Arctic Methane Release

[Serrara Fluttershy]

Thanks, a girl like me needs to poke my head into communities across the world every once in a while. (And I knew you'd say that  )
So to summarize; the threat in the ESAS is methane release from decomposed lifeforms across its seabed, in contrast to the media's common fingerpointing at the clathrates - and the entire plane of sediment is at risk of releasing catastrophic amounts of methane which has been building up below the surface for around 8 millennia?

[oren]

Welcome.
I think that methane is already releasing as we speak. IMHO it's not a one-time catastrophe/gun/boom but an ongoing problem that will only grow over time. At some point stopping humanity's emissions will not help as much as we think it might.

[kassy]

You summarize it pretty well. Would have made a damn fine executive summary...

[Serrara Fluttershy]

For my first post on this forum that's really thoughtful of you...honestly I was expecting someone to say that I derived incorrect conclusions.

[solartim27]

The good news is that this is self limiting, in that as the glacier melts away, the conditions to release the methane break down.  As the current equivalent is cow's, this source equals 136,000.

https://phys.org/news/2018-11-volcanoes-glaciers-combine-powerful-methane.amp

At Sólheimajökull when the meltwater reaches the glacier bed, it comes into contact with gases produced by the Katla volcano. These gases lower the oxygen content of the water, meaning some of the methane produced by the microbes can be dissolved into the water and transported out of the glacier without being converted to CO2.

Dr. Hugh Tuffen, a volcanologist at Lancaster University and co-author on the study, said: "The heat from Katla volcano may greatly accelerate the generation of microbial methane, so in fact you could see Katla as a giant microbial incubator./quote]

[Cid_Yama]

During the Sangamon interglacial, rivers flowed north into the Arctic dumping organic material onto the shelves. At the start of the last glacial, ice dams formed, forcing the rivers to flow south. The sea level in the Arctic dropped exposing the shelves. The shelves remained exposed throughout the last glacial, and as the Holocene began, glacial meltwater turned the shelves first into a wetland, then with the rise of sea level, the shelves were submerged.

The permafrost that formed throughout the last glacial began to degrade even before the shelves were submerged as thermokarst lakes and rivers formed taliks. Much like is happening to terrestrial permafrost today.

Once submerged, the new warmer subsea environment, the salinity (think what happens when you put salt on a frozen doorstep), and geothermal flux from below, worked over the last 8,000 years to degrade the permafrost to the point that it now is pourous, and even totally gone in places, over an area of 2 million sq km.

Much of the methane hydrates that formed over the last 100,000 years since the Sangamon, dissociated, leaving a large reservoir of free methane gas under pressure, prevented from releasing only by the layer of permafrost which until now had acted as a cap.

Since the shelf is on average about 50 meters deep, any methane released does not interact with the water column, but releases directly to the atmosphere.

This is the end result of a geological process that has been going on for thousands of years and is a part of a natural cycle.

Over the last decade, the size of the areas releasing methane has increased and the amount being released has accelerated.

The release of just 1% of the available free methane on the shelf is enough to cause catastrophic warming.

Since there is no way to refreeze the degrading permafrost cap, the methane release is inevitable.  There is no way to shut it off.  And the methane will continue to release until there is no more left to release.   

Whoever is questioning the decades of observations and research conducted by Semiletov and Shakhova haven't got a clue.  Semiletov is the head of the far eastern branch of the Russian Academy of Sciences.  Dozens of scientists have participated in this research.   

If you have research papers providing rebuttal to their work, post it.

Just saying "some people say" doesn't cut it around here.
 
Here, we present research papers and discuss them.         

   

[gerontocrat]

Lovely post, Cid_Yama.

If it wasn't for ASIF I would not have followed the links to the papers and learnt that which before I knew nothing about at all.

Problem is, I gather that as far as IPCC is concerned, it is one of those "known unknowns". As a result, I understand it does not figure in the IPCC climate change projections (while cow-farts are?), even though I believe the methane release will, sooner or later, invalidate those projections.

[Serrara Fluttershy]

During the Sangamon interglacial, rivers flowed north into the Arctic dumping organic material onto the shelves. At the start of the last glacial, ice dams formed, forcing the rivers to flow south. The sea level in the Arctic dropped exposing the shelves. The shelves remained exposed throughout the last glacial, and as the Holocene began, glacial meltwater turned the shelves first into a wetland, then with the rise of sea level, the shelves were submerged.

The permafrost that formed throughout the last glacial began to degrade even before the shelves were submerged as thermokarst lakes and rivers formed taliks. Much like is happening to terrestrial permafrost today.

Once submerged, the new warmer subsea environment, the salinity (think what happens when you put salt on a frozen doorstep), and geothermal flux from below, worked over the last 8,000 years to degrade the permafrost to the point that it now is pourous, and even totally gone in places, over an area of 2 million sq km.

Much of the methane hydrates that formed over the last 100,000 years since the Sangamon, dissociated, leaving a large reservoir of free methane gas under pressure, prevented from releasing only by the layer of permafrost which until now had acted as a cap.

Since the shelf is on average about 50 meters deep, any methane released does not interact with the water column, but releases directly to the atmosphere.

How much methane would this end up releasing?

[oren]

Great summary Cid_Yama. There is one thing that could refreeze the permafrost - a new ice age. Had humanity not affected the climate, the Earth might have been sliding into another cooling period which eventually might have stopped the ESAS methane release.

[wdmn]

Makes it sound like it doesn't matter what we do, we can't avoid the runaway greenhouse effect. All we can do is have a little bit of influence on how soon it happens.

[Cid_Yama]

Great summary Cid_Yama. There is one thing that could refreeze the permafrost - a new ice age. Had humanity not affected the climate, the Earth might have been sliding into another cooling period which eventually might have stopped the ESAS methane release.

You are probably correct.  Since Semiletov only first noticed the releases in 2003, and had been studying the shelf since 1993, in the normal cycle there would probably have been only limited releases before we entered a new glacial. 

We deviated from the normal cycle with the advent of agriculture and irrigation.  In a sense, civilization itself, was the cause.

When we switched from nomadic hunter-gatherers, few in numbers, to sedentary farmers, producing surplus grain, we set the process in motion.

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Which is why world leaders go through the motions, but put all their effort into maintaining BAU as long as possible.

If the world were going to end tomorrow, they would still want you to pay your bills and show up for work today.

The immediate threat is the day that stops happening.

 

[Cid_Yama]

During the Sangamon interglacial, rivers flowed north into the Arctic dumping organic material onto the shelves. At the start of the last glacial, ice dams formed, forcing the rivers to flow south. The sea level in the Arctic dropped exposing the shelves. The shelves remained exposed throughout the last glacial, and as the Holocene began, glacial meltwater turned the shelves first into a wetland, then with the rise of sea level, the shelves were submerged.

