The team found that during episodes of rapid sea-ice loss, the rate of Arctic land warming is 3.5 times greater than the average 21st century warming rates predicted in global climate models. While this warming is largest over the ocean, the simulations suggest that it can penetrate as far as 900 miles inland. The simulations also indicate that the warming acceleration during such events is especially pronounced in autumn. The decade during which a rapid sea-ice loss event occurs could see autumn temperatures warm by as much as 9 degrees F (5 degrees C) along the Arctic coasts of Russia, Alaska, and Canada.

Lawrence and his colleagues then used the model to study the influence of accelerated warming on permafrost and found that in areas where permafrost is already at risk, such as central Alaska, a period of abrupt sea-ice loss could lead to rapid soil thaw. This situation, when summer thaw extends more deeply than the next winter’s freeze, can lead to a talik, which is a layer of permanently unfrozen soil sandwiched between the seasonally frozen layer above and the perennially frozen layer below. A talik allows heat to build more quickly in the soil, hastening the long-term thaw of permafrost.

They say that “Arctic soils are believed to hold 30 percent or more of all the carbon stored in soils worldwide.”

OK, it’s only working the models, so let’s hope they made a big mistake!

Anyway the next post in the series on what the IPCC did is now up.

Of broader implication I recall Hansen in 2003 pointing out that rain moving further north is one way that heat is transported from warmer oceans to northern lands. Increased rain at higher latitudes is an effect already observed.

Hansen also emphasises the growth of forests on tundras further north as a long term feedback, along with the loss of albedo through the loss of ice. He hasn’t explained it in detail that I’ve seen, but I think the idea is that the darker forests absorb more solar radiation than the open tundras and that this effect is greater than any draw-down of carbon from the extra growth. He regards it as very significant longer term.

Soylent Green is people. http://en.wikipedia.org/wiki/Soylent_Green

You should have seen the look on his face when i suggested the greatest untapped resource on the planet is dead people. You could eat ‘em, make fertilizer, burn ‘em for fuel…i mean if you are going to recycle, lets go the whole hog
(my apologies to any dead people reading this post).

BTW my son, the one who lives here, has a bike computer, which he calibrated against Mt Coot-tha. It’s probably a bit rough but it tells him what the elevation is. Our place is 80m above sea level, which might give us a nice beach-side place in a thousand years or so. But 90% plus of Brisbane would be under water if his computer’s right.

I told him i was doing this on purpose to increase land fill, so we have something to stand on when sea levels rise.

He just shook his head and walked away.

True story.

Nick, this post was originally part of a larger one on sea level rise, which is where I’m headed, so I didn’t look at the other implications of Arctic melting. You are right, plenty of people, nations and corporations are salivating over the opportunity to extract hydrocarbons from the area. Remember the Russians planting their flag on the sea floor at the north pole?

Peter, apart from methane Tim Flannery reckons the warming of the Arctic might change what he calls “zonation” more rapidly:

The second thing is of course that the entire climatic zonation of the northern hemisphere is held in place by the thermal gradient between the pole and the equator. That’s why we have deserts where we have them in the northern hemisphere, and we have forested areas where we have them and tundra where we have them. And when I look at the melting tundra, the advance of the forest northwards…Greece and its forest fires that look like that area’s becoming hostile to the sort of vegetation. I think we’re seeing the early stages of a shift in that zonation. Once the ice melts away entirely and we get a rapid warming of the Arctic Ocean, that’s when you’ll see those sorts of changes potentially start shifting much more quickly.

Excellent point Nick. Cheney seems very excited about future prospects for Wyoming due to global warming…so I imagine Bush & the oil men are thinking same about the ability to gain access to previously unpenetrable &/or hostile areas. North-West passage and all that:

http://www.backpacker.com/blogs/199

Not surprising the Canadian PM is establishing further military & security links w/ Inuit.

According to Lawrence, D. M., A. G. Slater, R. A. Tomas, M. M. Holland, and C. Deser (2008), Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss, Geophys. Res. Lett., 35, L11506, doi:10.1029/2008GL033985:

Coupled climate models and recent observational evidence suggest that Arctic sea ice may undergo abrupt periods of loss during the next fifty years. Here, we evaluate how rapid sea ice loss affects terrestrial Arctic climate and ground thermal state in the Community Climate System Model. We find that simulated western Arctic land warming trends during rapid sea ice loss are 3.5 times greater than secular 21st century climate-change trends. The accelerated warming signal penetrates up to 1500 km inland and is apparent throughout most of the year, peaking in autumn. Idealized experiments using the Community Land Model, with improved permafrost dynamics, indicate that an accelerated warming period substantially increases ground heat accumulation. Enhanced heat accumulation leads to rapid degradation of warm permafrost and may increase the vulnerability of colder permafrost to degradation under continued warming. Taken together, these results imply a link between rapid sea ice loss and permafrost health.

Never mind ‘our children’, some of us here are young enough to have known about the problem for quite a while, tried to increase awareness about it and make a personal contribution to reducing the problem and are still going to have to live through the majority of our lives (should we live to life expectancy as currently is) in a climate created by wilful greed and stupidity.

Aaaaaaaaaaaaaaaaaargh!

Paul, thanks for the link.

I have in mind a wrap up post at the end, which could be sent off to policy makers - Peter, Penny, Marn, Ross Garnaut etc - to pick up BilB’s point.

Meanwhile if anyone in commenter-land wants to draw what’s posted on this blog to the attention of policy makers, I can’t imagine it would do any harm.

by varying the relative length of the axes, chopping off the bottom so that the trend appears to be approaching zero etc

Please don’t resort to the techniques beloved of pharmaceutical companies - the drop in the sea ice minimum is sensational enough and doesn’t need this visually deceiving treatment.