I've been wondering how the different effects of summer wild fires net out. On the one hand, the smoke and ash in the atmosphere block some solar rays. Because most of the fires are in the summer, this should be a significant negative feedback. When the pollution settles onto the earth, it will produce positive feedbacks which vary according to the surface. Darkened sea ice and glaciers retain significant extra heat. Is there any math out there that simulates these effects by location and time of year ?

Don't lump people who question the Warren Report with your other lunatics !

How much rain typically falls under Arctic Ocean lows this time of year ? I would think significant rainfall on thin, patchy ice could cause as much destruction as wind.

It hadn't occurred to me that there would be so much debris and sediments ripped out of Greenland by the raging meltwater. This will widen channels and speed up glacier movements year-round and could be a significant positive feedback for GIS disintegration.

When the Greenland lakes drain, some of the water makes its way to the oceans, while some descends through the ice sheet and refreezes. I believe that experiments have been done by researchers putting instruments and/or substances into moulins. Have any results been published as to what percentage of meltwater reaches the sea ? I believe this could be an important parameter as the number and size of lakes steadily increases.

In another 4-5 billion years, our sun will be a red giant and grow outwards, making it very hot on earth. Therefore, the next thousand or so ice ages, along with the intervening interglacials, are just noise along this warming path. The best planning we can do is to try to project which continent will drift to one of the poles in 4 billion years, and buy land there.

Most of the northern U.S. and Southern Canada has zero or little snow cover right now. This is unusual for early February. Anecdotally, late winter and early spring temperatures are correlated (inversely) with snow cover where I live in Southern Ontario. I wonder how much the reduced albedo will impact this year's March-April temperatures. I know there are localized effects (normally, fast-melting snow suppresses daytime temperatures on otherwise warm days ; not this year it seems) as well as more widespread effects from the lower albedo.

4000 km3 not 4 million.

What strikes me is that there is not that much motion of the ice. For all the discussion of gyres, pressure gradients and currents, most of the ice melted in place this year.

Kevin, I read the summary of the paper and I think I get the gist of it. Perhaps the pattern of decreases and increases will produce few large negative changes and frequent small positive ones. But if extent goes to zero in 50-60 years I doubt if there will be but a few cherry-picked decade-long periods where extent has increased (consider the anomaly of the 1998 to 2008 global air temperature drop versus all the positive decadal changes since the late 1970's). The paper said the chances of a decrease or increase in sea ice over a random decade are "equal". I don't buy it. Mike.

Yes. But the line is going from current value to zero in a few decades, so the slope of the expected ice extent (or area or volume) is always negative. This means that it is more likely that extent will decrease than increase in any given short-term time frame. Even if variability is extreme.

TZ : You had me looking for "Fulder"'s paper which is about marijuana. I believe you meant the "Funder" paper about driftwood. I haven't read it either but maybe I'll give it a try. Mike.

I am not sure which paper you are referring to but I haven't read it. It just doesn't seem possible that the probability of an increase is "equal" to the probability of a decrease in the short term when the slope of the expected amount of ice is always negative, regardless of the variability. Perhaps the function is of such complexity that it is "expected" that there will be reversals but I would need to be convinced of that. Mike (yahoo assigned me this stupid moniker and I don't know how to change it).

"The simulations also indicated that Arctic sea ice is equally likely to expand or contract over short time periods under the climate conditions of the late 20th and early 21st century". I don't see how this can be mathematically true. Even if AGW is only responsible for half of the sea ice loss since 1980, that is something like 3 1/2% per decade. Whatever the standard deviation of the annual ice change is, the expected value is still a loss, with a higher probability of loss than gain in any given year. The probability of net ice loss increases for longer periods of time, eventually approaching 100% (the house always wins eventually).

If you look closely at the satellite image for July 8 you will see a lonely polar bear on an ice floe near the north pole holding a small sign that says "HELP PLEASE".

Temperatures for April and May in Churchill, Manitoba and Iqualuit, Nunavit averaged significantly below normal. The ice on Hudson Bay was thin but started melting late.