I haven't had a chance to read the original paper - I'm getting ready to head out of town and probably won't get to it until next week, but I just got a press release from U Alaska Fairbanks about a recent paper in this month's issue of Science that suggests that we've got bigger methane problems than we knew about.
From the UAK press release:
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."
And
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.
From the New York Times today:
Natalia Shakhova, a scientist at the university and a leader of the study, said it was too soon to say whether the findings suggest that a dangerous release of methane looms. In a telephone news conference, she said researchers were only beginning to track the movement of this methane into the atmosphere as the undersea permafrost that traps it degrades.
But climate experts familiar with the new research, reported in Friday's issue of the journal Science, said that even though it does not suggest imminent climate catastrophe, it is important because of methane's role as a greenhouse gas. Although carbon dioxide is a far more abundant and persistent in the atmosphere, ton for ton atmospheric methane traps at least 25 times as much heat.
The paper is behind a paywall for those not in the reporting business, but I will link more as more comes available. If correct, this is not good news - the prior assumption was that increased levels of methane in the arctic were linked primarily to methane bubbling out of freshwater areas - but there's much more methane here to release.
Here's an NSF piece on the potential role of methane in abrupt climate change. I should emphasize here that we have no idea this methane release could cause something similar to occur, but this strikes me as a compelling case for the precautionary principle - precisely because we have no idea.
An abrupt release of methane, a powerful greenhouse gas, from ice sheets that extended to Earth's low latitudes some 635 million years ago caused a dramatic shift in climate, scientists funded by the National Science Foundation (NSF) report in this week's issue of the journal Nature.
The shift triggered events that resulted in global warming and an ending of the last "snowball" ice age.
The researchers believe that the methane was released gradually at first and then very quickly from clathrates--methane ice that forms and stabilizes beneath ice sheets.
When the ice sheets became unstable, they collapsed, releasing pressure on the clathrates. The clathrates then began to de-gas.
"Our findings document an abrupt and catastrophic global warming that led from a very cold, seemingly stable climate state to a very warm, also stable, climate state--with no pause in between," said geologist Martin Kennedy of the University of California at Riverside (UCR), who led the research team.
"What we now need to know is the sensitivity of the trigger," he said. "How much forcing does it take to move from one stable state to the other--and are we approaching something like that today with current carbon dioxide warming?"
Allow me to speak for all of humanity when I say...crap.
Sharon
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I have been worried about this for several years. Too bad if I am right.
Just to correct a misconception you seem to have. There can't be permafrost under the ocean. Permafrost only exists because heat is lost at temperatures below the freezing point of water. When the sea is covering something, it never gets below the temperature of sea water.
Methane under the ocean is trapped as methane hydrate, which has a dissociation temperature a little higher than the melting point of ice. When sea level goes up, the permafrost that is newly covered will thaw and then become permeable to methane.
There is a lot of methane hydrate in more southern parts of the world too. That methane hydrate is only stable because the bottom of the ocean is cold. The bottom of the ocean is only cold because of the global ocean circulation. If that circulation stopped, the bottom would warm due to geothermal heat until it eventually reached the temperature of the surface. That temperature is above the temperature where methane hydrate is stable and so the methane would be released.
If the methane is released rapidly, it would likely get to the surface in a big bubble and have the serious effects on global warming that have been mentioned. That might be better than the alternative; if the methane is released slowly, bacteria might oxidize it using ocean sulfate as the electron receptor producing H2S. There are a few places where a great deal of H2S is released. Essentially no vertebrate life exists at those sites. There have been suggestions that sufficient organic matter in the oceans could cause the production of so much H2S, that the capacity of the atmosphere to oxidize it would be exhausted and the atmosphere would switch to a new state with ~100 ppm H2S. This organic matter could come from primary production, or perhaps from methane.
I thought the "permafrost" terminology was strange too, but if anyone "seems to have a misconception" it is not Sharon who should be blamed for it but the UAK researcher named Shakhova, who was quoted in the press release as referring to "subsea permafrost." I know very little about this stuff (which is apparently properly called methane clathrate, not methane hydrate), and can only speculate that subsurface sediments surrounding large deposits are kept cold enough that they are functionally comparable to on-land permafrost.