The permafrost that formed throughout the last glacial began to degrade even before the shelves were submerged as thermokarst lakes and rivers formed taliks. Much like is happening to terrestrial permafrost today.

Once submerged, the new warmer subsea environment, the salinity (think what happens when you put salt on a frozen doorstep), and geothermal flux from below, worked over the last 8,000 years to degrade the permafrost to the point that it now is pourous, and even totally gone in places, over an area of 2 million sq km.

Much of the methane hydrates that formed over the last 100,000 years since the Sangamon, dissociated, leaving a large reservoir of free methane gas under pressure, prevented from releasing only by the layer of permafrost which until now had acted as a cap.

Since the shelf is on average about 50 meters deep, any methane released does not interact with the water column, but releases directly to the atmosphere.

How much methane would this end up releasing?

I've seen an estimate by Russian researchers that the release of 1% of the available free methane on the shelf would raise atmospheric methane concentrations to 6 ppm (we are currently at 1.8 ppm) and raise global temperatures by 6 C.

Since warm-blooded mammals (including us) are at the upper level of our ability to lose metabolic heat already, this would be fatal.  We won't be around to care about the rest of it.     

[wdmn]

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Which is why world leaders go through the motions, but put all their effort into maintaining BAU as long as possible.

If the world were going to end tomorrow, they would still want you to pay your bills and show up for work today.

The immediate threat is the day that stops happening.

Just wondering how much consensus there is on this, since accepting it as true changes everything. I gather that the catch is we have no idea when this will happen, or how quickly...

If this is true, then why are so many people on this forum talking about policy solutions, and how to get better politicians into office? Why are scientists publishing papers warning about climate thresholds, if there's no way to avoid a hothouse earth?

I find it all very disingenuous, and the result is that I don't want to trust anyone on anything, put my energy into advocating for anything, or really do anything other than to tell all humans to fuck off for being such pieces of shit.

[aperson]

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Which is why world leaders go through the motions, but put all their effort into maintaining BAU as long as possible.

If the world were going to end tomorrow, they would still want you to pay your bills and show up for work today.

The immediate threat is the day that stops happening.

Just wondering how much consensus there is on this, since accepting it as true changes everything. I gather that the catch is we have no idea when this will happen, or how quickly...

If this is true, then why are so many people on this forum talking about policy solutions, and how to get better politicians into office? Why are scientists publishing papers warning about climate thresholds, if there's no way to avoid a hothouse earth?

I find it all very disingenuous, and the result is that I don't want to trust anyone on anything, put my energy into advocating for anything, or really do anything other than to tell all humans to fuck off for being such pieces of shit.

I'm trying to find a relevant quote from Shakhova but not having luck atm (I think it may be video not print). Essentially, it comes down to methane releases from the gas hydrate stability zone having "exponential uncertainty" not linear uncertainty. e.g. we're not concerned about 100 vs 200 vs 300 MT of carbon released as methane, we're concerned with whether it's 100 MT or 1 GT or 10 GT etc.... This spread of uncertainty cannot currently be constrained with available methods and research, and it's hard to square away with IPCC's emission pathways when the uncertainty bounds are between "significant but manageable impacts to global mean surface temperature" and "dominating the overall warming fingerprint"

[gerontocrat]

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Just wondering how much consensus there is on this, since accepting it as true changes everything. I gather that the catch is we have no idea when this will happen, or how quickly...

If this is true, then why are so many people on this forum talking about policy solutions, and how to get better politicians into office? Why are scientists publishing papers warning about climate thresholds, if there's no way to avoid a hothouse earth?

How much consensus? There is not a lot amongst the scientific establishment. Back in the day the majority of scientists thought Hansen was talking rubbish. Back in the 50's/early 60's most geologists thought plate tectonics was impossible - continents moving? daft idea!".Heavier than air flying machines? Hrrrmph.

So what does one do? I encourage my daughter to learn how to survive in a world where BAU has crashed. She knows herbs and foods, she knows a lot of anatomy, physiology and pathology etc etc etc.
Being relatively poor helps - scratching around for a living is good practice for what is to come.

Off-topic, so I stop.

[wdmn]

Thank you gerontocrat and aperson.

how much consensus?

I guess I even just wonder around here. Obviously there are those on the forum who still think that it's worth doing whatever they can to try to bring about larger societal change. It just seems like that is a strange response if you know that even going to zero emissions tomorrow wouldn't be enough to avoid complete calamity.

Do you advise your daughter to be poor?

Edit: I know I'm going off topic here, but just to be clear, death is not the problem here, the problem is complete loss of trust, and therefore loss of truth, therefore loss of science.

[oren]

I've seen an estimate by Russian researchers that the release of 1% of the available free methane on the shelf would raise atmospheric methane concentrations to 6 ppm (we are currently at 1.8 ppm) and raise global temperatures by 6 C.

Cid_Yama, this defies my intuition (an admittedly poor tool when discussing such stuff). A science reference would most welcome. Just off the cuff, as methane has a very short residence time, this 1% would have to be released in one huge burp, I would assume. Having it release over a thousand years will have much less of an effect, wouldn't it?
Also, can anyone here provide some calculation or number as to the radiative forcing should methane indeed rise to 6 ppm? Just to help figure if this makes any sense.

[TerryM]

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Which is why world leaders go through the motions, but put all their effort into maintaining BAU as long as possible.

If the world were going to end tomorrow, they would still want you to pay your bills and show up for work today.

The immediate threat is the day that stops happening.

Just wondering how much consensus there is on this, since accepting it as true changes everything. I gather that the catch is we have no idea when this will happen, or how quickly...

If this is true, then why are so many people on this forum talking about policy solutions, and how to get better politicians into office? Why are scientists publishing papers warning about climate thresholds, if there's no way to avoid a hothouse earth?

I find it all very disingenuous, and the result is that I don't want to trust anyone on anything, put my energy into advocating for anything, or really do anything other than to tell all humans to fuck off for being such pieces of shit.

wdmn
Some of us here have been following S&S at least since 2010/2011 and have been convinced of the validity of their research for what seems like a very long time.


To the best of my knowledge there is no way to pinpoint when the ESAS releases begin in earnest, no way to halt or mitigate the damage, and no way to escape, nor a place to escape to. If civilization were a patient, palliative care is the best that can be hoped for.
While I don't believe that anything can be done to delay the coming catastrophe. I do believe that some paths will spur on the process, some paths will exacerbate the pain of this terminal phase of our society, and at least one other path could kill us off before the clouds of methane are released.


I prefer the drawn out uncertainty that S&S's research posits to the sudden blasts and subsequent nuclear winter offered by so many of the political establishment. I'd prefer to put off the inevitable for as long as possible, rather than rushing full tilt into the abyss.


I'm 72 and recently released from what could easily have been a terminal hospital stay. If I were a healthy 20 year old raising a child I might view things from a different perspective. - but I don't think so.


