Arguments
‘Frozen Dirt’ and Methane … ‘We Cannot Go There’
Posted on 3 March 2013 by greenman3610
This is a re-post of Peter Sinclair's latest video at the Yale forum on climate change & the media
Concerns about escape of CO2 and methane from Arctic permafrost revolve around whether, how much, and how fast emissions could be released. But a new Yale Forum video cautions that a warmer atmosphere poses real risks and, once started, such a release ‘will just go by itself.’
“Frozen dirt.”
Got it? If so, now you can better describe permafrost in those discussions around the dinner table. It’s any underground earth material that stays frozen for two or more consecutive years, Vladimir Romanovsky, Ph.D., of the University of Alaska Fairbanks, explains in a new “This is Not Cool” video produced by Peter Sinclair for The Yale Forum on Climate Change & The Media.
When it thaws, so do the microorganisms. With no oxygen, the microorganisms make methane, and with it they make carbon dioxide, Kevin Schaefer of the U.S. National Snow and Ice Data Centre explains.
The concern is that much of the carbon stored in permafrost — in frozen dirt — could be released into the carbon cycle, says scientist Charles Miller of NASA/Jet Propulsion Laboratory. The Arctic, Miller says, is being affected by warming faster and more significantly than models had predicted. Methane concentrations, and even CO2 concentrations, “that one might associate with flying near a large oil or natural gas production facility or even flying through the middle of a large city” can be observed from an airplane, he says. “They’re elevated that much. But when you look down at the surface, all you see is pristine wilderness, typically wetlands and rivers with sporadic forests and grassland.” Finding those concentrations so distant from those locations, Miller says, is “quite remarkable to me.”
It all comes down to how much of the carbon currently stored in the Arctic tundra will be released and over what period of time, Miller says. Will it be released over 100 or 150 years, or over a decade or two?
In the latter case, “the perturbation would be significantly larger,” Miller cautions.
“We have at least theoretical control” over human emissions of greenhouse gases, Romanovsky says. “And because of that, we feel that we can do something to change it if it’s necessary.
“In the case of thawing permafrost, there’s no way to control it or stop it. It just will go by itself.”
Nobel Laureate and former Energy Secretary Steven Chu cautions of “a reasonable possibility” that once started, emissions from Arctic permafrost could “even dwarf” human-caused GHG emissions. Chu expresses concerns in particular about global temperature increases of 4, 5, or 6 degrees C. “At that point, it’s completely out of our control … the release of the trapped carbon material in the Tundra just runs away …. We cannot go there.”
But might we? Anton Vaks, of Oxford University and colleagues have published a paper cautioning that the “tipping point” for permafrost melting may be quite lower, more like 1.5 degrees C above preindustrial global temperatures. “This is probably the tipping point,” Vaks cautions. (Since the late 1800s, global temperatures have increased about .8 degrees C.)
But “it’s not an all or nothing” situation, scientist Ben Abbott of the University of Alaska Fairbanks says. Limiting CO2 and greenhouse gas emissions will lead to lower releases of greenhouse gases from the permafrost, he says.
In that case, one can hope that it will be little more than “frozen dirt” in the first place. But it’s a big “If.”
Schaefer has said that permafrost tipping pt might be only 15 years from now. That was before some new research in Feb this year showing that permafrost carbon exposed to sunlight turns into CO2 40% faster. All of which is to say: time to wound down the use of fossil fuels.
More detailed press release of the most interesting detail of this video: 1.5C being the "tipping point" of the large PF melt (based on the stalactites growth radioactive dating by Anton Vaks) can be found here in Oxford Uni press in Science 21 Feb 2013, DOI: 10.1126/science.1228729if you have an access.
Interesting study worth close attention. Confirms Jim Hnasen's opinion that "danegerous" level of global warming is not beyond 2 degrees: we should limit it to 1 degree to avoid the "danger".
How do we stop the methane and carbon dioxide that is already escaping from permafrost areas, bubbling up from these pristine lakes and the invisible releases from other areas of permafrost?
Sadly, we don't. Those emissions will continue, just as surely as there is an energy imbalance at the TOA. Polar amplification will continue to cause more warming of the permafrost with yet more attendant releases of CO2 and CH4.
At least the Kraken does not yet wake...
The only statement arousing dissonance with my mental model is "much of the carbon stored in permafrost — in frozen dirt — could be released into the carbon cycle." I usually consider permafrost a subsubcompartment of the soil subcompartment of the lithosphere compartment in my four-compartment model of the carbon cycle. The permafrost carbon is already in the carbon cycle in my understanding. From my view of the carbon cycle, the point here is a change in one component of the flow of carbon from the lithosphere to the atmosphere. I recall some suggestions from work in Alaska that a significant part of the current surface methane releases to the atmosphere in some places in Alaska is in fact deep methane (very old ex-biomass carbon, aka fossil fuel). One of the ideas in that paper was that fracturing resulting from crustal stress changes due to melting glaciers allows the deep methane to migrate toward the surface where it may be trapped for a while under an impenetrable layer of permafrost. Local thawing of the permafrost produces holes in the permafrost layer through which the trapped old methane continues its migration to the surface.
Regarding the 1.5 degree tipping point, my recollection is that the 1.5 degree temperature increase corresponds to no permafrost at 60 degrees North latitude in a part of Siberia.
The essay ignores the elephant in the room – methane trapped in clathrate and as gas in surrounding sediments beneath permafrost covering the seabed of the Siberian Continental Shelf. This has been quantified by Shakhova and Semiletov as comprising not less than 1,700 gigatonnes. As a result of seabed permafrost degradation methane has been observed venting to the atmosphere. Because of the shallow depth of water covering the continental shelf, it has no time to oxidize to far less potent CO2.
Continuing loss of sea ice and Arctic Ocean warming, combined with atmospheric warming is likely to result in accelerated loss of seabed permafrost, increasing venting of methane to the atmosphere. This has the potential to reduce sub-seabed pressure, destabilise shallow clathrates, rapidly increasing methane excursions from them to the atmosphere, further amplifying Arctic temperatures and chnaging global climate.
Daniel Bailey rightly observes that “the Kraken does not yet wake... “ But it is already stirring and nothing short of reversing Arctic warming is likely to prevent it (methane) from venting to the atmosphere in such volume as to bring about rapid and permanent climate change before 2100.
Do I hear mutterings about geo-engineering – spraying sulphides at the top of the stratosphere - to prevent this? The clothing industry could produce a whole new range that can withstand acid rain and we could all get on with business as usual.