Clathrate is a set, Dewey, of which hydrate is a subset. It's more specific to speak of methane hydrate than methane clathrate, altho both terms are appropriate. Hydrate specifies the "host" or lattice molecule.
Got a question. I read that 8,000 years ago, it was so warm that pond turtles and water chestnuts thrived in northern Scandinavia. What happened to the methane?
daedalus2u | March 4, 2010 5:19 PM:
I would like to know why the term subsea permafrost appears frequently in the peer-reviewed literature.
Permafrost, or permanently frozen ground, is soil, sediment, or rock that remains at or below 0°C for at least two years. It occurs both on land and beneath offshore Arctic continental shelves, and its thickness ranges from less than 1 meter to greater than 1,000 meters.
Subsea permafrost occurs close to 0°C over large areas of the Arctic continental shelf, where it formed during the last glacial period on the exposed shelf landscapes. Permafrost is geographically continuous beneath the ice-free regions of the Antarctic continent and also occurs beneath areas in which the ice sheet is frozen to its bed.
llewelly, nice paper, it illustrates the physics of heat transfer and how permafrost under the ocean goes away over time. This will be a source of positive feedback when Greenland melts and sea level goes up by 7 meters, a lot of what is now permafrost will thaw and any methane will be released. Also organic carbon will be released by bacterial action once it thaws.
Once sea level goes up, a whole lot of permafrost is going to melt. The permafrost barrier is not permanant and is not a barrier.
None of the models of global warming take this into account because they don't know how to. They just leave it out. Everyone knows it is not going to be zero, and it is going to make things worse but because no one has any data or theory to figure out how much worse they leave it out.
The real climate scientists know this, the denialists don't care, they quibble over nonsense when anyone who knows anything knows we are in deep doodoo.
It's permafrost.
It's a relict from when sea levels were much lower during the last ice age, which had exposed the continental shelf subaerially to Arctic conditions and created a huge expanse of permafrost.
had the same reaction you had Sharon when I read it this morning - crap. Double crap.
- NASA - Mars methane discovery (Telegraph, 15 Jan 2009)... The Warming Process on Earth and on the Other Planets in Our Solar System... The Neptuneâs moon, Triton is warming (BBC Science & Technology News, July 25, 1999)... Pluto experiences an extraordinary heating (Massachusetts Institute of Technology News, October 9, 2002...
- Carbon emissions creating acidic oceans not seen since dinosaurs (Guardian, 10 March 2009)...
- THE LOGICAL EXPLANATION of the warming process on Earth and on the other planets in our solar system proves to be the one provided by I. Velikovsky, in his book - Worlds in Collision - from 1950: 3600 years ago - âTwo celestial bodies (The Earth and Planet X - A/N) have been attracted one to each other. The inner masses of the Earth were pushed to the periphery. The Earth, with its rotation movement disturbed, started to warmâ:
http://cristiannegureanu.blogspot.com/2010/03/methane-frozen-beneath-ar…
You can download a podcast on this article here:
http://www.sciencemag.org/cgi/content/full/327/5970/1246/DC2
Thanks for the heads up.
Methane emission is not the only cause responsible for climate change. There are several other reasons that are responsible for climate change. We must pay heed towards them to minimize the effect of methane in the atmophere.the weider x factor
Wow, thanks Lukas, not only did you provide us with the supremely obvious and not-really-worth saying tidbit about methane not being the only cause of climate change, but you apparently are offering us a solution in the form of a crappy exercise gimmick. So if we use this stupid resistance band workout, we'll reduce methane in the atmosphere? Wouldn't a buttplug work better (i.e., at all) ?
Don't feed the salestroll.