Despair is a necessary stage in arriving at acceptance, try to move through it as rapidly as possible.


All my Best
Terry

[sidd]

Re: methane

Archer treated the case of 200GT release, found it's roughtly equivalent to 750 ppm CO2, 5w/m^2

http://www.realclimate.org/index.php/archives/2012/01/an-online-model-of-methane-in-the-atmosphere/

sidd

[sidd]

I think one of the biggest arguments against large scale methane spikes is the absence of isotopic evidence in the ice cores. Why don't we see evidence of methane in the Eemian (where we are, temperature wise, roughly) or MIS 11 ?

sidd

[oren]

Thank you sidd.

[bbr2314]

I think one of the biggest arguments against large scale methane spikes is the absence of isotopic evidence in the ice cores. Why don't we see evidence of methane in the Eemian (where we are, temperature wise, roughly) or MIS 11 ?

sidd

I would think the answer to this is because when extant ice sheets are in existence, any rapid methane release triggers freshwater release / +warming / +H2O / higher albedo, which ends up resealing the beast before it can contribute any significant amount. I would think the same thing will happen with the current event, maybe it will be worse than normal, but we won't be around anyways because it isn't the 1% release of the area's methane that kills everything, it is rapid cooling due to the negative feedbacks associated with ^ which occurs as the release starts to get going in any substantial capacity (IMO). We have historical evidence for these very rapid drops in Greenland temperatures and coincidentally or not, 2018 has seen Greenland's coldest November temp on record (or was it October)?

In any case, the rapid warming due to methane release probably stops when sea ice is sufficient to re-stabilize the shelves, which probably happens when continental albedo begins spiraling. That may still be a decade or two from now, but IMO we are quickly heading there.

So, good news: it isn't the methane that will kill everyone!
Bad news: the negative feedbacks that result from methane release are more than sufficient to get the job done, and occur well before any substantial % of methane is released, giving us even less time than in a clathrate-gun scenario.

Doom! 

[Wherestheice]

I think one of the biggest arguments against large scale methane spikes is the absence of isotopic evidence in the ice cores. Why don't we see evidence of methane in the Eemian (where we are, temperature wise, roughly) or MIS 11 ?

sidd

Big methane burps might have happened very abruptly in the past. As most know, methane only lasts for about 13 years or whatever until it turns into co2. This could be a good explanation for why the evidence is lacking in ice cores. It happens so fast it becomes undectable. Silent killer, just like the old grandpa farting at the dinner table tonight

[Wherestheice]

I think one of the biggest arguments against large scale methane spikes is the absence of isotopic evidence in the ice cores. Why don't we see evidence of methane in the Eemian (where we are, temperature wise, roughly) or MIS 11 ?

sidd

I would think the answer to this is because when extant ice sheets are in existence, any rapid methane release triggers freshwater release / +warming / +H2O / higher albedo, which ends up resealing the beast before it can contribute any significant amount. I would think the same thing will happen with the current event, maybe it will be worse than normal, but we won't be around anyways because it isn't the 1% release of the area's methane that kills everything, it is rapid cooling due to the negative feedbacks associated with ^ which occurs as the release starts to get going in any substantial capacity (IMO). We have historical evidence for these very rapid drops in Greenland temperatures and coincidentally or not, 2018 has seen Greenland's coldest November temp on record (or was it October)?

In any case, the rapid warming due to methane release probably stops when sea ice is sufficient to re-stabilize the shelves, which probably happens when continental albedo begins spiraling. That may still be a decade or two from now, but IMO we are quickly heading there.

So, good news: it isn't the methane that will kill everyone!
Bad news: the negative feedbacks that result from methane release are more than sufficient to get the job done, and occur well before any substantial % of methane is released, giving us even less time than in a clathrate-gun scenario.

Doom! 

Can you provide some links to these negative feedbacks you speak of? That will usher in an ice age....

[bbr2314]

I think one of the biggest arguments against large scale methane spikes is the absence of isotopic evidence in the ice cores. Why don't we see evidence of methane in the Eemian (where we are, temperature wise, roughly) or MIS 11 ?

sidd

I would think the answer to this is because when extant ice sheets are in existence, any rapid methane release triggers freshwater release / +warming / +H2O / higher albedo, which ends up resealing the beast before it can contribute any significant amount. I would think the same thing will happen with the current event, maybe it will be worse than normal, but we won't be around anyways because it isn't the 1% release of the area's methane that kills everything, it is rapid cooling due to the negative feedbacks associated with ^ which occurs as the release starts to get going in any substantial capacity (IMO). We have historical evidence for these very rapid drops in Greenland temperatures and coincidentally or not, 2018 has seen Greenland's coldest November temp on record (or was it October)?

In any case, the rapid warming due to methane release probably stops when sea ice is sufficient to re-stabilize the shelves, which probably happens when continental albedo begins spiraling. That may still be a decade or two from now, but IMO we are quickly heading there.

So, good news: it isn't the methane that will kill everyone!
Bad news: the negative feedbacks that result from methane release are more than sufficient to get the job done, and occur well before any substantial % of methane is released, giving us even less time than in a clathrate-gun scenario.

Doom! 

Can you provide some links to these negative feedbacks you speak of? That will usher in an ice age....

Hansen's papers have a good link, but besides those, I would argue that 2018 anomalies illustrate these negative feedbacks quite well. It is interesting that the huge + anomalies over Siberia and over the methane traps are still intact and worse than ever this year while Greenland has plunged back below normal alongside Canada. I think there is a good chance we see this worsen next year but I'll hold off until spring to make that prediction.

Here are the last six months of temp anomalies. I think the melting permafrost in Siberia is becoming a major component as to its ever-increasing + temperature departures. Perhaps the negative feedbacks need to become substantially worse before Siberia begins to cool again and the traps re-stabilize, and if that is the case, then things will only get warmer and warmer over Siberia / Laptev / etc until that occurs.

[Wherestheice]

I think one of the biggest arguments against large scale methane spikes is the absence of isotopic evidence in the ice cores. Why don't we see evidence of methane in the Eemian (where we are, temperature wise, roughly) or MIS 11 ?

sidd

I would think the answer to this is because when extant ice sheets are in existence, any rapid methane release triggers freshwater release / +warming / +H2O / higher albedo, which ends up resealing the beast before it can contribute any significant amount. I would think the same thing will happen with the current event, maybe it will be worse than normal, but we won't be around anyways because it isn't the 1% release of the area's methane that kills everything, it is rapid cooling due to the negative feedbacks associated with ^ which occurs as the release starts to get going in any substantial capacity (IMO). We have historical evidence for these very rapid drops in Greenland temperatures and coincidentally or not, 2018 has seen Greenland's coldest November temp on record (or was it October)?

In any case, the rapid warming due to methane release probably stops when sea ice is sufficient to re-stabilize the shelves, which probably happens when continental albedo begins spiraling. That may still be a decade or two from now, but IMO we are quickly heading there.

