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Thu May 7, 2015, 06:45 PM

the increasing rate of thawing of the permafrost a huge unknown - how much will it accelerate GW?

http://www.dailykos.com/story/2013/06/14/1216170/-Arctic-Methane-found-at-Amazing-Levels-by-NASA#
(emphases my own)

Over hundreds of millennia, Arctic permafrost soils have accumulated vast stores of organic carbon - an estimated 1,400 to 1,850 petagrams of it (a petagram is 2.2 trillion pounds, or 1 billion metric tons). That's about half of all the estimated organic carbon stored in Earth's soils. In comparison, about 350 petagrams of carbon have been emitted from all fossil-fuel combustion and human activities since 1850. Most of this carbon is located in thaw-vulnerable topsoils within 10 feet (3 meters) of the surface.

But, as scientists are learning, permafrost - and its stored carbon - may not be as permanent as its name implies. And that has them concerned.

"Permafrost soils are warming even faster than Arctic air temperatures - as much as 2.7 to 4.5 degrees Fahrenheit (1.5 to 2.5 degrees Celsius) in just the past 30 years," Miller said. "As heat from Earth's surface penetrates into permafrost, it threatens to mobilize these organic carbon reservoirs and release them into the atmosphere as carbon dioxide and methane, upsetting the Arctic's carbon balance and greatly exacerbating global warming."

Current climate models do not adequately account for the impact of climate change on permafrost and how its degradation may affect regional and global climate. Scientists want to know how much permafrost carbon may be vulnerable to release as Earth's climate warms, and how fast it may be released.



research published in Nature, April 15, 2015 points out that as microbes break down the organic material in thawed permafrost they generate more heat and will speed up the process of melting more permafrost - with greater release of carbon dioxide and methane.

http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2590.html
Abstract

Decomposition of organic carbon from thawing permafrost soils and the resulting release of carbon to the atmosphere are considered to represent a potentially critical global-scale feedback on climate change1, 2. The accompanying heat production from microbial metabolism of organic material has been recognized as a potential positive-feedback mechanism that would enhance permafrost thawing and the release of carbon3, 4. This internal heat production is poorly understood, however, and the strength of this effect remains unclear3. Here, we have quantified the variability of heat production in contrasting organic permafrost soils across Greenland and tested the hypothesis that these soils produce enough heat to reach a tipping point after which internal heat production can accelerate the decomposition processes. Results show that the impact of climate changes on natural organic soils can be accelerated by microbial heat production with crucial implications for the amounts of carbon being decomposed. The same is shown to be true for organic middens5 with the risk of losing unique evidence of early human presence in the Arctic.



Here's the whole paper: http://www.nature.com/articles/nclimate2590.epdf?referrer_access_token=aZJygArBfYYSiUzB60TqbNRgN0jAjWel9jnR3ZoTv0M-PY6I018KtzmgQoAY5EQbmH76TfMseb9NFOSHHqdzKJm_9NtSZ_chqLlF3XZh5tJmNTjj6z22l6mKbdk6TcbKG2bVCK8Mh6MSBH88MUG6-GF-t4HNRT-0fhBSSSyU5-NFba_qY5Je4QkMRiGCevx5_3nHpHSSE9FoPj6-fHdHse-1sAUlSHT1-CMf97IVH-BIUa1s4O5tJ61MxjPt1E4r&tracking_referrer=grist.org



GW is accelerating. I haven't been able to find an estimate for the GHG production for the permafrost and a prediction of how fast it is growing (they may not have enough data to make what scientists consider a reliable estimate yet). But it is definitely accelerating. At some point in the future, if efforts at combating GW continue at the current pace, the World-wide annual release of CO2 and methane will be greater than what we will be able to reduce GHG production per year. It could get to the point that even if we could cut GHG emissions to zero, the planet will continue to warm on its own. At that point, you could say we will have reached the point of no return. And that is why we don't have the luxury of taking 20 to 30 years to achieve modest reductions in GHG emissions. With accelerating production of GHG emissions, a given amount of GHG reductions achieved sooner will have a greater impact than that same amount of GHG reductions achieved later.


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Reply the increasing rate of thawing of the permafrost a huge unknown - how much will it accelerate GW? (Original post)
Bill USA May 2015 OP
Binkie The Clown May 2015 #1
Systematic Chaos May 2015 #3
OnlinePoker May 2015 #4
Systematic Chaos May 2015 #5
Binkie The Clown May 2015 #6
daleanime May 2015 #2

Response to Bill USA (Original post)

Thu May 7, 2015, 08:19 PM

1. Any gardener who has ever made a compost heap

knows how hot organic material very quickly gets once the microbes go to work. A little bit of warming turns into a whole lot of warming once that critical tipping point for microbial actions is passed.

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Response to Binkie The Clown (Reply #1)

Fri May 8, 2015, 08:32 AM

3. I have never done any gardening, nor handled a compost heap.

Therefore, would you please take a moment to explain for me (and people like me) exactly how warm this stuff can get? Are we talking room temperature? Sauna? Or somewhere in between?

I don't know the first thing about this, so I would appreciate your time to offer an explanation.

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Response to Systematic Chaos (Reply #3)

Fri May 8, 2015, 09:18 AM

4. Optimum temperature range in the pile is around 150F

This kills off all the seeds and pathogens. Once the temperature of the pile drops, you then turn it to circulate material on the outside of the pile and temperature spikes a second time.

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Response to OnlinePoker (Reply #4)

Fri May 8, 2015, 11:48 AM

5. Holy shit.

Perhaps literally....

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Response to OnlinePoker (Reply #4)

Fri May 8, 2015, 12:32 PM

6. That's correct ^^^

Hay stacks have been known to burst into flame if not properly ventilated.

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Response to Bill USA (Original post)

Thu May 7, 2015, 09:06 PM

2. kick, kick, kick....

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