From up north, we have some more troubling news. Actually very troubling. Catastophic release of methane hydrates is a prime suspect in a few events dramatic enough to show in the earth's geological records, coarse and obscured as that record may be. (Our actions today will be featured prominently in that record for anyone looking back a million years from now.) It has been a worry for many years that humanity is running the risk of triggering such a release again, which would truly pile disaster on top of calamity.
New research coming out in Science today indicates that this most dire of feedbacks may well be underway already. Below is the text of a press release I received about it last night.
Fairbanks, Alaska--A section of the Arctic Ocean seafloor that holds vast stores of frozen methane is showing signs of instability and widespread venting of the powerful greenhouse gas, according to the findings of an international research team led by University of Alaska Fairbanks scientists Natalia Shakhova and Igor Semiletov.The research results, published in the March 5 edition of the journal Science, show that the permafrost under the East Siberian Arctic Shelf, long thought to be an impermeable barrier sealing in methane, is perforated and is leaking large amounts of methane into the atmosphere. Release of even a fraction of the methane stored in the shelf could trigger abrupt climate warming.
"The amount of methane currently coming out of the East Siberian Arctic Shelf is comparable to the amount coming out of the entire world's oceans," said Shakhova, a researcher at UAF's International Arctic Research Center. "Subsea permafrost is losing its ability to be an impermeable cap."
Methane is a greenhouse gas more than 30 times more potent than carbon dioxide. It is released from previously frozen soils in two ways. When the organic material--which contains carbon--stored in permafrost thaws, it begins to decompose and, under oxygen-free conditions, gradually release methane. Methane can also be stored in the seabed as methane gas or methane hydrates and then released as subsea permafrost thaws. These releases can be larger and more abrupt than those that result from decomposition.
The East Siberian Arctic Shelf is a methane-rich area that encompasses more than 2 million square kilometers of seafloor in the Arctic Ocean. It is more than three times as large as the nearby Siberian wetlands, which have been considered the primary Northern Hemisphere source of atmospheric methane. Shakhova's research results show that the East Siberian Arctic Shelf is already a significant methane source: 7 teragrams yearly, which is equal to the amount of methane emitted from the rest of the ocean. A teragram is equal to about 1.1 million tons.
"Our concern is that the subsea permafrost has been showing signs of destabilization already," she said. "If it further destabilizes, the methane emissions may not be teragrams, it would be significantly larger."
Shakhova notes that Earth's geological record indicates that atmospheric methane concentrations have varied between about .3 to .4 parts per million during cold periods to .6 to .7 parts per million during warm periods. Current average methane concentrations in the Arctic average about 1.85 parts per million, the highest in 400,000 years, she said. Concentrations above the East Siberian Arctic Shelf are even higher.
The East Siberian Arctic Shelf is a relative frontier in methane studies. The shelf is shallow, 50 meters or less in depth, which means it has been alternately submerged or terrestrial, depending on sea levels throughout Earth's history. During Earth's coldest periods, it is a frozen arctic coastal plain, and does not release methane. As the planet warms and sea levels rise, it is inundated with seawater, which is 12-15 degrees warmer than the average air temperature.
"It was thought that seawater kept the East Siberian Arctic Shelf permafrost frozen," Shakhova said. "Nobody considered this huge area."
Earlier studies in Siberia focused on methane escaping from thawing terrestrial permafrost. Semiletov's work during the 1990s showed, among other things, that the amount of methane being emitted from terrestrial sources decreased at higher latitudes. But those studies stopped at the coast. Starting in the fall of 2003, Shakhova, Semiletov and the rest of their team took the studies offshore. From 2003 through 2008, they took annual research cruises throughout the shelf and sampled seawater at various depths and the air 10 meters above the ocean. In September 2006, they flew a helicopter over the same area, taking air samples at up to 2,000 meters in the atmosphere. In April 2007, they conducted a winter expedition on the sea ice.
They found that more than 80 percent of the deep water and greater than half of surface water had methane levels more than eight times that of normal seawater. In some areas, the saturation levels reached at least 250 times that of background levels in the summer and 1,400 times higher in the winter.
