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TerryM

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Re: Arctic Methane Release
« Reply #450 on: October 21, 2017, 09:57:03 AM »
A-Team
That was a tome.
I need more time.
Terry

oren

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Re: Arctic Methane Release
« Reply #451 on: October 21, 2017, 10:39:34 AM »
Thanks A-Team.

gerontocrat

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Re: Arctic Methane Release
« Reply #452 on: October 21, 2017, 04:29:12 PM »
A-Team
That was a tome.
I need more time.
Terry
Maybe time is the one thing we have not got?
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

TerryM

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Re: Arctic Methane Release
« Reply #453 on: October 21, 2017, 07:48:50 PM »

A-Team

Would English's studies of tree stumps ice ferried from Siberia to behind the Ellesmere ice shelf help at all with their Holocene timing and temperatures? IIRC he was able to date the most recent time that the ice shelf had not been in place with some accuracy. Ice flow rafting the logs across the Arctic ocean at that time might give some indication of ESAS temperatures near the Thermal Optimum.


Or not.
Terry

AbruptSLR

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Re: Arctic Methane Release
« Reply #454 on: October 21, 2017, 09:51:35 PM »
A-Team
That was a tome.
I need more time.
Terry
Maybe time is the one thing we have not got?

Hopefully, readers appreciate that multiple positive feedback mechanisms contribute to the currently accelerating Arctic Amplification, and that Arctic Amplification will interact synergistically with Arctic methane releases as the decades go by.  This can result in a dynamical climate attractor that could progressively ratchet the effective ECS into the 5C range by 2100.
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A-Team

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Re: Arctic Methane Release
« Reply #455 on: October 22, 2017, 12:43:28 PM »
I worked through all 530 AGU abstracts mentioning methane and found two more of interest. The underwater geology of Arctic Ocean continental shelf has a rich and complicated history mostly unfamiliar to mid-latitude climate scientists, leading to poorly-grounded objections to ESAS methane release that have to be tediously explained over and over.

The four N Shakhova papers from 2017 are all open access. The abstracts really don't capture what the best of what's in the articles; often the internal discussion provides much better background and explanations of the significance. Comments and questions of peer-reviewers are also available and instructive.

The April 2017 interview with Shakhova briefly summarizes responses to many asinine objections raised up over the years by CO2-oriented scientists who perceive methane as mainly a threat to the primacy of their preferred narrative. It's probably worth pulling together more detailed responses from these recent articles as well as excellent material scattered up-forum.

https://www.the-cryosphere.net/11/1333/2017/tc-11-1333-2017.pdf open access
https://www.biogeosciences.net/14/2283/2017/bg-14-2283-2017.pdf open access
https://www.nature.com/articles/ncomms15872 open access
https://www.the-cryosphere.net/11/2305/2017/tc-11-2305-2017.pdf open
http://envisionation.co.uk/index.php/nick-breeze/203-subsea-permafrost-on-east-siberian-arctic-shelf-now-in-accelerated-decline

OS43B-02: Relict thermokarst carbon source kept stable within gas hydrate stability zone of the South Kara Sea
A Portnov et al

Substantial shallow sources of carbon can exist in the South Kara Sea shelf, extending offshore from the permafrost areas of Yamal Peninsula and the Polar Ural coast. Our study presents new evidence for >250 buried relict thermokarst units. These amalgamated thawing wedges formed in the uppermost permafrost of the past and are still recognizable in today’s non-permafrost areas. Part of these potential carbon reservoirs are kept stable within the South Kara Sea gas hydrate stability zone (GHSZ).

We utilize an extensive 2D high-resolution seismic dataset, collected in the South Kara Sea in 2005-2006 by Marine Arctic Geological Expedition (MAGE), to map distinctive U-shaped units that are acoustically transparent. These units appear all over the study area in water depths 50-250 m. Created by thermal erosion into Cretaceous-Paleogene bedrock, they are buried under the younger glacio-marine deposits and reach hundreds of meters wide and up to 100 meters thick.

They show the characteristics of relict thermokarst, generated during ancient episodes of sea level regression of the South Kara Sea. These thermokarst units are generally limited by the Upper Regional Unconformity, which is an erosional horizon created by several glaciation events during the Pleistocene.

On land, permafrost is known to sequester large volumes of carbon, half of which is concentrated within thermokarst structures. Based on modern thermokarst analogues we demonstrate with our study that a significant amount of organic carbon can be stored under the Kara Sea.

To assess the stability of these shallow carbon reservoirs we carried out GHSZ modeling, constrained by geochemical analyses, temperature measurements and precise bathymetry. This revealed a significant potential for a GHSZ in water depths >225 m. The relict thermokarst carbon storage system is stable under today’s extremely low bottom water temperatures ~ -1.7 °C that allows for buried GHSZ, located tens of meters below the seabed.

Noteworthy, vast parts of GHSZ do not expose on the seafloor, since both upper and lower GHSZ boundaries occur clearly sub-seafloor. Our findings show that under the deepest regions of the South Kara Sea, large areas of relict thermokarst may presently exist within the GHSZ of unique configuration, and therefore provide substantial methane source for gas hydrate.


B21C-1973: Methane fluxes from intense bubbling seep sites: Mapping and Quantification from the seafloor up to the atmosphere
J Greinert

Despite the ever increasing number of seep sites being discovered in shelf and continental slope areas, sites where dissolved or free gas fluxes at the seafloor fuel a significant sea surface gas flux into the atmosphere are rare. Here, we report on multi-year studies from a very active seep site in the Dutch North Sea that has been revisited several times since 2009, with large-scale surveys including multi-beam based bubble mapping, CTD water column sampling, direct ROV observations, sub-seafloor free gas mapping and CRDS-based sea surface flux and atmospheric measurements.

More than 800 individual flares in five main clusters were recorded and first approximations yield 280L of CH4 per minute being released from the seafloor in the entire area. These fluxes created sea surface anomalies even in the strongly stratified water column during the summer period.

Atmospheric concentrations increased by almost 1ppm above the strongest flare cluster in 42m water depth. Currently ongoing studies that aim at merging single-beam and multi-beam echosounder data on a meter scale will verify if the previously calculated seafloor gas flux estimates are correct, or if even higher fluxes occurred that explain the significant increase in the atmosphere. Spatial bubble dissolution modeling will be applied to calculate if the newly determined fluxes can support the measured sea surface concentrations and if ocean-atmosphere equilibration supports the observed atmospheric increase.

In any case, the clear spatial correlation between seafloor gas release, sea surface and atmospheric anomalies prove that the methane emanating from the seafloor is the source of the increased atmospheric CH4 concentration. Optical studies show that massive and constant gas release is needed to have such an effect. This study can be used as an ideal case study for comparison to other high intensity seeps and their potential for having local effects on CH4 budgets.
« Last Edit: October 22, 2017, 01:34:27 PM by A-Team »

A-Team

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Re: Arctic Methane Release
« Reply #456 on: October 22, 2017, 01:33:59 PM »
Here's a start on listing the endless objections to ESAS methane, mostly taken from the 2017 Shakhova interview. It all bears an uncanny resemblance to a dysfunctional corporate leadership game called "bring me another rock".

The permafrost seal didn't have time to melt
The permafrost seal is melting but the time scale is millennia away
The permafrost seal melted during the Eemian and earlier inter-glacials
The taliks all froze after Holocene inundation
There are no mechanisms that could damage the permafrost layer
The migration routes for the methane are fairly minor so the volume is insignificant
The minor migration routes aren't degrading further into hotspots
The hotspots will soon deplete their underground reservoirs
The geological faults do not bypass the permafrost seal
The ice scours do superficial damage to subsurface permafrost
There's no methane down there
There's no methane left down there
The release of methane can't be proven to be accelerating
There wasn't any methane released during the Eemian
The previously accumulated methane was all released during the Eemian
There wasn't any build-up of methane during the Pleistocene
There's no massive groundwater incursion of freshwater
There's no coastal permafrost erosion of any significance in Siberia
Thermokarst only develops on land
The six rivers sediment does not lead to biogenic methane
The Holocene has been going on too long and peaked at 5 kyr
The shelf was all flooded at 11 kyr
There won't be wind disruption of ocean stratification until the ice is gone in 2050
The sunshine doesn't penetrate 10 m of clear water to warm the upper shelf
There are important lessons for shallow shelf from deep oceanic clathrate
The armchair models don't need observational calibration
There aren't any inter-glacial methane pulses found in Greenland ice cores
The methane gets consumed in bottom sediments
The bubbles lose their methane before reaching the surface
The bubbles dissolve in the water and are quickly consumed
The consumption of methane by bacteria leads to offsetting algal blooms
The methane doesn't reach the atmosphere
The methane reaching the atmosphere is quickly broken down
The half-life is too short for methane to have any effect
The only time scales that matter are 2100 and multi-millennial
The equivalence multiplier we should use for methane is 20
There'll always be enough hydroxyl radical
« Last Edit: October 22, 2017, 04:24:46 PM by A-Team »

TerryM

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Re: Arctic Methane Release
« Reply #457 on: October 22, 2017, 06:39:53 PM »
A-Team
Just want to clarify that my "tome" post was not a criticism. Some subjects require more extensive documentation to get us up to speed.


I've wondered if the pockmarked floor of Hudson Bay might hold answers for what the ESAS might look like in the not too distant future? Some portion of the pingo like structures are quite recent, but I don't know if there is evidence of a large number of them erupting almost simultaneously.
Hudson Bay might serve as an example of a basin that had been ice covered during most recent glaciation, but still held a large number of methane pockets that erupted when the ice sheet withdrew, and when the floating ice cleared seasonally.


