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Colorado Bob

Greenland

Sharyn Alfonsi reports from the top of the world on one of the most significant efforts to study climate change happening today

http://www.cbsnews.com/news/greenland-60-minutes-climate-change/

Colorado Bob

As the ‘blue Arctic’ expands thanks to global warming, an icebreaker finds no ice to break

During a recent mission off the Arctic archipelago of Svalbard, a Norwegian Coast Guard icebreaker encountered unusual winter conditions for an area just 800 miles from the North Pole.

At this time of year, sea ice usually closes in around Svalbard’s northern and eastern coasts. But not this year. The sturdy 340-foot-long, 6,375-ton KV Svalbard had no ice to break, reports Oddvar Larsen, the ship’s First Engineer.

I spoke with Larsen and other sailors on board the icebreaker during the kickoff event of the 10th Arctic Frontiers conference in Tromsø, Norway on Jan. 24, 2016. This is the first post of several I have planned based on reporting I did at the conference.

http://blogs.discovermagazine.com/imageo/2016/01/30/an-icebreaker-with-no-ice-to-break-in-blue-arctic/#.VrCMP1K7T6M

Jim Hunt

Bob - See also:

http://forum.arctic-sea-ice.net/index.php/topic,1377.msg69266.html#msg69266

et seq.

VaughnA

As the permafrost layer thaws and as the organic material there decays via microbes heat is generated by this process. I have searched for some information on this topic but so far I have come up empty handed. It would seem that as the thaw layer deepens more heat would be generated with less heat escaping to the surface thereby heating deeper permafrost. With warmer air temperatures and with some decay generated heat not escaping to the surface due to more and more heat being generated at deeper and deeper levels as more permafrost thaws it follows that this could become a self sustaining process. The heat generated by the decay itself then could continue to thaw the deepest permafrost creating a rapid decay of deep organic layers until the supply of organics was exhausted. If this scenario is true then large amounts of methane and carbon dioxide would be released into the atmosphere quite rapidly.

Questions:
1. How much heat is actually generated by the decay process.
2. Is it enough to become self-sustaining?
3. Would a process I described be enough to significantly alter the thaw/decay process?


Rob Dekker

VaughnA, interesting reasoning.
For your question 1, an upper bound would be the heat value of methane, which is something like 1000 btu/ft^3 (some 18 MJ/m^3).
For question 2, you would need to know the "density" of methane release in certain areas of the Arctic, as well as the heat insulation value of the water and ice above. I have not looked into that, but maybe this helps as a starting point to see if your theory has merit.

Rob Dekker

Sorry. That is 38 MJ/m^3.

Neven

VaughnA, I have received an answer to your question via mail from Christian Knoblauch of the University of Hamburg:

A quick response. There are two papers that have modelled microbial heat production in permafrost (Khvororstianov see attached) and one published last year (Hollesen, J., H. Matthiesen, A. B. Moller, and B. Elberling (2015), Permafrost thawing in organic Arctic soils accelerated by ground heat production, Nature Climate Change, 5(6), 574-578.) that measured them. To my view the Kvorostianov papers overestimate heat production since they use the heat production generated from chemically oxidizing glucose which is not the most common substrate in permafrost soils. I hope this helps
VaughnA

Thanks, Rob and Neven.

It sounds like there is a considerable potential for heat production in organic permafrost. The bigger question I have is whether or not the process can be "self-sustaining." I hypothesize that wherever it becomes self-sustaining the thaw will be much more rapid than if/where it is not self-sustaining. Maybe some answers will come from this workshop. In any case the problem sounds very serious and this workshop should give us a better idea about this seriousness.

A-Team

VaughnA brings up a potentially significant positive feedback mechanism for more rapid metabolism of thawed anaerobic permafrost.

We’re all familiar with the steaming hot pile of wet autumn leaves and spontaneous combustion of oily rags. The first is self-limiting as the temperature comes to exceed microbial growth tolerances; the latter involves direct oxidation of organic solvents by molecular oxygen.