They found corresponding results in the air directly above the ocean surface. Methane levels were elevated overall and the seascape was dotted with more than 100 hotspots. This, combined with winter expedition results that found methane gas trapped under and in the sea ice, showed the team that the methane was not only being dissolved in the water, it was bubbling out into the atmosphere.
These findings were further confirmed when Shakhova and her colleagues sampled methane levels at higher elevations. Methane levels throughout the Arctic are usually 8 to 10 percent higher than the global baseline. When they flew over the shelf, they found methane at levels another 5 to 10 percent higher than the already elevated arctic levels.
The East Siberian Arctic Shelf, in addition to holding large stores of frozen methane, is more of a concern because it is so shallow. In deep water, methane gas oxidizes into carbon dioxide before it reaches the surface. In the shallows of the East Siberian Arctic Shelf, methane simply doesn't have enough time to oxidize, which means more of it escapes into the atmosphere. That, combined with the sheer amount of methane in the region, could add a previously uncalculated variable to climate models.
"The release to the atmosphere of only one percent of the methane assumed to be stored in shallow hydrate deposits might alter the current atmospheric burden of methane up to 3 to 4 times," Shakhova said. "The climatic consequences of this are hard to predict."
Shakhova, Semiletov and collaborators from 12 institutions in five countries plan to continue their studies in the region, tracking the source of the methane emissions and drilling into the seafloor in an effort to estimate how much methane is stored there.Shakhova and Semiletov hold joint appointments with the Pacific Oceanological Institute, part of the Far Eastern Branch of the Russian Academy of Sciences. Their collaborators on this paper include Anatoly Salyuk, Vladimir Joussupov and Denis Kosmach, all of the Pacific Oceanological Institute, and Orjan Gustafsson of Stockholm University.
Physical Science
Environment
Comments
Is there a graph of atmospheric methane concentration over time? I realize CH4 isn't as well mixed as CO2, but as long as the methodology is consistent and described, it would really help understand whether the current arctic releases are "normal" or not.
Posted by: GFW | March 5, 2010 10:21 AM
Methane has been rising recently even though for a number of years levels were stable.
http://climateprogress.org/2009/04/25/noaa-methane-levels-2008/
The stabilization of methane must have had some effect on temperature trends, BTW. This is seldom considered.
Posted by: Joseph | March 5, 2010 2:52 PM
Do you know how / whether this information changes / will change the current climate model predictions? Is this really big news, or is it a rather sensationalist press release?
Posted by: canbanjo | March 5, 2010 3:02 PM
This had to happen.
Natural sequestration of methane would necessarily include a portion of stores held near long-term equilibrium. Nature does not employ 'margining' of structural & material properties as Engineers would. If it could freeze at 10milliKelvin below long-term equilibrium, it did.
Long-term equilibrium is being re-established, including the activation of feedback mechanisms. Too bad for superstitious humans and their meager cohort of rationalists: it's positive feedback.
Posted by: Hey! Get This . . . | March 5, 2010 3:26 PM
We have no idea where all the methane released to the atmosphere comes from. Methane oxidizes fairly quickly, within 10 years, to CO2. Doubling methane from current values of 1.8 ppm would be the equivalent of adding 60 ppm CO2 (about 0.2 deg C w/o feedbacks (which can be positive AND negative). There has been relatively little increase in atmospheric methane over 15 years. Methane started increasing in 1750 which was near the end of the Little Ice Age.
Methane bubbles out of the surface in many locations. Before we started using oil and gas for energy, oil and gas just seeped out of the land. There is still quite a bit of seepage in the oceans, but we have no idea how much since it's hard to measure.
For all we know, this seepage in this small area of the Arctic (relative to global surface area) has been going on off and on for the past 10,000 -20,000 years, since the end of the last ice age. We have had warmer periods in the Arctic, including the 1930's , MWP, etc. but it's not clear this seepage is even due to warming.
And what does this mean anyways ""It was thought that seawater kept the East Siberian Arctic Shelf permafrost frozen," Shakhova said. "Nobody considered this huge area."