Hey, I guess we can be happy it's not the anti-atheist spammer that kept addressing things to PZ even though he was commenting on other blogs. daedalus, that giant methane bubble is a very scary idea. I'm not sure if this could happen the same way as a CO2 bubble, but this is a pretty interesting article on what happened at Lake Nyos when a CO2 bubble exploded out of the lake: HowStuffWorks Lake Nyos article
P.S. daedalus, are you SURE there isn't a connection to NO somewhere in there? :)
Yeah, Sharon, this bit caught my eye immediately this morning too. Really bad stuff. I hadn't been aware of the undersea permafrost problem- for sure, that should destabilize before the clathrates do. More to worry about. yay.
What I found even more scary was this reaction from the scientific commentators, reported in the NYT: "It is âindispensableâ to keep track of methane in the region, Martin Heimann of the Max Planck Institute in Germany said"
Yes, indeedy, it's critical that we have a good picture of the train heading straight for us. that'll help. I'm glad we'll be able to publish a nice paper, for all posterity, describing in detail how we went extinct.
Although we've known about clathrates for a good while now, they, and these frozen undersea peats do illustrate one of my own worries- that something big and nasty we're not even thinking about can appear to bite us, as a result of climate collapse.
My favorite line from "The Sting" - Redford, sneering: "They're not as smart as they think they are." Newman, calmly over his shoulder "Neither are we."
hm; or was it "tough"?
Rob, Methane doesn't have a high solubility in water the was CO2 does. The problem in the lake was that the CO2 was dissolved in the water and held their by the hydrostatic pressure of the water above it. When the lake started to mix, the water with a lot of CO2 became depressurized and flashed into gaseous CO2 and water and that has a much lower density so it moves up, displacing water with less CO2. You get positive feedback and the whole lake overturns.
Methane hydrate is a solid, but a sufficiently concentrated solid suspension of it might be able to do the same thing. An undersea landslide might uncover methane hydrate and depressurize it making it unstable and causing more landslides. The pressurizing overburden is solids and not liquid, but fluidized solids could flow out of the way if the hydrates are located on a slope. The decomposition of methane hydrate does absorb heat, so there is cooling which tends to stabilize what is left. I think it would not be as fast as a CO2 overturning. Probably hours or days instead of minutes or seconds.
Excellent analysis, although I can't say I'm comforted by the idea of a shitload of methane coming out in hours or days instead of the explosive seconds of the CO2 though. I should've thought to look up the specific gravity first though, the methane is just a bit more than half the value for air, so if this did happen, it would immediately go to the atmosphere instead of hugging the ground. So it would kill us much more slowly by climate change than immediately by poison ;)
Yeah, methane release makes a perfect tipping point...a good burst of it released from permafrost, if only around for ten years in the atmosphere, in turn causing the release of much, much more; melting all the ice, everywhere, releasing the rest of it.
At which point: we might not get time to publish that paper on our deep understanding of the mechanisms, Greenpa, but then again there'd be nobody left to read it but some assorted jellies, slimes, and fungi.
Maybe next time life ought to try silica-based instead of carbon-based.
Actually, SA, Real Climate does a nice job of putting methane in perspective, compared to CO2. And ocean-released methane is minor, compared to land-based and wetlands release. Didn't know that. All bad enough, but not Hollywood bad.
CO2 on the other hand...
@Greenpa,
"What I found even more scary was this reaction from the scientific commentators, reported in the NYT: "It is âindispensableâ to keep track of methane in the region, Martin Heimann of the Max Planck Institute in Germany said"
Yes, indeedy, it's critical that we have a good picture of the train heading straight for us. that'll help. I'm glad we'll be able to publish a nice paper, for all posterity, describing in detail how we went extinct."
As someone with a definite bias (my spouse is a geophysicist), I think you are being unfair to the scientists. We need scientists to do their jobs - collect data - or we wouldn't know about the train that's heading for us. If we get really smart and figure out how to turn things around*, we'll need scientists to tell us if we've been successful in stopping the train.
*To me, this is where the rubber hits the road, or, um, the train hits the crossing... Some solutions to the climate problem are obvious, but are being blocked for reasons of personal gain. Other problems are more intractable. Even scientists with years of experience have trouble predicting which climate amelioration measures are going to be the most effective (I'm thinking here of Jim Hansen and his attacks on cap-and-trade. Is he right? Who knows.)