So, good news: it isn't the methane that will kill everyone!
Bad news: the negative feedbacks that result from methane release are more than sufficient to get the job done, and occur well before any substantial % of methane is released, giving us even less time than in a clathrate-gun scenario.

Doom! 

Can you provide some links to these negative feedbacks you speak of? That will usher in an ice age....

Hansen's papers have a good link, but besides those, I would argue that 2018 anomalies illustrate these negative feedbacks quite well. It is interesting that the huge + anomalies over Siberia and over the methane traps are still intact and worse than ever this year while Greenland has plunged back below normal alongside Canada. I think there is a good chance we see this worsen next year but I'll hold off until spring to make that prediction.

Here are the last six months of temp anomalies. I think the melting permafrost in Siberia is becoming a major component as to its ever-increasing + temperature departures. Perhaps the negative feedbacks need to become substantially worse before Siberia begins to cool again and the traps re-stabilize, and if that is the case, then things will only get warmer and warmer over Siberia / Laptev / etc until that occurs.

A. Can you share the link to the Hansen paper? B. The climate system is a bit more complex than the way you present it. Do you have data going back 10 years to support your claim?? Do you really think an ice age is happening? Because i haven’t seen any evidence to support that. I have to disagree. But I would like to see that Hansen paper.

All the best,

WTI

[wili]

As I understand it, the main path to methane breakdown involves the presence of OH. I'm not sure how much of that is in ice.

I also seem to have read that methane has a tendency to migrate through ice more than other, larger molecules, so a sharp peak in concentration is not really to be expected from ice core samples. If he were here still, I'm sure ASLR could come up with the relevant scientific articles, whether those supported my dim memory or set me straight. As it is, I'll have to ask others to see what they can come up with, as my mind is to tired for such a search tonight.

[Martin Gisser]

this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

If you want to reduce the problem to a mere technological one, we might indeed be at the end of the tether. "We can't solve problems by using the same kind of thinking we used when we created them." (Never trust an Einstein quote on the internet )

There are insultingly trivial solutions that don't require much technology. Just a change of mind and some concerted effort.

[Serrara Fluttershy]

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Which is why world leaders go through the motions, but put all their effort into maintaining BAU as long as possible.

If the world were going to end tomorrow, they would still want you to pay your bills and show up for work today.

The immediate threat is the day that stops happening.

Just wondering how much consensus there is on this, since accepting it as true changes everything. I gather that the catch is we have no idea when this will happen, or how quickly...

If this is true, then why are so many people on this forum talking about policy solutions, and how to get better politicians into office? Why are scientists publishing papers warning about climate thresholds, if there's no way to avoid a hothouse earth?

I find it all very disingenuous, and the result is that I don't want to trust anyone on anything, put my energy into advocating for anything, or really do anything other than to tell all humans to fuck off for being such pieces of shit.

I'm trying to find a relevant quote from Shakhova but not having luck atm (I think it may be video not print). Essentially, it comes down to methane releases from the gas hydrate stability zone having "exponential uncertainty" not linear uncertainty. e.g. we're not concerned about 100 vs 200 vs 300 MT of carbon released as methane, we're concerned with whether it's 100 MT or 1 GT or 10 GT etc.... This spread of uncertainty cannot currently be constrained with available methods and research, and it's hard to square away with IPCC's emission pathways when the uncertainty bounds are between "significant but manageable impacts to global mean surface temperature" and "dominating the overall warming fingerprint"

An earlier post on this thread disagrees with you...S&S say that clathrates are a red herring; the actual problem is subsea permafrost.

[Martin Gisser]

As I understand it, the main path to methane breakdown involves the presence of OH.

In the atmosphere it is. On the ground there are methane consuming microbes. Dunno how much help they are. Tim Lenton said many years ago that permafrost thaw isn't such a bomb because of methanotrophs. I have no idea about the latest research here.

This is from 2011: https://www.newscientist.com/article/dn21130-thawing-microbes-could-control-the-climate/

I'm not sure how much of that {OH} is in ice.

None. It is very reactive with a lifetime of ca. 1s and needs constant replenishment via UV light. (David Archer, The Global Carbon Cycle (2010) has a nice section on OH chemistry.)

Will forest fires increase OH?

[aperson]

And yes, wdmn, this is an Extinction Level Event over which we have NO influence.  It is beyond our technological capability to do anything about it.

Which is why world leaders go through the motions, but put all their effort into maintaining BAU as long as possible.

If the world were going to end tomorrow, they would still want you to pay your bills and show up for work today.

The immediate threat is the day that stops happening.

Just wondering how much consensus there is on this, since accepting it as true changes everything. I gather that the catch is we have no idea when this will happen, or how quickly...

If this is true, then why are so many people on this forum talking about policy solutions, and how to get better politicians into office? Why are scientists publishing papers warning about climate thresholds, if there's no way to avoid a hothouse earth?

I find it all very disingenuous, and the result is that I don't want to trust anyone on anything, put my energy into advocating for anything, or really do anything other than to tell all humans to fuck off for being such pieces of shit.

I'm trying to find a relevant quote from Shakhova but not having luck atm (I think it may be video not print). Essentially, it comes down to methane releases from the gas hydrate stability zone having "exponential uncertainty" not linear uncertainty. e.g. we're not concerned about 100 vs 200 vs 300 MT of carbon released as methane, we're concerned with whether it's 100 MT or 1 GT or 10 GT etc.... This spread of uncertainty cannot currently be constrained with available methods and research, and it's hard to square away with IPCC's emission pathways when the uncertainty bounds are between "significant but manageable impacts to global mean surface temperature" and "dominating the overall warming fingerprint"

An earlier post on this thread disagrees with you...S&S say that clathrates are a red herring; the actual problem is subsea permafrost.

I'm not talking about clathrates. I'm talking about the methane that is being capped by subsea permafrost that will naturally escape into the water column as permafrost degrades. S&S discuss the entire process from how CH4 migrates through taliks and weaknesses in permafrost up to the water column, then how it is mixed up the water column to the surface, and finally how it gets mixed into the atmosphere through upwelling created by low pressure systems. S&S argue that some regions of the Arctic ocean are more vulnerable to this process (like the East Siberian Arctic Shelf) and that the reserve of capped methane is large enough to vastly alter biogeochemical processes on the planet if even a small percentage is released.

There is of course exponential uncertainty in terms of the emissions pathway of the capped methane. Understanding the variance for emissions pathways requires understanding how permafrost degrades, how methane cycles in the water column, how it's upwelled from the surface into the atmosphere, and how methane cycles in the atmosphere.