What keeps the permafrost/methane frozen is low temperatures below freezing and/or high pressure which causes methane to form hydrates even at warmer temperatures (up to 18 deg C). However, 40-50 meters is not enough pressure for methane to form hydrates at warmer temperatures. Permafrost and hydrated sediment does have a low thermal conductivity so it probably takes a long time for any warming to penetrate. If there are hydrates, and hydrates are melting, the reaction is endothermic, so this will help slow any warming as well. However, since the end of the last ice age, we know land that was previously under glaciers has been rising since it is free from the weight of the glaciers, this would have the effect of reducing the depth (and pressure) on any hydrates formed long ago.
Any methane being released at such shallow areas may very well be seepage (nothing in the article rules this out). It is not like there is not a lot of oil and gas in the Arctic. Russia has no clear idea as to the reserve potential of East Siberia as it has been relatively unexplored, but since the Western Siberian fields are being depleted they will be looking East.
Posted by: pft | March 6, 2010 12:23 AM
It actually started to increase abruptly in the 1790s, when the industrial revolution broke. I don't have a graph of it online, but I have a graph of CO2 (here) that is similar. Imagine it like that, but add a slight upward slope.
It's incomprehensible to me that people can look at the exponential rise in methane in CO2 that occurred during the industrial era, and still deny we are responsible for that rise.
Posted by: Joseph | March 6, 2010 6:47 AM
Real Climate has this post in response to the press buzz, putting the paper in perspective.
Posted by: dhogaza | March 6, 2010 10:41 AM
This news doesn't bode well.
It would have been nice not to put humanity through a mass extinction event in the 21st century, but we lost that opportunity already. It's all damage control now, baby.
The only question left is how bad are we going to let it get before we a. admit that it's happening, and b. decide to co-operate globally to do something to mitigate potentially catastrophic consequences.
This will be the 21st century equivalent of WWII in terms of the impact it has on global humanity, and just as in WWII, horrors resulting in hundreds of millions (possibly billions) of deaths and unprecented environmental effects will leave a lasting imprint on civilization's psyche.
Just as in WWII, we will be forced to recognize the ways in which we kill ourselves, and be forced, eventually, to grapple with the new level of responsibility it brings us.
God didn't cause this and God won't fix it. We're in the driver's seat, drunk on oil and thrilled by our speed.
The hangover is going to be a bitch.
Posted by: yogi-one | March 6, 2010 2:55 PM
Coby,
maybe you could put in an update with the link that dhogaza has provided. If RealClimate.org is the authority on these matters, then I think you ought to try to include the analysis of why they think this isn't a big deal.
Posted by: maxwell | March 7, 2010 6:07 AM
That was interesting. Thanks, Dho.
Posted by: skip | March 7, 2010 9:38 AM
What RealClimate.org are arguing is that this is like -- to use a different analogy to the one they used -- having cancer and then getting AIDS on top of that.
Posted by: Joseph | March 7, 2010 11:23 AM
James,
from the RealClimate.org post
'Is now the time to get frightened?
No.'
and
'Methane sells newspapers, but it’s not the big story...'
and, most importantly,
'What’s missing from these studies themselves is evidence that the Siberian shelf degassing is new, a climate feedback, rather than simply nature-as-usual, driven by the retreat of submerged permafrost left over from the last ice age.'
I think the analogy of cancer on top of AIDS has to do with a catastrophic methane, which they seem to believe is not what is happening in the situation in this paper. In fact, David clearly states,
'The Siberian Margin might rival the whole rest of the world ocean as a methane source, but the ocean source overall is much smaller than the land source...The ocean is small potatoes, and there is enough uncertainty in the methane budget to accommodate adjustments in the sources without too much overturning of apple carts.'
It's important to focus on the heart of the argument rather than taking the most extreme portions of it. David is clearly making the argument that this paper is not evidence for some catastrophic event that is unfolding before us. Using your analogy, we still just have AIDS.