Both are irrelevant to methane production from permafrost which requires not only strict anaerobiosis (lest the nickel catylyst in F430 be poisoned) but also exhaustion of other terminal electron acceptors such as sulfate, ferric iron and nitrate.

The carbon sources in peat soils, though already more oxidized than monosaccharide, are abundant, so not likely rate-limiting to archael doubling times -- it is more the number of ATP's that can be made from a molecule of say glucose (which drops from ~38 with O2 around to 1-2 from tannic acid in a fermentative process. Methanogenesis, the final stage of decomposition of organic matter. needs carbon dioxide (or acetate) as electron acceptor and the former will be abundant.

Metabolism does indeed move faster at higher temperature in accordance with the Q10 (Arrhenius, 1889) but the effect is limited: a 10º C rise will only halve the doubling time of a facultative psychrophil. A microbe really specialized to low temperatures will struggle at higher temperatures.

Thus while the effect is real -- microbial growth raises temperature fostering more rapid growth which furthers temperature increase -- but it will not be a runaway situation in thawing permafrost whose heat capacity (responsiveness to metabolic heat input) is very large relative to the slow inputs that can be expected.

Colorado Bob

Atmospheric CO2 Rocketed to 405.6 ppm Yesterday — A Level not Seen in 15 Million Years

http://robertscribbler.com/

Colorado Bob

Glaciologists anticipate massive ice shelf collapse

A team of researchers is traveling to a rocky outcrop in Antarctica to study a massive ice shelf that could crash down around them before the end of March.

University of Alaska Fairbanks glaciologist Erin Pettit said that an ice shelf about 1,000 feet thick and a third the size of Rhode Island is on the verge of shattering into millions of icebergs during February or March, the end of Antarctica’s summer. If it does, the lead researcher and her team will be within viewing distance in a place they hope doesn’t live up to its name — Cape Disappointment.

http://news.uaf.edu/61609-2/

Colorado Bob

This is how the permafrost thaws.

Wolverine Lake Thermokarst Timelapse

Published on Aug 18, 2014
Time-lapse video of the thaw slump at Wolverine Lake on the North Slope of Alaska. The thawing permafrost and chunks of vegetation all end up in the nearby lake.
(1 photo every 5 minutes, playback at 20 fps)

https://youtu.be/4fCAcoy0X0M

VaughnA

Thanks A-Team that is very helpful It sounds like you are saying that a fair amount of heat is generated. Wouldn't heat generated a few meters underground be conducted both upwards and downwards preventing deeper freezing during the winter and continue thawing deeper as well due to close proximity to deeper frozen material?

The video you supply the link to Colorado Bob shows the top layer sloughing off, certainly another part of the thawing process. My guess is that we are headed for "one hell of a mess."

AbbottisGone

VaughnA, can I ask which statistic most fiercely drives the point home about the idea that, 'we are headed for "one hell of a mess."'?

VaughnA

Abbotisgone, I think the quote from Kevin Schaefer at the NSIDC says a lot:

"There is a huge amount of carbon stored in permafrost. Right now, the Earth's atmosphere contains about 850 gigatons of carbon. (A gigaton is one billion tons—about the weight of one hundred thousand school buses). We estimate that there are about 1,400 gigatons of carbon frozen in permafrost. So the carbon frozen in permafrost is greater than the amount of carbon that is already in the atmosphere today."

https://nsidc.org/cryosphere/frozenground/methane.html

This is completely freaky. Methane and carbon dioxide would increase dramatically if even half of this got into the atmosphere. Temperatures would increase how much??? In the Arctic the increase would be on the order of at least twice as much as mid-latitudes. This would cause how much Arctic sea ice to melt, how much of Greenland to melt, not to even mention Antarctica?

I live 302 feet above sea level. However, are we going to get tsunamis from Antarctica this large if the ice sheet collapses like a pile of Jenga blocks?

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