the high variability and heterogeneity of the methane releases from ESAS. A reference scenario with ESAS emissions of 8TgCH4 yr−1, in the lower part of previously estimated emissions, is found to largely overestimate atmospheric observations in winter, likely related to overestimated methane leakage through sea ice. In contrast, in summer, simulations are more consistent with observations. Based on a comprehensive statistical analysis of the observations and of the simulations, annual methane emissions from ESAS are estimated to range from 0.0 to 4.5TgCH4 yr−1. Isotopic observations suggest a biogenic origin (either terrestrial or marine) of the methane in air masses originating from ESAS during late summer 2008 and 2009.

Note that this paper confirmed the S&S estimates for summer emissions, but found that the winter emissions were far less than those assumed by S&S.

The stories about the recent large plume of methane measured by S&S are mostly hype.  We've seen other stories about methane bubbling up in the past, this is the first time they've been measured while actually active.  There are many pingo-like features on both land in the Arctic (the famous Yamal methane craters are an example) and below the sea.  Here's a paper describing the sub-sea pingo like features.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2015JF003467

Quote
Methane release from pingo‐like features across the South Kara Sea shelf, an area of thawing offshore permafrost

Quote
Abstract
The Holocene marine transgression starting at ~19 ka flooded the Arctic shelves driving extensive thawing of terrestrial permafrost. It thereby promoted methanogenesis within sediments, the dissociation of gas hydrates, and the release of formerly trapped gas, with the accumulation in pressure of released methane eventually triggering blowouts through weakened zones in the overlying and thinned permafrost. Here we present a range of geophysical and chemical scenarios for the formation of pingo‐like formations (PLFs) leading to potential blowouts. Specifically, we report on methane anomalies from the South Kara Sea shelf focusing on two PLFs imaged from high‐resolution seismic records. A variety of geochemical methods are applied to study concentrations and types of gas, its character, and genesis. PLF 1 demonstrates ubiquitously low‐methane concentrations (14.2–55.3 ppm) that are likely due to partly unfrozen sediments with an ice‐saturated internal core reaching close to the seafloor. In contrast, PLF 2 reveals anomalously high‐methane concentrations of >120,000 ppm where frozen sediments are completely absent. The methane in all recovered samples is of microbial and not of thermogenic origin from deep hydrocarbon sources. However, the relatively low organic matter content (0.52–1.69%) of seafloor sediments restricts extensive in situ methane production. As a consequence, we hypothesize that the high‐methane concentrations at PLF 2 are due to microbial methane production and migration from a deeper source.

David Archer, an expert in global methane sources, debunked hype about the Siberian craters years ago at Real Climate.

http://www.realclimate.org/index.php/archives/2014/08/how-much-methane-came-out-of-that-hole-in-siberia/comment-page-3/

Quote
Siberia has explosion holes in it that smell like methane, and there are newly found bubbles of methane in the Arctic Ocean. As a result, journalists are contacting me assuming that the Arctic Methane Apocalypse has begun. However, as a climate scientist I remain much more concerned about the fossil fuel industry than I am about Arctic methane. Short answer: It would take about 20,000,000 such eruptions within a few years to generate the standard Arctic Methane Apocalypse that people have been talking about. Here’s where that statement comes from:
How much methane emission is “a lot”? The yardstick here comes from Natalie Shakhova, an Arctic methane oceanographer and modeler at the University of Fairbanks. She proposed that 50 Gton of methane (a gigaton is 1015 grams) might erupt from the Arctic on a short time scale Shakhova (2010). Let’s call this a “Shakhova” event. There would be significant short-term climate disruption from a Shakhova event, with economic consequences explored by Whiteman et al Whiteman et al (2013). The radiative forcing right after the release would be similar to that from fossil fuel CO2 by the end of the century, but subsiding quickly rather than continuing to grow as business-as-usual CO2 does.

Quote
If the bubble was pure methane, it would have contained about … wait for it … 0.000003 Gtons of methane. In other words, building a Shakhova event from these explosions would take approximately 20,000,000 explosions, all within a few years, or else the climate impact of the methane would be muted by the lifetime effect.

There have been many studies (by both Russian and non-Russian scientists) into methane emissions from the Arctic seafloor.  Here is an example.