Posted by: maxwell | March 7, 2010 2:27 PM
I could not figure out from the Press Release whether it was thought this was a new process or if it has been occurring all the/for some time.
Surely that must be established before we start worrying too much about this?
Posted by: Jack Savage | March 7, 2010 11:55 PM
maxwell
I absolutely LOVE the selectivity and sheer hypocrisy of the deniliast movement when it comes to constructing an argument. Firstly, to attempt to appeal to RealClimate (post #9) as the experts on an issue, because you think they support your denialist position, is absolutely priceless, because we all know RealClimate is well known for debunking denialist propoganda, and to accept them as the 'experts' on a climate change is strange in the extreme. Please tell me that you accept them as the experts on all things to do with climate change, and not just when it appears that they support your position? Are you going to quote them on every issue?
And I am totally confused about when and where it is appropriate to 'appeal to authority'. In post #9, you appear to be appealing to the authority of RealClimate to support your view, as follows:
"....maybe you could put in an update with the link that dhogaza has provided. If RealClimate.org is the authority on these matters, then I think you ought to try to include the analysis of why they think this isn't a big deal...."
However, in post # 46 of 'A chilling effect on a warming theory', you state:
".... The point is that making an argument pandering to the fact that 'experts' said such and such, therefore it must be true is first rate example of how not to make an argument. It is known as argument from authority or argumentum ad verecundiam. Don't you love Latin?..."
So I am confused. Should I appeal to authority - or as you say in Latin argumentum ad verecundiam (argument to respect) - to support my argument, or should I only do that when the authority says something that supports my own world view?
Posted by: mandas | March 8, 2010 12:35 AM
maxwell
Oh - and just a little tip. Try to remember who's blog you are posting on. 'James' is over at "The Island of Doubt". Our host here is coby. It's a bit like calling out the wrong woman's name when you are cumming. Never a good thing.
Posted by: mandas | March 8, 2010 12:46 AM
I am not sure Maxwell is the only one tying himself in knots. Realclimate has become a bit of a propaganda machine itself lately,spending far too much time debunking the tiny minority of "deniers" or whatever you like to call them.
It is supposed to be a reliable source of carefully researched climate science and as such can surely be drawn upon by any side of the argument as an appeal to the science rather than an appeal to authority.
I do not see any difficulty with Maxwell agreeing with Realclimate on the issue and Mandas disagreeing (if indeed he does, he has not said!) . Mandas should no more taunt Maxwell now to agree with everything on Realclimate than if Maxwell should now taunt Mandas now to disagree with everything on Realclimate. It really does not move a debate forward.
Posted by: Jack Savage | March 8, 2010 1:15 AM
'mandas' is neither agreeing or disagreeing with what is said over at RealCimate. But he (I) do have an issue with people selectively quoting from them and holding them up as 'experts' on one issue, when they patently disagree with them on just about everything else. And I do have an issue with people appealing to authority when it suits them, but castigating others for similar appeals to authority.
I don't like hypocrites - pure and simple.
Posted by: mandas | March 8, 2010 1:29 AM
'deniers" or whatever you like to call them" - J Savage
Deniosaurs.
Posted by: Dappledwater | March 8, 2010 1:52 AM
RealClimate are being correctly cautious especially about whether this is anything new or not. So I guess it is apparent that all the accusations of "alarmists" were misguided after all.
However, I find maxwell's quote pretty ironic to say the least! He quoted RC:
"Is now the time to get frightened? No." Okay, but why no? They go on: "Imagine you are in a Toyota on the highway at 60 miles per hour approaching stopped traffic, and you find that the brake pedal is broken. This is CO2. Then you figure out that the accelerator has also jammed, so that by the time you hit the truck in front of you, you will be going 90 miles per hour instead of 60. This is methane. Is now the time to get worried? No, you should already have been worried by the broken brake pedal."
Seems to have just a little bit different message than maxwell would have us believe.
Posted by: coby | March 8, 2010 3:30 AM
I think, in Max's defense, he simply meant the article denies that we have to worry about methane in especially.