AFAIK no gigantic plumes there because there was no massive methane buildup under frozen permafrost, but the pingo like structures do indicate a collapse of clathrate structures.


Terry


BTW
I'd like to know more about Foxe Basin with it's "dirty" ice.


miki

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Re: Arctic Methane Release
« Reply #458 on: October 22, 2017, 10:11:24 PM »
In the meanwhile, on land ... a little away from the Arctic, but I'll post it here :-)

http://pubs.acs.org/doi/full/10.1021/acs.est.7b03525

Comparisons of Airborne Measurements and Inventory Estimates of Methane Emissions in the Alberta Upstream Oil and Gas Sector.

Matthew R. Johnson, David R. Tyner, Stephen Conley, Stefan Schwietzke, and Daniel Zavala-Araiza


'This is a really big deal': Canada natural gas emissions far worse than feared
Pioneering peer reviewed study measured methane emissions from oil and gas infrastructure in two regions in Alberta: ‘If we thought it was bad, it’s worse’
https://www.theguardian.com/world/2017/oct/17/study-methane-emissions-from-alberta-oil-and-gas-wells-are-worse-than-thought#img-1

A-Team

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Re: Arctic Methane Release
« Reply #459 on: October 23, 2017, 05:25:17 PM »
Quote
Terry: Methane requires extensive explanations ... wondered if the pockmarked floor of Hudson Bay methane pockets that erupted when the ice sheet withdrew and when  ice cleared  seasonally.
I'm looking forward to reviewing the whole ESAS methane business, where it stands as of 2017, one line at a time, starting from the beginning. The freeze season forum is getting trolled pretty bad; fall visitation is down 90%, not worth the effort.

Reading that last Shakhova interview is really harrowing, especially since she's been hearing the objections and misunderstandings for years but sees no reasoning there that to alter outcome expectations. People here can't conceptualize the vast Siberian permafrost lands nor how scientifically familiar the Russians are with them after some centuries. The ESAS alone is 3x the size of Texas or France.

The poster child for post-glacial methane rebound is more Barents Sea. I don't know if Hudson Bay has had the organic-rich sediment inflows that are needed for biotic methane, nor the erosion of the permafrost periphery, nor if the Canadian shield there holds much natural gas.

Sediments in the ESAS can be 20 km thick. Shakhova has shifted from thermal over to biotic methane after the isotope study. Says stable clathrates have been found by South Koreans despite shallow water but are an incidental component, all that matters is total capped reservoir (truly vast) and escape rates (not linear in time, instead accelerating).

http://science.sciencemag.org/content/356/6341/948 (plus googScholar 'Alun Hubbard methane')

AbruptSLR

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Re: Arctic Methane Release
« Reply #460 on: October 23, 2017, 05:45:38 PM »
While this thread is about potential Arctic methane releases, Andreassen et al (2017, DOI: 10.1126/science.aal4500) concludes as follows:

Extract: "We propose that these processes were likely widespread across past glaciated petroleum provinces and that they also provide an analog for the potential future destabilization of subglacial gas hydrate reservoirs beneath contemporary ice sheets."

We should not forget that the only contemporary ice sheet comparable to the paleo marine ice sheet in the Barents Sea basis, that is at risk of being destabilized this century is the WAIS; which could make a significant contribution to methane emissions into the atmosphere give a sufficient abrupt collapse scenario.
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A-Team

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Re: Arctic Methane Release
« Reply #461 on: October 23, 2017, 09:34:11 PM »
Quote
WAIS could make a significant contribution to methane emissions into the atmosphere give a sufficient abrupt collapse scenario.
I for one have relied on your most excellent coverage and assessment of this contingency over the years. I should have mentioned above that Barents methane release may have mostly happened already, that Greenland methane is improbable any time soon, that Laptev methane release is ongoing too, that the Beaufort shelf is too small to concern us (though interesting things have gone on there), and that the ESAS permafrost is degrading rapidly and perhaps transitioning shortly from near-term threat to outright existential problem.

The rate of degradation of the sub-sea permafrost is somewhat lost in the overly complex Fig.2 and its widely scattered caption in the NatComm Shakhova paper. Where they re-drilled previous boreholes, the ice-bonded permafrost table (IBPT) had dropped 4.5 meters, much much farther than hypothesized in next millennium models.

https://www.nature.com/articles/ncomms15872 open access

Quote
The IBPT positions observed in 1982–1983 at sites 301, 303, 304 and 305 were at 3.3–4.2 m, 5.8–7 m, 8.3–8.6 m and 16–16.8 m b.s.l., correspondingly (Table 1). In 2012–2013, the IBPT positions were identified at 8.6 m, 11.4 m, 12.8 m, and 19.3 m b.s.l. at sites 4D-14 (former 301), 4D-13 (former 303), 3D-14 (former 304), and 2D-13 (former 305), correspondingly. IBPT deepening during the last 31–32 years varied from 9.3 to 18.3 cm year−1 with a mean rate of 14±3.1 cm (mean±s.e.m.) per year during the last 31–32 years.
« Last Edit: October 23, 2017, 10:08:17 PM by A-Team »

Shared Humanity

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Re: Arctic Methane Release
« Reply #462 on: October 23, 2017, 09:56:44 PM »
The freeze season forum is getting trolled pretty bad; fall visitation is down 90%, not worth the effort.

http://science.sciencemag.org/content/356/6341/948 (plus googScholar 'Alun Hubbard methane')

Happens every freeze season as traffic falls. Trolls can post without getting refuted as thoroughly as would happen in the melt season. They often arrive in pairs so as to appear to be engaged in a thoughtful probing discussion.

A-Team

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Re: Arctic Methane Release
« Reply #463 on: October 23, 2017, 11:10:14 PM »
Quote
Trolls can post without getting refuted as in the melt season. They often arrive in pairs
Or threesomes, adopting various levels of obviousness, some holing up in sleeper cell posts until the signal is given. They've been gotten wrist-slaps in the past for 2020 divinations but these same disruptors have been tolerated for years and years. Garbage is better intercepted en route before the forums are defaced.

In terms of Arctic methane, the situation is even worse: S&S get non-stop harassment, the trolls being influential scientists from the CO2 community rather than the ignoramuses we get here.

Look at the ASI blog, it's totally out of control, I never go there any more. The disrupters have moved on now to the forums, probing them to see if anyone is moderating. The agenda this week is to build a fake consensus that it's all a long long ways off, check back in five years time if then.

What becomes of the average joe trying to follow the issue and maybe get to the next level of understanding? It's not a climate change resource for them any more, too confusing.

The 'Recent Post' section most days, just angry people venting about politics. Hmmm, maybe someone could start a forum called Angry People Venting About Politics and all the conspiracies could be consolidated there. Some of these people had been really strong contributors.

Over time I've watched the better posters, one after the other, leave the site permanently to go off on their own, just to get a moderated environment. Which just scatters the effort thinner than ever. But I'm thinking about doing that too; I'm tired of these same trolls chasing me around from one forum to another. Too bad, there's a LOT of good people here.

Is Neven really not coming back until next May?
« Last Edit: October 24, 2017, 10:07:48 AM by A-Team »

TerryM

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Re: Arctic Methane Release
« Reply #464 on: October 24, 2017, 01:41:55 AM »
A-Team


Prior to having taken some years off I'd followed S&S closely. I think I'll try to get up to date by reading the 6 Shakhova 2017 interviews papers you've listed above.
I doubt there's much biotic methane in the Canadian Shield. The Hudson Bay Lowlands however may be a very different story.
A guide once showed me his personal collection of fossils from the eastern James Bay/Hudson Bay region. Many indicated a shallow warm sea, and fossils that somehow didn't get crushed, ground up, or pushed south.
Was the " All that matters is the capped reservoir and escaped routes" yours or Shakhova's.


FWIW I've tried to steer politics to the "rest" section, not always successfully. Angry old men with keyboards can be a nasty thing to stumble across. An apology to all.


Terry
« Last Edit: October 25, 2017, 01:58:20 AM by TerryM »

A-Team

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Re: Arctic Methane Release
« Reply #465 on: October 24, 2017, 11:44:17 AM »
Terry, I'm doing the same, revisiting the whole matter now that they've got more of their voluminous field data out into papers. So far, Cid_Yama's analysis up-forum has been spot-on.

Those words are my encapsulation of what Shakhova says in the N Breeze interview. Given a non-native speaker of English, with verbosely articulated concepts and awkwardly written scientific prose -- yet doing very important research in a very remote area -- I felt a short and pithy summary was worthwhile. The raw transcript or youtube can be consulted when there's any question what was actually said. 

People have wondered aloud why the most recent paper sat in peer review at NatComm for 11 months. Actually it is a minor miracle something still so jumbled ever got published, ie how awful was the paper when first submitted? And what took so long for 2014 field work to get written up? Actually long delays are not at all unusual and so-so communications skills are very common among scientists. Just read the AGU17 abstracts.

Here are the relevant sections. I read them as saying the methane hydrate objection is a double red herring. Clathrates are in fact present, contrary to trolling from the CO2 side, but irrelevant to the discussion, contrary to follow-on trolling. Bring me another rock.

With or without hydrates, there's an undisputed huge volume of over-pressurized methane gas under the permafrost seal that will bubble up the first narrow escape route that opens up and blowout with further seal failure. With a million disintegrating corks in a million bottles of champagne, what could possibly go wrong. The well blowouts clip from the paper makes the case for pressure containment (bottom).