See: https://doi.org/10.1029/2009JC005602

Arctic shallow hydrates, because of their inundation, have been exposed to temperatures about 5°C–10°C warmer than temperatures of terrestrial Arctic shallow hydrates for the past 5–10 kyr. On the basis of the heat transfer downward from relatively warmer ocean waters and upward from below, numerical models predict destabilization after ∼5–10 kyr of inundation [Romanovskii et al., 2005]. As a result, it is probable that large‐scale hydrate destabilization will occur first in the ESAS and other areas of submerged shallow permafrost. In fact, it is feasible that hydrate destabilization in the Arctic is currently creating free gas reservoirs trapped below the largely impermeable permafrost layer. In contrast to other areas of the Arctic Ocean, the ESAS water column provides a very short conduit for releasing CH4 to the atmosphere. This makes the ESAS a primary, important region for CH4 release, compared to other areas of the Arctic Ocean where the majority of CH4 passing through the water column is oxidized [Westbrook et al., 2009].

[53] Continued hydrate destabilization will lead to increasing pressure in these shallow reservoirs. In such case, fracturing and thawing of the permafrost will create pathways for deeper, hydrate‐derived CH4 deposits to escape to the sea surface, a process that we propose is currently occurring in the ESAS and is consistent with our data. Further, the shallowness of the ESAS implies hydrate‐derived CH4 here will affect atmospheric budgets much more than will most of the CH4 from deep‐sea hydrate deposits at lower latitudes [Kvenvolden, 1988, 2002].

[wdmn]

@Terry

Thank you Terry for your empathic reply.

[gerontocrat]

Re: methane

Archer treated the case of 200GT release, found it's roughtly equivalent to 750 ppm CO2, 5w/m^2

http://www.realclimate.org/index.php/archives/2012/01/an-online-model-of-methane-in-the-atmosphere/

sidd

I thought I would do a simple model of it all. I have used just 1 gigatonne of extra methane emissions each year. To put it in context I did find a figure of circa 0.6 gt per annum total methane emissions from all sources (2013).

Here are the assumptions:-
Simplified model of increased methane emissions effect as equivalent CO2 ppm                  
Assumptions:-                  
Methane degrades in the atmosphere to almost zero in 13   years
Methane degrades at the rate of    25%   of remaining balance, i.e. not linear      
Methane by weight greenhouse effect  is 25   times that of CO2      
                  
Business As Usual CO2 emissions are   40   gt per annum      
   Of which    50%   20gt remains in the atmosphere      
Business As Usual  CO2 emissions cause an annual 2.5   ppm increase in CO2 concentration

The results are attached.   A better profile of how methane degrades over time would help.

[Cid_Yama]

Links to papers posted earlier in this thread, to save you the time of looking for them.

https://forum.arctic-sea-ice.net/index.php/topic,12.msg130821.html#msg130821

https://forum.arctic-sea-ice.net/index.php/topic,12.msg126031.html#msg126031

https://forum.arctic-sea-ice.net/index.php/topic,12.msg131768.html#msg131768

https://forum.arctic-sea-ice.net/index.php/topic,12.msg132298.html#msg132298

Current rates and mechanisms of subsea permafrost degradation in the East Siberian Arctic Shelf, published 22 June 2017.

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

And here is a link to my methane archive so you can see how this progressed over the years to where we are now.  Being able to see where we were 2 years ago, 5 years ago, 10 years ago, provides an important perspective, allowing you to see just how fast and dramatically this has accelerated.

https://cid-yama.livejournal.com/tag/methane

[gerontocrat]

Links to papers posted earlier in this thread, to save you the time of looking for them.

Thanks Cid_Yama

One good turn deserves another.

https://www.eci.ox.ac.uk/research/energy/downloads/methaneuk/chapter02.pdf
Chapter 2: Climate science of methane

A good article for the enthusiastic amateur that explains a lot of how it all works (or does not).

Also confirms that methane does not degrade in a linear fashion (degrades fast then slow)

EDIT and here is Chapter 1
https://www.eci.ox.ac.uk/research/energy/downloads/methaneuk/chapter01.pdf

[Cid_Yama]

That book is pretty old.  They were talking about how the Kyoto Protocol will work which was signed in 1997, and textbooks notoriously use information much older than that.

We have come a long ways in methane research in the last quarter century, especially in the last decade.

Here is an excellent interactive chart showing atmospheric methane concentrations across time.

https://www.methanelevels.org/       

 

[Serrara Fluttershy]

Re: methane

Archer treated the case of 200GT release, found it's roughtly equivalent to 750 ppm CO2, 5w/m^2

http://www.realclimate.org/index.php/archives/2012/01/an-online-model-of-methane-in-the-atmosphere/

sidd

I thought I would do a simple model of it all. I have used just 1 gigatonne of extra methane emissions each year. To put it in context I did find a figure of circa 0.6 gt per annum total methane emissions from all sources (2013).

Here are the assumptions:-
Simplified model of increased methane emissions effect as equivalent CO2 ppm                  
Assumptions:-                  
Methane degrades in the atmosphere to almost zero in 13   years
Methane degrades at the rate of    25%   of remaining balance, i.e. not linear      
Methane by weight greenhouse effect  is 25   times that of CO2      
                  
Business As Usual CO2 emissions are   40   gt per annum      
   Of which    50%   20gt remains in the atmosphere      
Business As Usual  CO2 emissions cause an annual 2.5   ppm increase in CO2 concentration

The results are attached.   A better profile of how methane degrades over time would help.

Could you put this in simpler terms? The sheer amount of numbers is kinda overwhelming.

[Sleepy]

The Carbon Cycle: CO2 and Climate: Prof David Archer


Posted 20160608, 1,699 views now.

[gerontocrat]

That book is pretty old.  They were talking about how the Kyoto Protocol will work which was signed in 1997, and textbooks notoriously use information much older than that.

We have come a long ways in methane research in the last quarter century, especially in the last decade.

Here is an excellent interactive chart showing atmospheric methane concentrations across time.

https://www.methanelevels.org/       

Thanks for the chart. Yes, I am sure the science and the data collection systems and the modelling have all greatly improved since 1998 (the year that book uses for data).
BUT, the basics remain the same.

That book talks about how atmospheric methane in 1998 was 4,850 million tonnes, = 1,745 ppb (parts per billion). It also stated emissions are around 600 million tonnes per annum and decay in the atmosphere of around 575 million tonnes per annum giving a net increase per annum of just under 25 million tonnes.

Going forward to the levels in the graph at https://www.methanelevels.org/ and one finds that in the 20 years from 1998 to 2018 atmospheric methane increased by just under 300 million tonnes to 5,140 million tonnes, 1,850 ppb. i.e. an increase of 15 million tonnes per annum (a bit of a hiatus in early 2000's).  In the last 6 years the net increase per annum has gone up to about 21 million tonnes.

This would suggest one is still talking about small increases in emissions per annum from the 600 million tonnes in 1998. As yet my very over-simplified model still seems OK, as all I am trying to do is give a ballpark indication of the increase in the relentless rise in CO2e that would happen if, e.g. ESAS methane emissions, start to increase rapidly.