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2014JG002862

Quote
Methane oxidation following submarine permafrost degradation: Measurements from a central Laptev Sea shelf borehole

Quote
Abstract
Submarine permafrost degradation has been invoked as a cause for recent observations of methane emissions from the seabed to the water column and atmosphere of the East Siberian shelf. Sediment drilled 52 m down from the sea ice in Buor Khaya Bay, central Laptev Sea revealed unfrozen sediment overlying ice‐bonded permafrost. Methane concentrations in the overlying unfrozen sediment were low (mean 20 µM) but higher in the underlying ice‐bonded submarine permafrost (mean 380 µM). In contrast, sulfate concentrations were substantially higher in the unfrozen sediment (mean 2.5 mM) than in the underlying submarine permafrost (mean 0.1 mM). Using deduced permafrost degradation rates, we calculate potential mean methane efflux from degrading permafrost of 120 mg m−2 yr−1 at this site. However, a drop of methane concentrations from 190 µM to 19 µM and a concomitant increase of methane δ13C from −63‰ to −35‰ directly above the ice‐bonded permafrost suggest that methane is effectively oxidized within the overlying unfrozen sediment before it reaches the water column. High rates of methane ebullition into the water column observed elsewhere are thus unlikely to have ice‐bonded permafrost as their source.

kassy

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Re: Arctic Methane Release
« Reply #1095 on: October 17, 2019, 07:34:57 PM »
The question was for miss or mrs Basset but i edited out the intro and a part on assuming doomerism and a part of replication but we will get to that.

But thanks for the articles.

replication
The Sverus-3 paper

Quote
Although seafloor bubble plumes were observed at two locations in the study area, our calculations suggest that regionally, turbulence‐driven diffusive flux alone accounts for the observed atmospheric CH4 enhancements, with only a local, limited role for bubble fluxes

But the russian research starts from observing plumes and then calculating the other way.
https://royalsocietypublishing.org/doi/full/10.1098/rsta.2014.0451

The fate of dissolved CH4 largely depends on the interaction between a few factors: the turnover time of dissolved CH4 in the water column, the stability of the water column against vertical mixing and the rates of turbulent diffusion and lateral advection. Dissolved CH4 in the outer ESAS requires 300–1000 days to be oxidized in the water column because CH4 oxidation rates are very low (mean±1 s.d.: 0.0988±0.1343 nM d−1, p=0.95, n=328). During this time, some of the aqueous CH4 inventory is likely to be released to the atmosphere during storms [10]. The remaining dissolved CH4, captured beneath the sea ice in winter, can spread further from the ESAS via currents (figure 4), and some can escape to the atmosphere through leads and breaks in the ice [34].


The approaches are measuring the same phenomenon in a different way.

Thornton:
Quote
However, important caveats of our limited spatial coverage must be applied to this estimate, and sea ice covers these areas for about 70% of the year [Proshutinsky et al., 1999], as discussed below. Our annual flux, not accounting for impermeable ice cover periods, is in rough agreement with previously reported regional fluxes based on measurements in open waters of the LS and ESS, 1–4.5 Tg yr−1 [Shakhova et al., 2005], though later work noted similar fluxes with additional contribution from subsea CH4 seeps [Salyuk and Semiletov, 2010]. A more recent study focused on shallower portions of the LS and ESS (6–24 m depth) and found an average flux of 287 mg m−2 d−1, based on bubble fluxes derived from sonar [Shakhova et al., 2014]. This same study also extrapolated shelf‐wide fluxes as well, reporting a flux from subsea CH4 seeps to the atmosphere of 9 Tg CH4 yr−1, and a total flux (including diffusive fluxes) of 17 Tg CH4 yr−1 for the LS and ESS, by estimating that their study accounted for 10% of extant ESAS seeps. Finally, we note that our in situ results (along with all previous in situ results) are higher than a recent model of CH4 release (bubbling + diffusion) from the Siberian continental shelves of 0.42 Tg yr−1 [Archer, 2015] but are similar to a recent modeling estimate based on Pan‐Arctic CH4 measurements from long‐term monitoring stations on land [Berchet et al., 2016].

So there is actual replication.

Second link says:
Based on a comprehensive statistical analysis of the observations and of the simulations, annual methane emissions from ESAS are estimated to range from 0.0 to 4.5TgCH4 yr−1

Doomerism
David Archer: She proposed that 50 of methane (a gigaton is 1015 grams) might erupt from the Arctic on a short time scale Shakhova (2010). Let’s call this a “Shakhova” event. There would be significant short-term climate disruption from a Shakhova event,

So now lets see what a Shakova event as proposed by Shakova looks like.
For the link http://www.realclimate.org/index.php/archives/2014/08/how-much-methane-came-out-of-that-hole-in-siberia/comment-page-3/#ITEM-17381-0

You have to get it via real climate because it does not work if you lob of the tracker ID in the link.