I find this very troubling, that this GHSZ stability zone keeps getting brought up when it's both wrong and irrelevant. Especially by scientists who know better. It raises all sorts of red flags for me about motivations. Research should be discussed strictly on its merits.

Quote
Dr. Shakhova: We use an analogy where we compare the East Siberian Arctic Shelf to a bottle of champagne. So the gas produces within this bottle and it keeps accumulating as long as the cork serves as an impermeable lid.

This lid is subsea permafrost. Before it was just permafrost [on land] but after it was submerged it became subsea permafrost and served to preserve an increasing amount of gas produced from its release to the ocean and atmosphere above. While this lid is impermeable, there is nothing to worry about.

But when this lid loses its integrity, this is when we start worrying. This is where the methane is releasing and the amounts of methane currently releasing makes us think it will increase as a result of the disintegration of this permafrost body.

Nick Breeze: In relation to the ESAS, how do you know these hydrates are there and that they are a potential threat?

Dr. Shakhova: The importance of hydrates involvement in methane emissions is overestimated. The hydrate is just one form of possible reservoirs, in which pre-formed methane could be preserved in the seabed if there are proper pressure/temperature conditions; it is just the layer of hydrates composes just few hundred of meters – this is a very small fraction compared to thousands of meters of underlying gas-charged sediments in the ESAS.

Dr. Semiletov added that the 5 billion tonnes of methane that is currently in the Earth’s atmosphere represents about one percent of the frozen methane hydrate store in the East Siberian Arctic Shelf. He finishes emphasising  “…but we believe the hydrate pool is only a tiny fraction of the total.”

Dr. Shakhova: The second point is that the hydrates are not all of the gaseous pool that is preserved in this huge reservoir. This huge area is 2 million square kilometres. The depth of this sedimentary drape is a few kilometres, up to 20 kilometres at places. Generally speaking, it makes no difference if gas releases from decaying hydrates or from other free-gas deposits, because in the latter, gas also has accumulated for a long time without changing the volume of the reservoir; for that reason, gas became over pressurised too.

Unlike hydrates, this gas is preserved free; it is a pre-formed gas, ready to go. Over pressured, accumulated, looking for the pathway to go upwards.

The point Shakhova and Semiletov are making is that the question of whether there are methane hydrates present beneath the permafrost is really not important. The estimated amount of hydrates, 1500 billion tonnes, is actually only a tiny proportion of the actual pressurised methane store beneath the gas hydrate stability zone.

Dr. Shakhova: The third point is that the hydrates, despite disbelief from some scientists, have already been found in the ESAS. We know from personal communication that the South Korean expedition was accomplished in 2016 and they sampled the hydrates. I believe, this data will be published soon. However, hydrates could only be sampled if they remain stable. After hydrates are destabilised, we can only sample gas releasing from these decaying deposits.

In our observations, we have accumulated the evidence that this gas front is propagating in the sediments. To me as a scientist, these points are enough to be convinced that methane release in the ESAS is related to disintegrationof subsea permafrost and associated destabilisation of seabed deposits whether it is hydrates or free gas accumulations.

The NatComm paper describes a drilling gas blowout that fountained up 10 meters over sea level:

Quote
Numerous gas blowouts followed by long-lasting gas flow have been reported from permafrost areas disturbed by exploratory drilling in Siberia, both on-land and offshore. Such gas blowouts were reported from shallow permafrost-related gas-hydrate accumulations at depths of only a few tens of metres, starting from 20 m depth.

Offshore, a particularly powerful gas discharge erupting from a well drilled through the subsea permafrost was documented in the Pechora Sea shelf; a gas–water fountain originating from 50 m beneath the sediment surface in 64 m-deep water reached 10 m above the ship. Echo sounding carried out at the drilling site 10 days after this event revealed an underwater fountain ∼10 m in diameter, with a height ∼40 m above the sea floor (ref 56)
« Last Edit: October 24, 2017, 12:22:54 PM by A-Team »

gerontocrat

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Re: Arctic Methane Release
« Reply #466 on: October 24, 2017, 01:50:53 PM »
This is a quote from the oil and gas issues thread.

"Rosneft also plans to resume drilling in the Barents Sea next year and in the Kara Sea within two years, thus committing itself to conduct drilling works across the entire Russian section of the Arctic."

Methinks Rosneft is going to put a lot of holes into that impermeable sub-sea permafrost. But what could possible go wrong?

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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ivica

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Re: Arctic Methane Release
« Reply #467 on: October 24, 2017, 03:07:16 PM »
your "joe" reminds me on kids of articio. (can't find relevant post/thread - portfolio seems deleted. please, ignore it)
« Last Edit: October 24, 2017, 09:47:57 PM by ivica »

salbers

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Re: Arctic Methane Release
« Reply #468 on: October 29, 2017, 09:09:21 PM »
This will be the year to go.  Wonder why it's in NO, it's always been in SF.
Interesting to see all the updates about AGU and S&S. The AGU Fall Meeting is in New Orleans this year and next due to subway construction in S.F.

AbruptSLR

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Re: Arctic Methane Release
« Reply #469 on: November 04, 2017, 12:29:37 AM »
Paul Beckwith provides a convenient video summary associated with the recent Sharkhova & Semiletov et al paper, entitled "Thawing Open Pandora's Methane Box":



Extract: "Vast amounts of methane exists within ocean floor sediments on the Eastern Siberian Arctic Shelf, in the form of methane hydrates & free methane gas. Up to recently, gas release to the shallow water column (50 meters deep) & atmosphere has been slow, with the subsea permafrost acting as a million corks on a million champagne bottles to contain the methane. Now, rapid thawing of the permafrost has released 10% of the corks, allowing rapid ongoing increases in methane release."
« Last Edit: November 04, 2017, 03:34:57 PM by AbruptSLR »
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gerontocrat

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Re: Arctic Methane Release
« Reply #470 on: November 04, 2017, 10:35:56 AM »
Anybody got any idea how long it is until the rest of the corks pop?
"Para a Causa do Povo a Luta Continua!"
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solartim27

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Re: Arctic Methane Release
« Reply #471 on: November 04, 2017, 03:31:21 PM »
Anybody got any idea how long it is until the rest of the corks pop?
28 days... 6 hours... 42 minutes... 12 seconds. That... is when the world... will end.
FNORD

AbruptSLR

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Re: Arctic Methane Release
« Reply #472 on: November 04, 2017, 04:12:45 PM »
Anybody got any idea how long it is until the rest of the corks pop?
28 days... 6 hours... 42 minutes... 12 seconds. That... is when the world... will end.

gerontocrat,

I very much appreciate solartim27's response, in that the topic of abrupt release of methane from the ESAS is fertile ground for non-scientific speculation, while true scientific analysis requires models that are too complex for the current state of the art.

For example during super interglacial periods climate sensitivity and Arctic Amplification have been much higher than what is reflected in climate models for current conditions, but it is difficult to say how much of this higher climate sensitivity and higher Arctic Amplification came from progressive releases of methane from the ESAS.

Per the first image the ESAS contains about as much methane in hydrate form as from all the rest of the sources in the world combined, and the full release of all of this methane would take tens of thousands of years if we progress to super interglacial conditions and then stay there.

But until 2100, I would say that in addition to the shallow water releases that Paul Beckwith's video address, I list the follow three other possible feedback mechanisms that could contribute to the release of substantial amounts of methane from the ESAS before 2100:

1. The second image shows that some climate models (with BAU forcing) project that beginning around 2035 the AMOC could start reaching further into the Arctic Ocean Basin thus conveying significant new sources of heat to the seafloor (which would then take some decades to penetrate to the hydrate zone).
2. Advance climate models have shown that if the West Antarctic Ice Sheet were to abruptly collapse this century, that this would push a lot of warm water from the Pacific Ocean thru the Bering Strait into the Arctic Ocean Basin, where again it would take some decades for the heat to migrate from the seafloor to the hydrate zone.
3.  The last image shows that under the classical Clathrate Gun Hypothesis most of the methane is release from the edge of the continental shelf/slope due to submarine landslides; which would occur much soon than the majority of the ESAS hydrate zones.

If you are old, none of these sources are likely to be a problem in your lifetime; however, if you are concerned about the young then I would be concerned.

Best,
ASLR
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

mitch

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Re: Arctic Methane Release
« Reply #473 on: November 04, 2017, 04:20:25 PM »
The most important event to warm the Arctic shelves is not the present global warming but the flooding of the shelves, which ended at roughly 6000 BP. Average temperature then changed from roughly -15C to -1C. That temperature change must diffuse downward through the sediments to warm either the permafrost or the hydrate layer.   

If we wanted to see the current warming, we need to take temperature measurements in the upper 10 m of the sea floor. Once we do that, we can evaluate how fast heat is diffusing down. However, most of the response right now is caused by early Holocene shelf flooding.

Shared Humanity

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Re: Arctic Methane Release
« Reply #474 on: November 04, 2017, 04:24:01 PM »
Am I the only one here who struggles to listen to Beckwith? There is something about his voice that causes me to grind my molars.

AbruptSLR

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Re: Arctic Methane Release
« Reply #475 on: November 04, 2017, 04:43:32 PM »
However, most of the response right now is caused by early Holocene shelf flooding.

mitch,

The point that you make is correct; however, what one's beyond the state of the art climate model does with this information is just as critical (as all climate model projections assume the introduction of warming that you note).  First, one needs to get the hydrates in the correct zone to match the observed and historical record, then one needs to correct the overburden depth to account for the history of wave and current erosion and sediment deposition. 