[gerontocrat]

Could you put this in simpler terms? The sheer amount of numbers is kinda overwhelming.

I will try.

There are vast deposits of carbon rich material in the Arctic, on land and under the sea. The question is, how many billion tonnes are we talking about? On Arctic land, estimated at 1,400 billion tonnes of carbon.Under the oceans, many times that.

Among most vulnerable of these deposits seems to be methane gas deposits trapped by a lid of permafrost in the shallow seas on the Russian side of the Arctic, especially the 2 million km2 of seas at least than 50 metres depth (mainly in the East Siberian Ice Shelf (ESAS). How much free methane is trapped there is not known - but it must be hundreds of billion of tonnes.

Methane emissions worldwide from all sources are quoted at 600 million tonnes per annum but my guess is a bit more than that. (As it is an old figure and atmospheric methane concentrations has increased since then).

So what effect would significant releases of methane have on global warming? Hence my simple model, which so far is still standing up.

The table attached has two examples.

Example #1. A small increase in year 1 of 100 million tonnes, growing by 10% per annum.

By year 15 the increased methane in the atmosphere is equivalent to increasing atmospheric CO2 by 4 parts per million, equivalent to 1.7 years "Business As Usual" CO2 annual increase.

But this is a release over 15 years of what must be far less than 1% of the free methane under the ESAS, let alone what is on land.

Example #2. An increase in year 1 of 1 billion tonnes, growing by 10% per annum.

By year 15 the increased methane in the atmosphere is equivalent to increasing atmospheric CO2 by 42 parts per million, equivalent to 17 years "Business As Usual" CO2 annual increase.

Put another way, the carbon budget often quoted as available to still avoid 2 degrees warming, disappears

But this is still a release over 15 years of what must be less than 10% of the free methane under the ESAS, let alone what is on land.

It is happening, but we do not know how quickly. And all we can do is wait - wait for the NASA data to tell us what is happening to methane in the atmosphere, because there is nothing, absolutely nothing, we can do about it.

[Cid_Yama]

Thanks, Terry.  I sometimes forget we aren't just a bunch of old men here discussing this, and I've never known how to soften the blow, I've always been very direct and to the point.

The recent IPCC report, even though usually a conservative toned down product due to political input, was still a death sentence for civilization, since it's remedies are know to be both politically and technologically impossible.  And they still avoided talking about the ESAS.
 

IPCC Admits End of the World as we know it

The United Nations Intergovernmental Panel on Climate Change has just come out with its latest report on the Earth’s ecosystemic health, and even in its gussied up findings — what many are calling “hopium” these days — it is, if read carefully, a prediction of the end of civilization.

According to the U.N. report, the only way to avoid this disaster would require “rapid and far-reaching” changes in the capitalist system that is the substructure of civilization, East and West. What must be changed, it says, are energy systems, land use, urban design, transportation, and building design — at a minimum. Changed so they contribute no greenhouse gases to the atmosphere — and can you imagine a world where transportation, for example, doesn’t pollute the air and we get along without cars, airplanes and cargo ships?

Though “energy systems” looks like a mild phrase, it actually implies the end of coal, gas and oil in the near future, the very fuels upon which industrial capitalism is based. There is no way that so-called “renewable” sources (which of course are not renewable because solar panels, windmills and batteries have finite lives and must be replaced) could ever replace those carbon-based fuels.

No wonder that most scientists — and anybody else who knows how politics works — say that this sort of wholesale economic change will not come about. There’s not a political system of any stripe anywhere in the world that is prepared to, or even knows how to, transform a society out of our modern way of life. That’s why one scientist has said in response to the U.N. report that it is nothing more than an academic exercise in “what would happen if a frog had wings.”

A decade ago, the “father of global warming”—the first scientist to sound the alarm on climate change in the 1980s to the US Congress—announced that we were too late: the planet had already hit the danger zone.

In a landmark paper, James Hansen, then head of NASA’s Goddard Institute for Space Studies, along with seven other leading climate scientists, described how a global average temperature above 1°Celsius (C)—involving a level of carbon dioxide (CO2) in the atmosphere of around 450 parts per million (ppm)—would lead to “practically irreversible ice sheet and species loss.” But, they added, new data showed that even 1°C was too hot.

At the time the paper was issued in 2008, atmospheric concentrations of CO2 were around 385 ppm. This is “already in the dangerous zone,” explained Hansen and his colleagues, noting that most climate models excluded self-reinforcing amplifying feedbacks which would be triggered at this level—things like “ice sheet disintegration, vegetation migration, and GHG [greenhouse gas] release from soils, tundra, or ocean sediments.”

Such feedbacks constitute tipping points which, once triggered, can lead to irreversible or even runaway climate change processes.

According to Hansen and his co-authors, these feedbacks “may begin to come into play on time scales as short as centuries or less.” The only viable solution to guarantee a safe climate, they wrote, is to reduce the level of greenhouse gases to around 350 ppm, if not lower.

Today, we are well in breach of the 1°C upper limit. And we have breached this limit at a much lower level of atmospheric CO2 than Hansen thought would be necessary to warm this much—as of May 2018, the monthly average atmospheric CO2 had reached 410ppm (the August measurement puts it at 409ppm.) This is the highest level of CO2 the earth has seen in 800,000 years.

The IPCC says that this would just be the beginning: we are currently on track to hit 3-4°C by end of century, which would lead to a largely unlivable planet.

They STILL haven’t dropped the other shoe. The “Special Report on Global Warming of 1.5C” contains terrifying forecasts about what will happen when we reach an average global temperature 1.5 degrees C higher than the pre-industrial average. (We are now at +1C.) But it still shies away from talking about the feedbacks, the refugees and mass death.

The report is a bracing dose of realism in many ways. It effectively says we can’t afford to go anywhere near +2C. It talks bluntly about the need to end all fossil fuel use, reforest vast tracts of marginal land, and cut down on meat-eating. It even admits that we will probably have to resort to geoengineering — “solar radiation management,” in the jargon.

So far, so good. At least it’s being honest about the problem — but only up to a point. “Not in front of the children” is still the rule for governments when it comes to talking about the mass movements of refugees and the civil and international wars that will erupt when the warming cuts into the food supply. And they still don’t want to talk openly about the feedbacks.

The governments take climate change very seriously these days, but they worry that too much frankness about the cost in lives of going past 1.5C will create irresistible pressure on them to take radical action now. In the ensuing struggle between the scientists and the politicians, the executive summary always gets toned down.

What got removed from the summary this time was any mention of “significant population displacement concentrated in the tropics” at +2C (i.e. mass migrations away from stricken regions, smashing up against borders elsewhere that are slammed shut against the refugees, the real reason for Trump's wall).