Posted by: skip | March 8, 2010 7:43 AM
mandas, I confused Joseph with James. Sorry about that.
As for hypocrites, I am merely pointing out to Coby that if RealClimate can be cited in the meat and potatoes of this post about the concerns over methane as a greenhouse gas, then they should be properly cited explaining why the nature of THIS PARTICULAR ARTICLE is not a sufficient reason to get all up in arms. I'm holding him to his standard. Since I have never mentioned anything disparaging about the science the RealClimate brings to the table, I really don't know what you're talking about when it comes to my hypocrisy.
If you have a problem with the citations I provide, then I think you'd better provide better citations of the OVERALL ARGUMENT THAT PARTICULAR POST ON REALCLIMATE IS TRYING TO MAKE! Merely pointing and yelling is not really an argument. Calling me names is not really an argument. Pointing out that I confused two people's names is not an argument. If you think that post on RealClimate is making another argument, please cite it.
Coby, the same goes for you.
It is obvious even to a child that David, in that quote, is discussing the prospects of methane released on a catastrophic scale. This is because methane only lasts in the atmosphere about a decade, as David also points out, while CO2 has a longer lifetime. But in relation to the rest of the methane release on the planet, the vent featured IN THIS ARTICLE is 'small potatoes'.
No amount of taking quotes out of context can dispute that this is the conclusion of that particular RealClimate piece.
But that's quite an argument you guys are making. Because I mix up names, hold people to their standards and actually know how to make an cogent argument means that I must be wrong. You're really making progress.
Posted by: maxwell | March 8, 2010 11:54 AM
maxwell
Thanks for validating my views regarding your hypocrisy (and I was making that point about your double standards when it comes to appeals to authority, not about your citations). You point out to me that 'calling you names is not really an argument', then you go ahead say this about coby:
"...Coby, the same goes for you. It is obvious even to a child..."
So I guess it is ok to call someone names if you are doing it, but not ok if someone does it to you. I'm pretty certain that fits the definition of hypocrisy pretty well.
Posted by: mandas | March 8, 2010 2:03 PM
There is evidence to show the current degassing is a recent occurance, starting in 2003
From ‘The Independant’,
“The preliminary findings of the International Siberian Shelf Study 2008, being prepared for publication by the American Geophysical Union, are being overseen by Igor Semiletov of the Far-Eastern branch of the Russian Academy of Sciences. Since 1994, he has led about 10 expeditions in the Laptev Sea but during the 1990s he did not detect any elevated levels of methane. However, since 2003 he reported a rising number of methane “hotspots”, which have now been confirmed using more sensitive instruments on board the Jacob Smirnitskyi.”
Posted by: jcrabb | March 8, 2010 2:42 PM
I've produced a graph of the methane concentration from 1008 to 1993, based on the Law Dome reconstruction made available by Etheridge et al. (1998). Feel free to use.
I don't doubt David over at RealClimate.org is right that methane does not stay in the atmosphere as long as CO2, but it's clear that some of it stays.
There is a mechanism to increase the methane concentration in the atmosphere: Human civilization.
Posted by: Joseph | March 8, 2010 2:56 PM
The ESAS contains an estimated 540 billion tonnes of Methane, as it has started venting due to 'melting' of it's permafrost lid, it seems reasonable to expect it to continue venting, barring refreezing, releasing billions of tonnes of Methane. Seems reasonable to expect that as warming continues, the rate of venting will increase.
Even though Methane has a short lifespan in the atmosphere, it still degrades into CO2, so either way the result is a significant increase in GHG's, hence I don't quite understand the nonchalance towards this new, massive source of GHG's that we have no control over. To me this seems more like a tipping point, permafrost collapse was not expected for some time yet, and it was posed as a tipping point.
Posted by: jcrabb | March 8, 2010 4:45 PM
Joseph, you might want to change the left axis to ppb.
Posted by: Juice | March 9, 2010 1:07 AM
@Juice: Good catch. I've fixed it.
Posted by: Joseph | March 9, 2010 4:44 AM
Joeseph,
how does your reconstruction take the 'divergence problem' into account?