The linked reference points out that per their 1D models the Arctic continental shelf methane hydrate stability zone (HSZ) can take ~ 10 to 20 kyrs to respond to changes in initial temperature conditions associated with the end of the last ice age.  However, while it is pleasant to think of middle of the 10 to 20 kya range, as the first attached image indicates the Holocene began about 11 kya and thus we should now start to see portions (especially in the shallow water zones with well mixes waters and along the edge of the continental shelf with 2D warming) of the HSZ becoming unstable due to the global temperature increase leading to the beginning of the Holocene:

Valentina V. Malakhova & Alexey V. Eliseev (2017), "The role of heat transfer time scale in the evolution of the subsea permafrost and associated methane hydrates stability zone during glacial cycles", Global and Planetary Change, https://doi.org/10.1016/j.gloplacha.2017.08.007

http://www.sciencedirect.com/science/article/pii/S0921818117301273

Abstract: "Climate warming may lead to degradation of the subsea permafrost developed during Pleistocene glaciations and release methane from the hydrates, which are stored in this permafrost. It is important to quantify time scales at which this release is plausible. While, in principle, such time scale might be inferred from paleoarchives, this is hampered by considerable uncertainty associated with paleodata. In the present paper, to reduce such uncertainty, one–dimensional simulations with a model for thermal state of subsea sediments forced by the data obtained from the ice core reconstructions are performed. It is shown that heat propagates in the sediments with a time scale of ∼ 10-20 kyr. This time scale is longer than the present interglacial and is determined by the time needed for heat penetration in the unfrozen part of thick sediments. We highlight also that timings of shelf exposure during oceanic regressions and flooding during transgressions are important for simulating thermal state of the sediments and methane hydrates stability zone (HSZ). These timings should be resolved with respect to the contemporary shelf depth (SD). During glacial cycles, the temperature at the top of the sediments is a major driver for moving the HSZ vertical boundaries irrespective of SD. In turn, pressure due to oceanic water is additionally important for SD ≥ 50 m. Thus, oceanic transgressions and regressions do not instantly determine onset s of HSZ and/or its disappearance. Finally, impact of initial conditions in the subsea sediments is lost after ∼ 100 kyr. Our results are moderately sensitive to intensity of geothermal heat flux."

Furthermore, one would not expect past recent interglacial to have removed most of the paleo methane hydrates as:
1. Over the past million years only two interglacial periods (MIS 11 & 5) have a reasonable combination of ocean temperature and sea level to both inundate and then begin to degrade the submerged permafrost in the ESAS (see the blue curve in the second attached image).
 2. However, during both the MIS 11-Holsteinian, and the MIS 5-Eemian, eras the duration of conditions equal or above modern conditions was less than 5,000 years which is short compared to the Holocene where modern condition have existed for almost 12,000 years (see the third attached image).
3. 5,000 years is too short of a period for the heat of the seawater inundating the ESAS to adequately degrade the submerged permafrost to release significant quantities of methane, while the 12,000 years of warming, during the Holocene, is very near to the duration necessary conditions to begin to release the least stable of the submerged methane regions.
4.  The rapid loss of Arctic sea ice extent has exposed the portions of the ESAS in less than 50m of water depth to storm wave mixing that has conveyed relatively warm sea water to the shallow regions of the ESAS which in certain susceptible regions (such as regions with high erosion of sediment overburden above the methane bearing layers, say due to currents and wave action during inundation 12,000 years ago) to cross their thresholds for releasing methane (as observed by S&S in localized areas).

Best,
ASLR
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wili

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Re: Arctic Methane Release
« Reply #476 on: November 04, 2017, 08:12:25 PM »
"Am I the only one here who struggles to listen to Beckwith? There is something about his voice that causes me to grind my molars."

That, and his science is sometimes...sketchy/speculative...
"A force de chercher de bonnes raisons, on en trouve; on les dit; et après on y tient, non pas tant parce qu'elles sont bonnes que pour ne pas se démentir." Choderlos de Laclos "You struggle to come up with some valid reasons, then cling to them, not because they're good, but just to not back down."

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Re: Arctic Methane Release
« Reply #477 on: November 04, 2017, 08:46:37 PM »
"Am I the only one here who struggles to listen to Beckwith? There is something about his voice that causes me to grind my molars."

That, and his science is sometimes...sketchy/speculative...
He is on our side, but....
I've been hoping for years that he would go back and complete his PHD, it might serve to mellow his rather abrasive tone.
Terry

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Re: Arctic Methane Release
« Reply #478 on: November 05, 2017, 08:09:43 AM »
An interesting discussion about methane release.

My question is, for those who down play the importance of methane release, how do they explain pingo explosions?

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Re: Arctic Methane Release
« Reply #479 on: November 06, 2017, 04:03:07 PM »
I strongly recommend reading and re-reading the April 2017 Shakhova & Semiletov interview and going through the nine pictures in the NatComm paper until you get it. A lot of people posting here simply do not grasp the basic 1,2,3 of what's been observed nor the whats and whys S&S are proposing.

After assimilating the nine pictures, perhaps then opinionate on whether it is right or wrong or too soon to say. More work is needed, it always is; however the nine pictures in the NatComm paper show where it's headed: additional bubble and drill core-calibrated, repeat sonar surveys.

Essentially all observational data on the East Siberian shelf methane derives from field work by S&S and colleagues. Do you understand what that means? It means people pontificating on ESAS methane need to base off S&S data. Very few do. It means models have to be calibrated with S&S data. Very few are.

The vast majority of ESAS secondary coverage falls into psychological categories such as projection, competition, ignorance, misunderstanding, denial, and panic. Very little commentary is data-driven.

Cubicle-based, lower-latitude authorities seem to think the ESAS consists of a vast submerged tundra, with featureless even layers of permafrost and clathrates at depth warmed from below by a uniform geothermal gradient, extending out to the edge of the continental shelf under a unchanging near-frozen placid sea.

Inconveniently, the East Siberian shelf and its sedimentary drape are very heterogenous structurally because of a long complicated history of interaction with adjacent permafrost land, enormous sediment-laden rivers and paleo-rivers, ocean waters that advance and retreat with glacial cycles, with land exposed to very cold air at low stands, complicated by a 53m sill at the Bering Strait and a 1 km thick ice shelf at the last glacial maximum and thermokarst processes that still proceed even when permafrost is submerged.

Because submerged permafrost does not form a homogeneous lid, degradation of lid quality begins long before it thaws uniformly to its full thickness. Multiple escape routes have already developed in inhomogeneous regions such thawed or never-frozen taliks, thermokarst, glacial scours, pockmarks, convective salt fingering, groundwater intrusion, and geological faults. Not only that, the limited number of revisited escape routes are getting worse, fast. For the large volume of over-pressurized free methane gas that is already sitting there.

S&S are primarily concerned with this heterogeneity and its consequences. That's a good start in those nine pictures in the NatComm paper. There's more though: the special journal issue on the Oden's research and the 2018 papers now visible as AGU17 abstracts:

https://www.nature.com/articles/ncomms15872
https://www.the-cryosphere.net/special_issue652.html special issue of The Cryosphere
https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/271328 Semiletov
https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/214305 Semiletov
https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/216749 Semiletov
https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/228715 Weidner
https://agu.confex.com/agu/fm17/meetingapp.cgi/Paper/214305 Jakobsson
« Last Edit: November 06, 2017, 04:32:09 PM by A-Team »

Shared Humanity

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Re: Arctic Methane Release
« Reply #480 on: November 06, 2017, 04:13:11 PM »
I have read the entire interview and I have no doubt the ESAS represents a real danger and my biggest concern is that it is irreversible. What do we do if this is the case?

AbruptSLR

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Re: Arctic Methane Release
« Reply #481 on: November 06, 2017, 04:56:29 PM »
I have read the entire interview and I have no doubt the ESAS represents a real danger and my biggest concern is that it is irreversible. What do we do if this is the case?

Shared Humanity,

As to what to do if this is the case, I believe that the most important step is to get 'consensus science' (including AR6 & CMIP6) to acknowledge, and to model, the ESAS as accurately as they can, including by calibrating their models to past super interglacial periods that exhibited high Arctic Amplification (see Wolfe et al 2017 and the first attached image).  Furthermore, 'consensus science' should more clearly state their assumptions and limitations of their projections, for example:

1. S&S only consider shallow water conditions (see the second image) and one dimensional heat flow (see the third attached image).  However, heat flow at the edge of the continental shelf leading to the slope presents a two dimensional heat flow situation (that has been transmitting 2D heat flux since the beginning of the Holocene) that may well become significant w.r.t. the Clathrate Gun Hypothesis in a few short decades time, as submarine landsides can release large volumes of methane buddle that can find their way to the atmosphere.

2. Current 'consensus science' radiative forcing scenarios (like the RCP scenarios) all ignore Hansen's ice-climate feedback mechanism that would drive large amounts of warm seawater into the Arctic Basin, particularly along the edge of the ESAS continental shelf.

Until decision makers are publically presented with 'consensus science' that honestly present such risks, they will not take appropriate action to deal with our situation.