Even worse, “tipping points” are barely mentioned in the report. These are the dreaded feedbacks — loss of Arctic sea ice, melting of the permafrost, carbon dioxide and methane release from the oceans — that would trigger unstoppable, runaway warming.

They are called “feedbacks” because they are self-reinforcing processes that are unleashed by the warming we have already caused, and which we cannot shut off even if we end all of our own emissions.

If you don’t go into the feedbacks, then you can’t talk about runaway warming, and going to 4, 5 or 6 degrees C higher average global temperature, and hundreds of millions or billions of deaths. And if you don’t acknowledge that, then you will not treat this as the emergency it really is.

Just two years ago, amid global fanfare, the Paris climate accords were signed — initiating what seemed, for a brief moment, like the beginning of a planet-saving movement. But almost immediately, the international goal it established of limiting global warming to two degrees Celsius began to seem, to many of the world’s most vulnerable, dramatically inadequate; the Marshall Islands’ representative gave it a blunter name, calling two degrees of warming “genocide.”

The alarming new report you may have read about this week from the UN’s Intergovernmental Panel on Climate Change — which examines just how much better 1.5 degrees of warming would be than 2 — echoes the charge. “Amplifies” may be the better term. Hundreds of millions of lives are at stake, the report declares, should the world warm more than 1.5 degrees Celsius.

Nearly all coral reefs would die out, wildfires and heat waves would sweep across the planet annually, and the interplay between drought and flooding and temperature would mean that the world’s food supply would become dramatically less secure. Avoiding that scale of suffering, the report says, requires such a thorough transformation of the world’s economy, agriculture, and culture that “there is no documented historical precedent.”

If you are alarmed by those sentences, you should be — they are horrifying. But it is, actually, worse than that — considerably worse. That is because the new report’s worst-case scenario is, actually, a best case. In fact, it is a beyond-best-case scenario. What has been called a genocidal level of warming is already our inevitable future. The question is how much worse than that it will get.
 
Barring the arrival of dramatic new carbon-sucking technologies, which are so far from scalability at present that they are best described as fantasies of industrial absolution, it will not be possible to keep warming below two degrees Celsius — the level the new report describes as a climate catastrophe. As a planet, we are coursing along a trajectory that brings us north of four degrees. The IPCC is right that two degrees marks a world of climate catastrophe.

But the real meaning of the report is not “climate change is much worse than you think,” because anyone who knows the state of the research will find nothing surprising in it. The real meaning is, “you now have permission to freak out.”

At two degrees, the melting of ice sheets will pass a tipping point of collapse, flooding dozens of the world’s major cities.  Four hundred million more people will suffer from water scarcity, and even in the northern latitudes heat waves will kill thousands each summer. It will be worse in the planet’s equatorial band. In India, where many cities now numbering in the many millions would become unliveably hot, there would be 32 times as many extreme heat waves, each lasting five times as long and exposing, in total, 93 times more people. This is two degrees — practically speaking, our absolute best-case climate scenario.

At three degrees, southern Europe will be in permanent drought. The average drought in Central America would last 19 months and in the Caribbean 21 months. In northern Africa, the figure is 60 months — five years. The areas burned each year by wildfires would double in the Mediterranean and sextuple in the United States. Beyond the sea-level rise, which will already be swallowing cities from Miami Beach to Jakarta, damages just from river flooding will grow 30-fold in Bangladesh, 20-fold in India, and as much as 60-fold in the U.K. This is three degrees — better than we’d do if all the nations of the world honored their Paris commitments, which none of them are. Practically speaking, barring those dramatic tech deus ex machinas, this seems to me about as positive a realistic outcome as it is rational to expect.

Key dangers largely left out of the IPCC special report on 1.5C of warming are raising alarm among some scientists who fear we may have underestimated the impacts of humans on the Earth’s climate.

The IPCC report sets out the world’s current knowledge of the impacts of 1.5C of warming and clearly shows the dangers of breaching such a limit.

Tipping points merit only a few mentions in the IPCC report. Durwood Zaelke, founder of the Institute for Governance and Sustainable Development, said: “The IPCC report fails to focus on the weakest link in the climate chain: the self-reinforcing feedbacks which, if allowed to continue, will accelerate warming and risk cascading climate tipping points and runaway warming.”

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[Cid_Yama]

New science suggests methane packs more warming power than previously thought

It’s long been known that methane is a major contributor to global warming, responsible for roughly a quarter of the warming we’re experiencing today and second only to carbon dioxide in its impact on the current climate.

But research suggests methane has an even more potent warming effect on the climate than scientists previously thought.

For example, a study in Geophysical Research Letters significantly revises estimates of the energy trapped by methane by including its previously-neglected absorption of near-infrared radiation (past research included only infrared absorption—a different part of the radiation spectrum).

Packing a bigger punch

The study finds that the radiative efficiency—how much energy is trapped in the climate system by unit mass of methane—is 23% higher than estimates used in the 2013 Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5).

Methane also impacts warming indirectly by creating more tropospheric ozone and stratospheric water vapor. Its global warming potential (GWP) accounts for both its direct and indirect warming effects. But the new research affects only the direct radiative properties. The net increase in methane’s GWP is 14% compared to their IPCC AR5 values (over both 20- and 100-year time horizons).

Implications for IPCC, science, and policy

What does the research mean for the generally accepted estimates used in the science to guide policymakers? The IPCC is generally regarded as having a relatively conservative outlook on evolving science, as its content needs to be agreed upon by hundreds of representatives from across the world. Further, it inherently lags the best and most current science because any research published after the writing deadlines cannot be included.

However, it is very likely that these findings will be included in the IPCC Sixth Assessment Report, due in 2021, considering that some of the authors were also authors of the IPCC AR5.

In the meantime, scientific assessments of methane emissions should use the updated estimates of methane’s ability to trap heat (14% higher than the current IPCC estimate).

link

Radiative forcing of carbon dioxide, methane, and nitrous oxide: A significant revision of the methane radiative forcing

[gerontocrat]

New science suggests methane packs more warming power than previously thought

In the meantime, scientific assessments of methane emissions should use the updated estimates of methane’s ability to trap heat (14% higher than the current IPCC estimate).

Thanks, Cid_Yama, I think
Excuse me while I try to raid your brain.

Qu1.
One day might we get a study that says the abyss over which we are teetering is shallower, not deeper ?

Qu2.
When amateurs like me do back of envelope calculations it helps to have a number to use.

E.g. the Greenhouse effect of CH4 c.f. CO2. When one looks around the various sources one finds multipliers of 25, 28, and 30 (for the troposphere) and 75 to 125 (for the stratosphere). I assume the troposphere is less significant?

Now we have a study that says CH4's GWP is 25% above the value used by the IPCC, and merely 0.5% for CO2's, and then an article that says add 14%.