It is not long so just read it on the link.


Quote
Scenario 1 was realized in line with the following algorithm: the smooth methane emission growth (without account for bubble emission) should occur over the subsequent 90 years due to increase in the surface temperature by 2°С owing to the increment of carbon dioxide concentrations [3]. Such an increase should result in 5% annual growth of methane production in northern ecosystems [9] or its tenfold increase over 50 years.


Seems reasonable?

Quote
As follows from the figure, most of the shelf (80–90%) is characterized by
emission intensity ranging from 1 to 1000 μM/(m2  day).
In the remainder of the East Siberian shelf, the emission intensity is substantially higher varying from 1000 to 5400 μM/(m2  day). The recent annual methane emission is as high as 5 Tg (Tg = 1012 g). Under the emission growth in line with scenario 1, >50, >30, and approximately 15% of the East Siberian shelf should be characterized by its intensity exceeding 1000, 4000, and 20 000 μM/m2 /day, respectively. The integral annual emission should be 50 Tg of methane (for comparison, the present day methane emission from the tundra is as high as 42 Tg [3]).

So this actually just a proposal which goes from recent measures which broadly agree (4,5 or 5) which does have any really crazy assumptions temperature wise.

Sadly i cannot paste from the results so read it yourself but basically nothing in the other articles argues that this is not possible. It is not happening yet but one of the articles mentioned 70% ice cover over the year in the area and i wonder what the recent percentages are. Probably worse.

So the papers cited are actually much closer then the debate.

The possible emission translated to the temperature is 1 to 1,3 C so the whole debate is basically do you believe that ongoing global warming which will continue for a while and is amplified in the high north where there is ongoing atlantic intrusion is not going to trigger something bad.
 
And the whole bottom line is we got to do what we can to prevent that now.
We do not know where the line is (only that Archers model is wrong) and we really do not want to cross the line. You can disagree but the earth does not care and that is the worrisome bit. 
 
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oren

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Re: Arctic Methane Release
« Reply #1096 on: October 17, 2019, 08:07:02 PM »
Thank you Kassy.

gerontocrat

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Re: Arctic Methane Release
« Reply #1097 on: October 17, 2019, 08:23:32 PM »
It is not happening yet but one of the articles mentioned 70% ice cover over the year in the area and i wonder what the recent percentages are. Probably worse.
Ask and it shall be given.

Open water graphs for the ESS & Laptev attached. SST's also very high - warmth reaching the ocean floor in the large area < 50 m and even <10 m below the surface ?

It hasn't happened yet but the ESS & Laptev are steadily losing more ice for longer in the year (see area graphs as well).
« Last Edit: October 17, 2019, 08:28:51 PM by gerontocrat »
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Re: Arctic Methane Release
« Reply #1098 on: October 27, 2019, 02:16:07 AM »
Apologies for the duplicate post, I'm reposting this here (from the stupid questions thread) as I think it's a more appropriate thread.

I'm looking for recent methane concentration data from the Tiksi weather station, but the most recent data I can find on the NOAA website is over a year old.

Is the station still operational? Is NOAA still collecting this data? Or am I just being impatient?

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Re: Arctic Methane Release
« Reply #1099 on: October 31, 2019, 11:39:39 PM »
A tiny ESAS/Semiletov update.

First pictures and video of the largest methane fountain so far discovered in the Arctic Ocean.

https://siberiantimes.com/other/others/news/first-pictures-and-video-of-the-largest-methane-fountain-so-far-discovered-in-the-arctic-ocean/

Quote
Unexpectedly high speed of degradation of subsea permafrost has been recorded.

'In some areas the roof of subsea permafrost thawed to the stability horizons of gas hydrates. Moreover, it has been proved that over the past 30 years speed of vertical degradation of subsea permafrost doubled compared to previous centuries and reached 18 centimetres per year which is significantly higher than in earlier estimates', said professor Semiletov.

'This result makes us reconsider the belief that subsea permafrost is stable and can only thaw by a few metres by the end of 21st century', he stressed.