For ease of reference see:

Alexander P. Wolfe, Alberto V. Reyes, Dana L. Royer, David R. Greenwood, Gabriela Doria, Mary H. Gagen, Peter A. Siver and John A. Westgate (May 2017), "Middle Eocene CO2 and climate reconstructed from the sediment fill of a subarctic kimberlite maar", GEOLOGY, July 2017; v. 45; no. 7; p. 619–622, doi:10.1130/G39002.1

http://www.geosociety.org/datarepository/2017/2017202.pdf

&

Shakhova et al (2017), "Current rates and mechanisms of subsea permafrost degradation in the East Siberian Arctic Shelf", Nature Communications, doi: 10.1038/ncomms15872

https://www.nature.com/articles/ncomms15872

Very best,
ASLR

Edit: In order to better appreciate how 'consensus science' is still largely ignoring Hansen's numerous contributions to understanding climate change risks (such as his ice-climate feedback) this century, I provide the following linked open access draft paper:

Title: "Scientific Reticence: a DRAFT Discussion:

http://www.columbia.edu/~jeh1/mailings/2017/20171026_ScientificReticence.pdf
« Last Edit: November 06, 2017, 05:24:39 PM by AbruptSLR »
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A-Team

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Re: Arctic Methane Release
« Reply #482 on: November 06, 2017, 05:03:52 PM »
Quote
Assuming it's bad, getting worse and becoming significant soon: what to do?
That's a good question.

Better data: not nearly enough research resources are currently being allocated to the ESAS. This wouldn't affect outcome but would at least box in timing and magnitude better.

Shakhova makes a case for methane escape growing 'exponentially' rather than linearly. That could be a figure of speech or the solution to a differential equation: 'the rate of increase in methane release proportional to the current rate of methane release'.

Linear increases from slow thermal permafrost degradation could possibly be accommodated. However if the very establishment of a minor escape route leads to its physical enlargement to a major hotspot, and vigorous hotspot venting leads to explosive fountaining of regional pressurized gas stores, then the rate of methane release feeds on itself (by enlargement of the vent and conduit connectivity) and so goes up faster than linearly.

On the figure of speech side, Shakhova might just mean a whole lot more hotspots than last time they were out there. This might suggest permafrost degradation is crossing some kind of threshold across an ever-broader area. We may just happen to be here at an unfortunate one-off bad time in the late Holocene, perhaps compressed or partially brought on by anthropogenic warming.

Either way, modeling is delusional. It's all about the history and heterogeneity, for which sufficient detail will never be available. Nobody even has a talik count. Show me the scour map. Faults can be visualized at cm scale at km depth? Monitoring is all you can do.

Hope: there are a lot of steps between methane deep in the mud and methane in the greenhouse stratosphere, maybe some of them will slow or limit release to a rate that the atmosphere can accommodate.

Even in shallow water, only a fraction of the methane in bubbles actually reaches the atmosphere. That fraction rapidly increases with entrainment during rapid voluminous releases. The atmospheric half-life is fairly short, provided stratospheric hydroxyl radical supply is not overwhelmed.

Make room: reduce gratuitous greenhouse gas emissions as much as possible as soon as possible. That would include all the usual suspects such as coal and fugitive methane emissions.

The biggest single benefit with overnight effect and least societal inconvenience comes from cutting beef-belch methane (and its production-associated emissions). But banning beef because of emissions would about as popular as banning football because of concussions.

-/-/-/-/-/-/

There don't seem to be any remotely plausible geo-engineering options. Some of them seem so stupid, like laying down a giant tarp over a third of the Arctic Ocean, they aren't worth discussing. Drill and flare to CO2? How many decades have we been doing that without depleting Texas -- the ESAS is 3x the size. How much did Shell blow on just one Beaufort platform, five billion? Is there a single connected reservoir or a hundred thousand?

-/-/-/-/-/-/

Because IPCC dug themselves into such a hole with the slow CO2 narrative, they are in no position to pivot to methane. Methane is seen as a threat all right ... to their credibility. So 'policy-makers' will mainly hear methane being dissed, not that they would do anything if better informed.

Threat-proportionate action is not underway with CO2 today; even less will be done about methane as it touches two sacred western industries. Nothing can be done about ESAS methane emissions; it is wait-and-see how soon, how bad they'll get. We're not on track to make adequate headroom to accommodate even decadal-scale rapid release.
« Last Edit: November 06, 2017, 06:53:23 PM by A-Team »

sidd

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Re: Arctic Methane Release
« Reply #483 on: November 06, 2017, 06:16:28 PM »
"Hansen's ice-climate feedback mechanism that would drive large amounts of warm seawater into the Arctic Basin, particularly along the edge of the ESAS continental shelf."

Wait, what ? I am reading Hansen's papers right now, can tell me exactly where he says this ?

sidd

TerryM

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Re: Arctic Methane Release
« Reply #484 on: November 06, 2017, 06:23:31 PM »
If a solution is possible it requires somehow lowering the pressure, and volume, of the free gas buried within the ESAS. At this stage of our technology the only way to lower this pressure is to drill baby drill, then flare baby flare.


Do I think it will work - No
Do I think it will be attempted - No
Do I know of a better plan - No


Lance the boil under controlled conditions, then neutralize the poisonous emission.
Terry

A-Team

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Re: Arctic Methane Release
« Reply #485 on: November 06, 2017, 06:42:56 PM »
Quote
Wait, what? tell me exactly where Hansen says this ?
No idea. That would have been a decade prior to the first actual data from Oden's traverses of the ESAS shelf edge. There is little methane to be found there any more. Warm water along the edge of the ESAS continental shelf could not trigger substantial methane release if it's not there to begin with. There's only so far you can go with models not grounded on observational data.

Quote
Continental slopes north of the East Siberian Sea potentially hold large amounts of methane (CH4) in sediments as gas hydrate and free gas. Although release of this CH4 to the ocean and atmosphere has become a topic of discussion, the region remains sparingly explored. Here we present pore water chemistry results from 32 sediment cores taken during Leg 2 of the 2014 joint  SWERUS-C3 expedition. The cores come from depth transects across the slope and ... north of Wrangel Island and the New Siberian Islands. ...

These are among the first pore water results generated from this vast climatically sensitive region, and they imply that abundant CH4, including gas hydrates, do not characterize the East Siberian Sea slope or rise along the investigated depth transects. This contradicts previous modeling and discussions, which due to the lack of data are almost entirely based on assumption.

Lots of other interesting stuff in that same special issue of The Cryosphere with potential relevance to ESAS methane:

https://www.the-cryosphere.net/special_issue652.html

Deglacial sea level history of the East Siberian Sea and Chukchi Sea margins

Global sea level rise during the last deglacial flooded the Siberian continental shelf in the Arctic Ocean. Sediment cores, radiocarbon dating, and microfossils show that the regional sea level in the Arctic rose rapidly from about 12 500 to 10 700 years ago. Regional sea level history on the Siberian shelf differs from the global deglacial sea level rise perhaps due to regional vertical adjustment resulting from the growth and decay of ice sheets.


Post-glacial flooding of the Bering Land Bridge dated to 11 cal ka BP based on new geophysical and sediment records

The Arctic and Pacific oceans are connected by the presently ~53 m deep Bering Strait. During the last glacial period when the sea level was lower than today, the Bering Strait was exposed. Humans and animals could then migrate between Asia and North America across the formed land bridge. From analyses of sediment cores and geophysical mapping data from Herald Canyon north of the Bering Strait, we show that the land bridge was flooded about 11 000 years ago.


Ice-shelf damming in the glacial Arctic Ocean: dynamical regimes of a basin-covering kilometre-thick ice shelf

Recent data suggest that a 1 km thick ice shelf extended over the glacial Arctic Ocean during MIS 6, about 140 000 years ago. Here, we theoretically analyse the development and equilibrium features of such an ice shelf. The ice shelf was effectively dammed by the Fram Strait and the mean ice-shelf thickness was controlled primarily by the horizontally integrated mass balance. Our results can aid in resolving some outstanding questions of the state of the glacial Arctic Ocean.

The De Long Trough: a newly discovered glacial trough on the East Siberian continental margin

Ice sheets extending over parts of the East Siberian continental shelf have been proposed for the last glacial period and during the larger Pleistocene glaciations. The sparse data available over this sector of the Arctic Ocean have left the timing, extent and even existence of these ice sheets largely unresolved.

Here we present new geophysical mapping and sediment coring data from the East Siberian shelf and slope collected during the 2014 SWERUS-C3 expedition. Sub-bottom profiles reveal a set of glacial landforms that include grounding zone formations along the outer continental shelf, seaward of which lies a  >  65 m thick sequence of glacio-genic debris flows.

The glacial landforms are interpreted to lie at the seaward end of a glacial trough – the first to be reported on the East Siberian margin, here referred to as the De Long Trough because of its location due north of the De Long Islands. Stratigraphy and dating of sediment cores show that a drape of acoustically laminated sediments covering the glacial deposits is older than ∼ 50 cal kyr BP.

This provides direct evidence for extensive glacial activity on the Siberian shelf that predates the Last Glacial Maximum and most likely occurred during the Saalian, Marine Isotope Stage 6.
« Last Edit: November 06, 2017, 06:51:09 PM by A-Team »

Forest Dweller

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Re: Arctic Methane Release
« Reply #486 on: November 06, 2017, 07:13:03 PM »
Quote
Assuming it's bad, getting worse and becoming significant soon: what to do?
That's a good question.

Better data: not nearly enough research resources are currently being allocated to the ESAS. This wouldn't affect outcome but would at least box in timing and magnitude better.

Shakhova makes a case for methane escape growing 'exponentially' rather than linearly. That could be a figure of speech or the solution to a differential equation: 'the rate of increase in methane release proportional to the current rate of methane release'.