If one is doing a simple spreadsheet just looking at the impact over the next few years of an increase in CH4 emissions measured in terms of increases in CO2 ppm, what multiplier do you think would be the least unreasonable?

Qu3. Has the so-called carbon budget just taken a significant hit?

[wdmn]

Oh no! Not the GWP of methane question again! 

[gerontocrat]

Oh no! Not the GWP of methane question again! 

Yes, because the study referred to above says it is underestimated by 25%

[wdmn]

Oh no! Not the GWP of methane question again! 

Yes, because the study referred to above says it is underestimated by 25%

Bad joke. Definitely a worthwhile discussion; like most of those it will be messy.

[TerryM]

Cid
I tried to raise some interest on the IPPC thread by linking to an earlier post of your's, but got no feedback.


About the same time as Neven opened this Forum there had been quite a discussion at his Blog re. S&S's research. The pictures they drew were horrific, and while I don't remember the facts and figures they arrived at, I do recall being totally convinced that they were correct and that we had little time left.


Worrying about whether the Evil Russians had stolen St. Hillary's election seems like a distraction when the real questions are. "Can my grandson expect to turn on the radio?, drive a car?, read after dark?, or vote in an election."


Should he study political science or flint knapping?
Terry

[Cid_Yama]

You don't have to live a long life to live a full one.  Focus on quality not quantity.

It is already happening.  The enhanced wildfires, the enhanced tropical storms, enhanced heat waves, crop failures, increasing water scarcity, climate refugees, insect migrations, ice losses at the poles, etc.

People are dying now by the thousands, just not in the western world just yet.  But global crop failures, inducing pandemics due to weakened immune systems, and wars, is just around the corner.  And diseases travel by airliner.

And this will not be linear.  Thus, linear progressions will be worthless.

As I said, this is an Extinction Level Event, and it is happening now.  No one is coming out the other end.  The planet will become uninhabitable for warm-blooded creatures, and what will come after that will rival the Permian mass extinction.

Live the best you know how, for however long you have.  If you won't reach retirement age within the next ten years, don't count on it.  You might want to put that money to better use.  Even 10 years seems optimistic.  The acceleration over the last 5 years doesn't bode well.  I expect major global crop failures within 2 years.

Massive emissions of methane in the Arctic become a significant source of greenhouse gases, a study reveals

The rate of vertical degradation of subsea permafrost in the East Siberian Arctic Shelf (ESAS) is 18 cm a year over the past 30 years, which is greater than previously thought. Scientists from Tomsk Polytechnic University received this data after the comprehensive study of subsea permafrost not only in the Russian Arctic but also in the Arctic as a whole.

TPU scientists and co-authors from Russia and Sweden have recently published findings of the study in Nature Communications.

Basing on the repeated drilling of four wells performed by the Institute of Permafrost Siberian Branch of Russian Academy of Sciences in 1982-1983, scientists have proved that the rates of vertical degradation of subsea permafrost amount to18 cm a year over the last 30 years (the average is 14 cm a year) which is greater than it was assumed before.

'New data obtained by complex biochemical, geophysical and geological studies conducted in 2011-2016 resulted in the conclusion that in some areas of the East Siberian Arctic Shelf the roof of the subsea permafrost had already reached the depth of hydrates' stability the destruction of which may cause massive releases of bubble methane.

According to our findings published earlier in Nature Geoscience, Science and Philosophical Transactions, Royal Society, the size of CH4 bubble flaw from the bottom sediments into the ESAS water can vary from milligrams to tens or hundreds of grams per square meter a day depending on the state of subsea permafrost, which leads to the concentration increase of atmospheric CH4 in the surface layer to values 2-4 times exceeding background concentrations measured in our planet,' says the first author of the paper Professor Natalia Shakhova, the TPU Department of Geology and Minerals Prospecting.

She notes that these findings were confirmed during the expedition to the East Siberian Arctic Self in 2016. The expedition was organized and conducted jointly with the scientists from the Pacific Oceanological Institute FEB RAS, with the participation of the Institute of Oceanology RAS and the Institute of Atmospheric Physics RAS. More data will be published in 2018.

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Current rates and mechanisms of subsea permafrost degradation in the East Siberian Arctic Shelf

It was shown that slight changes in seafloor erosion and sedimentation patterns that change the thermal and pressure regime below the seafloor could be viable mechanisms for unroofing underlying gas reservoirs, which can release CH4 in large quantities66. Once initiated, erosion could propagate further downward and migrate laterally to adjacent areas, driven by venting gas. Erosion of a few tens of seafloor metres could unroof over-pressured shallow gas reservoirs and buoyant hydrate-laden sediment accumulations beneath the seafloor, triggering rapid gas release66,67.

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[Cid_Yama]

From June 2017:

Subsea permafrost on East Siberian Arctic Shelf in accelerated decline

Dr. Shakhova: As we showed in our articles, in the ESAS, in some places, subsea permafrost is reaching the thaw point. In other areas it could have reached this point already. And what can happen then? The most important consequence could be in terms of growing methane emissions… a linear trend becomes exponential.

This edge between it being linear and becoming exponential is very fine and lays between frozen and thawed states of subsea permafrost. This is what we call the turning point. To me, I cannot take the responsibility in saying there is a right point between the linear and exponential yet, but following the logic of our investigation and all the evidence that we accumulated so far, it makes me think that we are very near this point. And in this particular point, each year matters.

Gas in the areas of hotspots is releasing from the seabed deposits, in which free gas has accumulated for hundreds of thousands, or even for a million years. This is why the amount of this gas and its power in releasing (due to its high pressure) is tremendous.

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.

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 disintegration of subsea permafrost and associated destabilisation of seabed deposits whether it is hydrates or free gas accumulations.

There is no mechanism to stop permafrost disintegration in the ESAS besides shelf exposure above the sea level that would serve to freeze the gas migration paths so that they integrate with the permafrost. Before that, the amount of methane that is releasing will increase while the supply lasts.

As gas within the sedimentary basins of the ESAS have been accumulating for a million years with no way to be released earlier, the supply for currently occurring emissions is tremendous. Because the shelf area is very shallow (mean depth is less than 50 metres), a fraction of these emissions will reach the atmosphere. The problem is that this fraction would be enough to alter the climate on our planet drastically.

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[Serrara Fluttershy]

Cid
I tried to raise some interest on the IPPC thread by linking to an earlier post of your's, but got no feedback.


About the same time as Neven opened this Forum there had been quite a discussion at his Blog re. S&S's research. The pictures they drew were horrific, and while I don't remember the facts and figures they arrived at, I do recall being totally convinced that they were correct and that we had little time left.


Worrying about whether the Evil Russians had stolen St. Hillary's election seems like a distraction when the real questions are. "Can my grandson expect to turn on the radio?, drive a car?, read after dark?, or vote in an election."


Should he study political science or flint knapping?
Terry

Has the current situation changed in any way?