Posted by: maxwell | March 9, 2010 5:44 AM
Are you referring to the tree-ring divergence problem, maxwell? That's for temperature reconstructions. The Etheridge et al. (1998) methane reconstruction is from gas trapped in ice-cores, obtained at the Law Dome.
There's also instrumental data for methane, but it doesn't go back too far, of course.
Posted by: Joseph | March 9, 2010 6:04 AM
Joeseph,
I saw there was a reference to ice cores in the link you had on your first comment on the reconstruction. There was also a mention of 'firn air' and other air born measurements, but I'm not sure what they mean.
I was more interested in a general divergence in correlation between these other proxies and observational data for the reconstruction you've provided.
Cheers.
Posted by: maxwell | March 9, 2010 6:55 AM
Joseph's graph may be a "reconstruction", but it's definitely not a proxy reconstruction. The modern instrumental measurements are of actual methane in the air. The ice core measurements are of methane trapped in air bubbles in the ice. Ice core dates are solid. I would have to read the original papers to see what steps they take to avoid contamination, but ice cores from multiple locations agree on the pre-industrial value and the timing of the increase. Finally, the ice core data matches the direct instrumental data in the period of overlap. The only thing to add is that between the end of Joseph's graph (1993) and present, the methane concentration has risen to about 1785 ppb.
(A proxy reconstruction measures one thing as a proxy for another (like tree ring widths for temperature or other factor that limits tree growth).)
Posted by: GFW | March 9, 2010 7:24 AM
GFW, thanks for the update. I will quibble slightly, however, over the language.
Ice cores measurements are proxies for the amount of any gas in the atmosphere at the time of freezing. One is able to measure the actually gas concentrations in such cores, but the question remains of whether this is actually a measurement of the past atmosphere. It seems this is true for ice core measurements, but this fact does not mean they are not proxies.
Posted by: maxwell | March 9, 2010 8:52 AM
As atmospheric Methane has not changed significantly over the last thousand years, prior to the current period, isn't it fair to say that current temps. are unprecedented. If there were comparable temps. then similar substantial increase of Methane emissions from Wetlands etc, that are currently occuring, should be seen around the MWP, whenever that was.
Posted by: jcrabb | March 9, 2010 5:24 PM
jcrabb, your conclusion seems to contradict Joeseph's. If humans are responsible for the rise in methane we are seeing currently, then that could account for it and past warm periods may or may not have had similar amounts of methane to today. There would be no way to make a correlation because we know that the warmth is not causing it now.
That said, I will again point out that the venting this article describes is a very small component to the overall methane budget and even if such things are common during warmer periods, they may not affect past readings for atmospheric concentrations very much at all.
Posted by: maxwell | March 9, 2010 5:38 PM
maxwell, around 50% of the current atmospheric Methane level is due to warm wetlands emitting more Methane.
So higher temps are proven to raise Atmospheric Methane levels.
As there is no natural Methane sequestration process, then increased Methane emissions due to increased temps. should show up in the historical record.
Posted by: jcrabb | March 9, 2010 6:04 PM
jcrabb, do you have a source for your number? This site says that a quarter of methane comes from wetlands.
http://www.ghgonline.org/methanewetland.htm
That seems like an awfully hard thing to measure, however.
And there is a natural sequestration mechanism. It's called oxidation chemistry.
From Wikipedia's entry on methane,
'Methane is a relatively potent greenhouse gas with a high global warming potential of 72 (averaged over 20 years) or 25 (averaged over 100 years).[2] Methane in the atmosphere is eventually oxidized, producing carbon dioxide and water. As a result, methane in the atmosphere has a half life of seven years.'
If reconstructions do not have sufficient time resolution of time scales smaller than 100 years, then whatever rises in concentrations that have occurred could be completely missed.
Joeseph, do you know how the ice core data deals with this fact? It looks like the x-axis has units of 30 years or just over 4 half-lives. Is that correct? If it is, almost 95% of methane released just after one time point would have oxidized by the next time point.
Posted by: maxwell | March 9, 2010 6:21 PM