Linear increases from slow thermal permafrost degradation could possibly be accommodated. However if the very establishment of a minor escape route leads to its physical enlargement to a major hotspot, and vigorous hotspot venting leads to explosive fountaining of regional pressurized gas stores, then the rate of methane release feeds on itself (by enlargement of the vent and conduit connectivity) and so goes up faster than linearly.

On the figure of speech side, Shakhova might just mean a whole lot more hotspots than last time they were out there. This might suggest permafrost degradation is crossing some kind of threshold across an ever-broader area. We may just happen to be here at an unfortunate one-off bad time in the late Holocene, perhaps compressed or partially brought on by anthropogenic warming.

Either way, modeling is delusional. It's all about the history and heterogeneity, for which sufficient detail will never be available. Nobody even has a talik count. Show me the scour map. Faults can be visualized at cm scale at km depth? Monitoring is all you can do.

Hope: there are a lot of steps between methane deep in the mud and methane in the greenhouse stratosphere, maybe some of them will slow or limit release to a rate that the atmosphere can accommodate.

Even in shallow water, only a fraction of the methane in bubbles actually reaches the atmosphere. That fraction rapidly increases with entrainment during rapid voluminous releases. The atmospheric half-life is fairly short, provided stratospheric hydroxyl radical supply is not overwhelmed.

Make room: reduce gratuitous greenhouse gas emissions as much as possible as soon as possible. That would include all the usual suspects such as coal and fugitive methane emissions.

The biggest single benefit with overnight effect and least societal inconvenience comes from cutting beef-belch methane (and its production-associated emissions). But banning beef because of emissions would about as popular as banning football because of concussions.

-/-/-/-/-/-/

There don't seem to be any remotely plausible geo-engineering options. Some of them seem so stupid, like laying down a giant tarp over a third of the Arctic Ocean, they aren't worth discussing. Drill and flare to CO2? How many decades have we been doing that without depleting Texas -- the ESAS is 3x the size. How much did Shell blow on just one Beaufort platform, five billion? Is there a single connected reservoir or a hundred thousand?

-/-/-/-/-/-/

Because IPCC dug themselves into such a hole with the slow CO2 narrative, they are in no position to pivot to methane. Methane is seen as a threat all right ... to their credibility. So 'policy-makers' will mainly hear methane being dissed, not that they would do anything if better informed.

Threat-proportionate action is not underway with CO2 today; even less will be done about methane as it touches two sacred western industries. Nothing can be done about ESAS methane emissions; it is wait-and-see how soon, how bad they'll get. We're not on track to make adequate headroom to accommodate even decadal-scale rapid release.

Excellent analysis A-Team.
How about not drilling the Arctic like a Swiss cheese as well?
As you quoted Shakova in your above post:
"Numerous gas blowouts followed by long-lasting gas flow have been reported from permafrost areas disturbed by exploratory drilling in Siberia, both on-land and offshore. Such gas blowouts were reported from shallow permafrost-related gas-hydrate accumulations at depths of only a few tens of metres, starting from 20 m depth.

Offshore, a particularly powerful gas discharge erupting from a well drilled through the subsea permafrost was documented in the Pechora Sea shelf; a gas–water fountain originating from 50 m beneath the sediment surface in 64 m-deep water reached 10 m above the ship. Echo sounding carried out at the drilling site 10 days after this event revealed an underwater fountain ∼10 m in diameter, with a height ∼40 m above the sea floor."

That sort of stuff is very Bermuda Triangle-ish is it not and i'm sure the IPCC has never heard of it either.
I've seen several reports and video of a Chinese rig that sank due to methane release but cannot re-find any info unfortunately.
That may wake up a few people dozing off from all the CO2 vented at climate conferences...a picture is worth a thousand words they say.

TerryM

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Re: Arctic Methane Release
« Reply #487 on: November 06, 2017, 07:59:38 PM »



A small, but violent CH4 eruption in Southern Ontario. No gas lines in the area. No landfill sites.


The gas pushed through >20' of heavy clay to make it's way to freedom. If we ever get another real winter here I'll check the ice for methane pockets.
Terry

AbruptSLR

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Re: Arctic Methane Release
« Reply #488 on: November 06, 2017, 08:09:10 PM »
"Hansen's ice-climate feedback mechanism that would drive large amounts of warm seawater into the Arctic Basin, particularly along the edge of the ESAS continental shelf."

The statement above assumes that the WAIS might collapse abruptly this century.

In this regards, the following link leads to the University of Alaska Fairbank's website focused on Lake Elgygytgn research, and the extract following the link is from an article Posted on February 4th, 2014 by Laura Nielsen on "Inter-hemispheric climate coupling". The extract emphasizes that repeatedly paleo-collapses of the WAIS resulted in subsequent Arctic amplification, due both to changes in ocean currents (in keeping with Hansen's ice-climate feedback), and to increases in sea level pushing more warm Pacific water through the Bering St. into the Arctic Ocean.


http://frontierscientists.com/tag/lake-elgygytgyn/

Extract: "Antarctica and the Arctic
Climate at the North and South pole are connected. Sediment records from Antarctica show that the West Antarctic ice sheet melted at various times in history. Following many of those events, the Arctic warmed. These recurring intervals of paired warming show that climate in the two hemispheres is linked – it’s called inter-hemispheric climate coupling.

“When the West Antarctic ice sheet pulls back we see a corresponding warmth in the high latitudes again, probably affecting the size of the Greenland ice sheet with major implications for changes in sea level,” says Julie Brigham-Grette. “Our results mesh with what glaciologists are seeing today. Seven of the 12 major ice shelves around the Antarctic are melting or are gone. We suspect the tipping point for the gradual de-glaciation of Greenland and the Arctic may be lower than glaciologists once thought.”

Complex systems
Earth is a complicated place. We can’t explain past warming using only orbital dynamics or levels of Carbon Dioxide. Scientists affiliated with the project outlined some past events that might explain the rapid warming the sediment records show occurred in both Antarctica and the Arctic around similar times.

When you imagine Antarctica, the picture includes large ice shelves that hang off the rocky edge of the ice-covered continent. Normally that ice keeps nearby ocean water very cold. The cold water travels along currents toward the north Pacific where it wells up to the surface. Ocean circulation can be affected, though. If Antarctic ice sheets disintegrate or melt away, they no longer enforce cold water currents that journey to the Arctic. Instead, surface ocean waters in the Arctic become warmer.

When Antarctica’s ice sheets disintegrate the ocean gains more water and sea levels rise globally. The Bering Strait usually restricts how much warm surface water approaches the Arctic from the south, but higher sea levels would mean warm surface water didn’t have to squeeze through such a narrow space, letting more warm water past the Bering Strait into the Arctic Ocean.

Either way, a warmer ocean means higher temperatures and more rainfall for the Arctic, which impacts paleoclimatology and sea ice history. Grasping the climate connections between the hemispheres gives us insight into our near future."

Also, I seem to remember a reference with climate model results with freshwater hosing that also indicates that a collapse of the WAIS would push relatively warm Pacific water into the Arctic Basin, but I cannot remember where I posted this reference (after 13,000 plus posts my memory is getting jumbled).
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AbruptSLR

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Re: Arctic Methane Release
« Reply #489 on: November 06, 2017, 09:41:44 PM »
That would have been a decade prior to the first actual data from Oden's traverses of the ESAS shelf edge. There is little methane to be found there any more. Warm water along the edge of the ESAS continental shelf could not trigger substantial methane release if it's not there to begin with. There's only so far you can go with models not grounded on observational data.

While not specifically related to the ESAS, the 2012 article entitled: "Locked greenhouse gas in Arctic sea may be 'climate canary'"; Nature, doi:10.1038/nature.2012.11988; which discusses methane hydrates observed in the Canadian Beaufort Seafloor in as little as 290m of water depth:

http://www.nature.com/news/locked-greenhouse-gas-in-arctic-sea-may-be-climate-canary-1.11988

See also the associated article (from which the first attached image was taken) entitled: "Expedition to study methane gas bubbling out of the Arctic seafloor"

http://www.mbari.org/expedition-to-study-methane-gas-bubbling-out-of-the-arctic-seafloor/

Extract: "Paull’s work in the Arctic started in 2003, with an investigation into the enigmatic underwater hills called “pingo-like features” (PLFs) that rise out of the continental shelf of the Beaufort Sea. (Pingos are isolated conical hills found on land in some parts of the Arctic and subarctic.)
Over time, the focus of the team’s research has moved farther offshore, into deeper water. Their second expedition in 2010 looked at diffuse gas venting along the seaward edge of the continental shelf. The 2012 expedition will focus on three large gas-venting structures on the continental slope, at depths of 290 to 790 meters (950 to 2,600 feet)."

The second images illustrates how a hypothetical submarine landslide on the continental slope could release sufficient methane gas to reach the surface.  Probably the shallow water methane hydrates in the ESAS is of more concern, but the Clathrate Gun Hypothesis cannot be ignored in the Arctic Basin.
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AbruptSLR

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Re: Arctic Methane Release
« Reply #490 on: November 06, 2017, 09:56:31 PM »
Also, I seem to remember a reference with climate model results with freshwater hosing that also indicates that a collapse of the WAIS would push relatively warm Pacific water into the Arctic Basin, but I cannot remember where I posted this reference (after 13,000 plus posts my memory is getting jumbled).

I believe that the linked reference was the one that that I was thinking of that discusses how the collapse of the WAIS can alter oceanic and atmospheric patterns, leading to Super Interglacial conditions including marked northward ocean heat transport via the Pacific Ocean.  Also, I note that as the sea surface is higher in the Pacific than in the Atlantic, water flows from the Pacific into the Arctic Ocean through the Bering Strait:

Flavio Justino, Douglas Lindemann, Fred Kucharski, Aaron Wilson, David Bromwich, and Frode Stordal (2017), "Oceanic response to changes in the WAIS and astronomical forcing during the MIS31 superinterglacial", Clim. Past, 13, 1081–1095, https://doi.org/10.5194/cp-13-1081-2017

https://www.clim-past.net/13/1081/2017/cp-13-1081-2017.pdf

Abstract: "Marine Isotope Stage 31 (MIS31, between 1085 and 1055 ka) was characterized by higher extratropical air temperatures and a substantial recession of polar glaciers compared to today.  Paleoreconstructions and model simulations have increased the understanding of the MIS31 interval, but questions remain regarding the role of the Atlantic and Pacific oceans in modifying the climate associated with the variations in Earth’s orbital parameters. Multi-century coupled climate simulations, with the astronomical configuration of the MIS31 and modified West Antarctic Ice Sheet (WAIS) topography, show an increase in the thermohaline flux and northward oceanic heat transport (OHT) in the Pacific Ocean.  These oceanic changes are driven by anomalous atmospheric circulation and increased surface salinity in concert with a stronger meridional overturning circulation (MOC). The intensified northward OHT is responsible for up to 85% of the global OHT anomalies and contributes to the overall reduction in sea ice in the Northern Hemisphere (NH) due to Earth’s astronomical configuration. The relative contributions of the Atlantic Ocean to global OHT and MOC anomalies are minor compared to those of the Pacific.  However, sea ice changes are remarkable, highlighted by decreased (increased) cover in the Ross (Weddell) Sea but widespread reductions in sea ice across the NH."

Extract: "Based on coupled climate simulations performed under present day and boundary conditions representative of Marine Isotope Stage 31 (MIS31), our analyses provide evidence that under MIS31 climate conditions there was a remarkable reduction in sea ice distribution across the NH due to the astronomical configuration of that epoch. This contrasts with increases in sea ice area across the SH. The climate response to collapsing the WAIS is prominent in the vicinity of the Antarctic continent, whereas the effect of modification in the Earth orbital configuration extends worldwide.

It has furthermore been demonstrated that the MIS31 interglacial experienced significant changes in the Meridional Overturning Circulation (MOC). In the Atlantic, increases in the MOC are related to an intensified westerly atmospheric flow in the northern North Atlantic, leading to strong convective mixing. The main convection sites in MIS31 have also been shifted poleward compared to the control simulation (CTR) in concert with changes in the position of the meridional thermal gradient."

Also, it would be nice if anyone attending the Fall AGU Meeting in New Orleans could report back on:

Julie Brigham-Grette, Robert M Deconto, Rajarshi Roychowdhury, Greg de Wet, Benjamin Andrew Keisling, Martin Melles and Pavel Minyuk (2017), "Too Warm, Two Poles: Super Interglacial Teleconnections and Possible Dual Pole Ice Sheet Stability", AGU Fall Meeting
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sidd

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Re: Arctic Methane Release
« Reply #491 on: November 06, 2017, 10:14:01 PM »
I too have seen papers positing increased flow thru Bering with higher sea level. Now in Hansen(2016, doi:10.5194/acp-16-3761-2016 ) , the closest mention  I find is that his ocean model (Russell, 1995, nice paper) shows "Mixing reaching the ocean floor on the Siberian coast in our model (Fig 19) may be realistic as coastal polynya are observed on the Siberian continental shelf"  [in winter], but that is present day climate.  But i see nothing positing a surge of warm water into ESAS in future in the simulations where there is only freshwater hosing in the south. And his freshwater hosing suppresses meridonal overturning circulation so there is a difference between hs model and the Justino model for he says nothing about increased northward heat transport in the Pacific.

sidd

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Re: Arctic Methane Release
« Reply #492 on: November 06, 2017, 10:57:33 PM »
Upon reading the Justino paper (and the Justino 2015 paper) i see some reasons why he differs from Hansen. First off he doesnt change salinity due to WAIS collapse and he has no freshwater hosing.

" ... changes in the initial salinity field in response to the WAIS collapse have not been included."

Here he follows authors that argue that " ... an outflow rate associated with WAIS melting is
not realistically attainable ..."

I have some other quibbles with the Justino paper as well, but those can wait.

sidd


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Re: Arctic Methane Release
« Reply #493 on: November 06, 2017, 11:50:09 PM »
sidd,

It is not my intent to say that Hansen et al 2016 (doi:10.5194/acp-16-3761-2016) specifically cites that warm Pacific water will increasingly flow thru the Bering Strait to destabilize ESAS methane hydrates as part of his ice-climate feedback mechanism.  Nevertheless, as I understand this mechanism, during a potential collapse of the WAIS, this would cause an increase in Antarctic sea ice extent and a reduction in the production of AABW (Antarctic Bottom Water); which slows down the MOC, which increases the tropical sea surface temperature, which both increases the strength of El Ninos (which advects atmospheric heat from the tropical Pacific to both West Antarctica and the Arctic) but also increases the temperature of the Gulf Stream waters, which pushes more warm water via the AMOC into the North Atlantic.  With both the atmospheric advection and the Gulf Stream oceanic advection contributing to bipolar seesaw (i.e. a collapse of the WAIS would cool the Southern Ocean while warming the Arctic Ocean).

Regarding the bipolar seesaw mechanism inherent in Hansen's ice-climate mechanism, the Last Glacial Termination, LGT, occurred from 18,000 to 11,650 kya, and the following reference, reconstructs the dynamic response of the Antarctic ice sheets to warming in this period in order to better evaluate Hansen's ice-climate feedback mechanisms.  The abstract from the linked reference concludes: "Given the anti-phase relationship between inter-hemispheric climate trends across the LGT our findings demonstrate that Southern Ocean-AIS feedbacks were controlled by global atmospheric teleconnections.  With increasing stratification of the Southern Ocean and intensification of mid-latitude westerly winds today, such teleconnections could amplify AIS mass loss and accelerate global sea-level rise."

Fogwill, et. al. (2017), "Antarctic ice sheet discharge driven by atmosphere-ocean feedbacks at the last Glacial Termination", Scientific Reports 7, Article number 39979, doi:10.1038/srep39979

https://www.nature.com/articles/srep39979

See also the associated article entitled: "How Antarctic ice melt can be a tipping point for the whole planet’s climate"

https://theconversation.com/how-antarctic-ice-melt-can-be-a-tipping-point-for-the-whole-planets-climate-83776

Extract: "To explore how melting Antarctic ice might cause such dramatic change in the global climate, we used a climate model to simulate the release of large volumes of freshwater into the Southern Ocean. The model simulations all showed the same response, in agreement with our climate reconstructions: regardless of the amount of freshwater released into the Southern Ocean, the surface waters of the tropical Pacific nevertheless warmed, causing changes to wind patterns that in turn triggered the North Atlantic to warm too."

To me it seems clear that the bipolar seesaw mechanism incorporates major portions of Hansen's ice-climate feedback mechanism, and as the first attached image of the SLR fingerprint effect from the loss of the WAIS unit ice mass this includes a deepening of the water depth of the Bering Strait and increased flow of relatively warm Pacific Ocean water into the Arctic Ocean Basin (including in the ESAS area).

Best,
ASLR

Edit: For what it is worth, I attach the second image that illustrates the atmospheric bridge that advects heat from the Tropical Pacific to the North Pacific.
« Last Edit: November 07, 2017, 12:26:39 AM by AbruptSLR »
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gerontocrat

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Re: Arctic Methane Release
« Reply #494 on: November 07, 2017, 05:03:07 PM »
For those, like me, who are very shaky on the science of it all I recommend the following article by  Jenny Griffin.

https://www.climateemergencyinstitute.com/uploads/Ocean_Acidification___Methane.pdf

There is a really good section on the basic science of what methane hydrates are and how they are formed, and then goes on to discuss methane hydrate stability, and what happens when hydrates melt. New to me was the crucial importance of bacteria.

"Most of the methane that is released is expected to be broken down by
bacteria as it rises up through the ocean sediments and through the water column before it
reaches the surface of the ocean.
The decomposition of methane occurs at the result of
two biological processes:
• anaerobic oxidation of methane by bacteria in the sediments of the ocean floor
• aerobic oxidation of methane by bacteria in the water column. "

In particular aerobic decomposition involves the same chemical reaction as burning methane, i.e.

CH4 + 2 O2 → CO2 + 2 H2O

The result is not good ;-

"Aerobic Oxidation: When methane is broken down aerobically by bacteria in the water
column they use oxygen to facilitate the process, producing carbon dioxide which
dissolves in the seawater. This process negatively impacts marine environment in two
ways:
1. Carbon dioxide promotes ocean acidification.
2. Aerobic oxidation of methane utilizes oxygen within the water column which could
result in the expansion of oxygen depleted zones across the ocean. Oxygen
depletion can result in mass mortalities of marine organisms – oxygen poor zones
are unable to support animals that need oxygen for survival and are thus typically
devoid of marine life.

Previous posts on this thread talked about bacterial decomposition of methane in shallow water near Svalbard. I wonder if oxygen depletion was noted.

The article then refers to rapid methane release in shallow water - i.e. the ESAS scenario.

One final quote ;-
"Mass Extinction Event
Even more alarming is that if ocean acidification is left unchecked it could potentially
initiate a Great Mass Extinction Event, as there is increasing evidence pointing to high
atmospheric carbon dioxide concentrations and rapidly acidifying oceans having triggered
four of the previous five Great Mass Extinctions.
Based on geological records it can be assumed that hydrates have broken down on a
large scale numerous times in the Earth’s history, leading to extreme global warming and
massive extinctions of organisms on the sea floor and beyond."

I have saved this article as it is just the sort of thing to educate those who want to know and those who do not.
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AbruptSLR

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Re: Arctic Methane Release
« Reply #495 on: November 07, 2017, 06:29:29 PM »
gerontocrat,

Thanks for raising some more examples of some of the right-tailed risk and consequence of potential future Arctic Methane Release.  While it is human nature (including that of reticent scientists) to limit (or to break-down) complex problems to ones of a more manageable degree of complexity; in the real world of climate consequences it is inappropriate for consensus climate science to ignore such right-tailed risks, therefore, I add discussion of two more right tailed risks associated with Arctic Methane Release (which is not limited to an abrupt release of methane from ESAS hydrates):

1. Synergy between different mechanisms supporting Arctic Amplification can accelerate the timing of Arctic Methane Releases, by progressively ratcheting up the regional climate state. In this regards, the linked article indicates that current climate models do not yet know how to correctly model the observed effects of local rapid warming (see the first attached image & the following extract):

Title: "Understanding Causes and Effects of Rapid Warming in the Arctic"

https://eos.org/project-updates/understanding-causes-and-effects-of-rapid-warming-in-the-arctic

Extract: "Although many individual consequences of changes in these Arctic climate parameters are known, their combined influence and relative importance for Arctic amplification are complicated to quantify and difficult to disentangle. As a result, there is not yet a consensus in the Arctic research community about the dominant mechanisms leading to the phenomenon of Arctic Amplification."

&

2. Furthermore, per the following reference circa 2050 methane emissions from thermokarst lake activity could become important (assuming continued aggressive warming), see the second attached image:

Schneider von Deimling, T., Grosse, G., Strauss, J., Schirrmeister, L., Morgenstern, A., Schaphoff, S., Meinshausen, M., and Boike, J.: Observation-based modelling of permafrost carbon fluxes with accounting for deep carbon deposits and thermokarst activity, Biogeosciences, 12, 3469-3488, doi:10.5194/bg-12-3469-2015, 2015.

http://www.biogeosciences.net/12/3469/2015/bg-12-3469-2015.html

Best,
ASLR
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TerryM

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Re: Arctic Methane Release
« Reply #496 on: November 07, 2017, 11:51:56 PM »
My reading of S&S is that they see the free gas below the hydrates as by far the greater problem that faces us, hydrates or clathrates making up only a small percentage of the ESAS's sequestered methane.
Terry

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Re: Arctic Methane Release
« Reply #497 on: November 08, 2017, 04:27:20 PM »
My reading of S&S is that they see the free gas below the hydrates as by far the greater problem that faces us, hydrates or clathrates making up only a small percentage of the ESAS's sequestered methane.
Terry

Terry,

Thanks for highlighting this important point.  While currently most free gas, and hydrate methane, seeps from the Arctic seafloor are absorbed by microbes near the seafloor and in the water (see the first image); this situation could markedly change before the end of this century due to local mechanisms some of which are illustrated in the second attached image.  Local breaches (or chimneys) through an impermeable hydrate cap over free gas reservoirs could release large volumes of methane gas (which may be too much for the microbes to consume) without fully decomposing the hydrate cap.  Such future breaches could be due to such mechanisms as: 1. local submarine landslides in the continental slope; 2. decomposition of local methane hydrate plugs over pre-existing chimneys; 3. Local erosion; etc.

Modeling such potential nonlinear behavior is difficult, but noting the possibility of such behavior in the executive summary to decision makers is not.

Best,
ASLR

Edit: I neglected to mention that subsea pingos (see the third image and linked article) can also serve as chimneys through a hydrate cap to release previously trapped free gas.

Title: "Methane feeds subsea ice mounds off Siberia"

Extract: "Pingos are spectacular landforms associated with permafrost in the Arctic. They are circular or elliptical formations protruding from the level ground of the tundra, and can be up to 60 meters high. In essence, they are huge lumps of ice covered with soil. Similar structures are now found strewn on the ocean floor in the Arctic shallow seas."
https://www.sciencedaily.com/releases/2015/11/151117092247.htm
« Last Edit: November 08, 2017, 04:34:21 PM by AbruptSLR »
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AbruptSLR

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Re: Arctic Methane Release
« Reply #498 on: November 09, 2017, 07:19:52 PM »
Due to warmer spring conditions, methane from high latitude boreal peat landscapes should increase with continued global warming:

Manuel Helbig, William L Quinton and Oliver Sonnentag (8 November 2017), "Warmer spring conditions increase annual methane emissions from a boreal peat landscape with sporadic permafrost", Environmental Research Letters, Volume 12, Number 11,  https://doi.org/10.1088/1748-9326/aa8c85

http://iopscience.iop.org/article/10.1088/1748-9326/aa8c85/meta;jsessionid=BDEA4F6AFC6803F55D48309D93BFA2B5.c3.iopscience.cld.iop.org

Abstract: "About a fifth of the global wetland methane emissions originate from boreal peatlands, which represent an important land cover type in boreal landscapes in the sporadic permafrost zone. There, rising air temperatures could lead to warmer spring and longer growing seasons, changing landscape methane emissions. To quantify the effect of warmer spring conditions on methane emissions of a boreal peat landscape in the sporadic permafrost zone of northwestern Canada, we analyzed four years (2013–2016) of methane fluxes measured with the eddy covariance technique and long-term (1951–2016) meteorological observations from a nearby climate station. In May, after snowmelt was complete, mean air temperatures were more than 2 °C warmer in 2013, 2015, and 2016 than in 2014. Mean growing season (May–August) air temperatures, in contrast, differed by less than 1 °C over the four years. Warmer May air temperatures caused earlier wetland soil warming, with temperatures rising from ~0 °C to >12 °C 25 to 40 days earlier and leading to ~6 °C warmer mean soil temperatures between May and June. However, from July to August, soil temperatures were similar among years. Mean May to August and annual methane emissions (6.4 g CH4 m−2 and 9.4 g CH4 m−2, respectively) of years with warmer spring (i.e. May) temperatures exceeded emissions during the cooler year by 20%–30% (4.5 g CH4 m−2 and 7.2 g CH4 m−2, respectively). Among years with warmer springs, growing season methane emissions varied little (±0.5 g CH4 m−2). The observed interannual differences are most likely caused by a strong soil temperature control on methane fluxes and large soil temperature differences during the spring. Thus, in a warming climate, methane emissions from waterlogged boreal peat landscapes at the southern limit of permafrost are likely to increase in response to more frequent occurrences of warm springs."
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AbruptSLR

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Re: Arctic Methane Release
« Reply #499 on: November 11, 2017, 01:23:41 AM »
The Mid-Brunhes Event (MBE) coincides with MIS 11 (the Holsteinian) about 400,000 to 350,000 years ago, and marks a major transition to subsequent enhanced Arctic Amplification as discussed in the open access linked reference (see the first three attached images while the fourth image from another source help to clarify that after the MBE interglacial peak global mean peak temperatures have been higher).  Furthermore, the reference associates this change with the bipolar seesaw and episodic collapses of the WAIS.  This research clearly associates the bipolar seesaw mechanism with Hansen's ice-climate feedback and with Arctic Amplification.  This also implies that if the WAIS collapses this century (which DeConto and Pollard project will happen before the GMSTA gets to 2.7C), that warm Atlantic water will penetrate deep into the Arctic Ocean Basin, where it would likely have an impact on any shallow methane hydrates:

Cronin et al (2017), "Enhanced Arctic Amplification Began at the Mid-Brunhes Event ~400,000 years ago", Scientific Reports 7, Article No. 14475, doi: 10.1038/s41598-017-13821-2

https://www.nature.com/articles/s41598-017-13821-2

Extract: "Enhanced Arctic amplification at the MBE suggests a major climate threshold was reached at ~400 ka involving Atlantic Meridional Overturning Circulation (AMOC), inflowing warm Atlantic Layer water, ice sheet, sea-ice and ice-shelf feedbacks, and sensitivity to higher post-MBE interglacial CO₂ concentrations.

Southern Hemisphere ocean-atmosphere-sea ice processes are critical for understanding the MBE, specifically the idea that there is a bipolar seesaw operating between Northern and Southern Hemispheres on millennial timescales explain warmer interglacial condition in the Southern Hemisphere.  Barker et al. (2011) demonstrated that abrupt millennial-scale AMOC variability characterized the last 800 ka, albeit without the large amplitude shift seen in our Arctic records.  Holden et al. proposed a role for decreased stability of the West Antarctic Ice Sheet following the MBE, leading to AMOC slowdown during deglacials.  Thus, it is possible that ice sheet/ice shelf instability characterized both hemispheres providing the necessary non-linear dynamics to explain large amplitude temperature events in the Arctic Ocean.  However establishing the relationship between bottom temperature, sea ice and productivity during stadial and interstadial periods – require better sediment core resolution in the Arctic.  Nonetheless, the large shift in Arctic land ice, ice shelves and sea ice at the MBE, suggests an amplification of Arctic climate sensitivity related to higher interglacial CO₂ concentrations and associated feedbacks involving ice shelves and ice sheets, Heinrich-like events, AMOC-forcing Arctic Ocean temperature oscillations, and deeper submergence of Atlantic water in the central Arctic Basin."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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