Posted by: billlaurelmd | September 3, 2008

Late post: North Pole 31 August 2008

Well, actually Sunday, but I’ve been having problems with my computer’s connectivity (some sort of software conflict, I think…), but that’s neither here nor there. Two pictures from yesterday from the North Pole webcams; first, the fisheye view looking up:
NOAA webcam #3, arctic sea ice, 31 August 2008, 2008 melt season
The panoramic camera #1 has been screwed up during this past week, pointing toward the sky without much if any view of the surface. Here it is anyway:
NOAA North Pole webcam #1, 31 August 2008

Temp is -1.5°C, or 29°F.

The 2008 melt season time series (below) shows that over the last few days, the decrease in area covered by arctic sea ice (15% in a 25 km2 square) seems to have stopped, at least temporarily:

Arctic sea ice extent, 31 August 2008

The time series is an average over several days and is therefore subject to correction, as we’ve seen in past diaries of mine (including [http://www.dailykos.com/storyonly/2008/8/27/9468/39300/305/576328 the one earlier this week] when we passed 2005 as the second least ice concentration in the satellite record).

During this season, we’ve seen that when sea ice concentrations drop toward the 15% threshold of sea ice vs. no sea ice, by the next week that’s the area with big sea ice loss. The sea ice concentration maps below comparing this week to last week (and this year to last year) are in the table below:

Sea ice concentration, 8/31/08 Color legend, % conc. Sea ice concentration, 8/31/07
Arctic sea ia Photobucket Photobucket
Sea ice concentration, 8/24/08 Color legend, % conc. Sea ice concentration, 8/24/07
Arctic sea ice concentration/extent, 24 August 2008 Photobucket arctic sea ice, 24 August 2007, 2007 melt season

The area coverage of low ice concentration seems to have decreased somewhat; we may be nearing a bottom in sea ice concentration. I think the chances we’ll break last year’s record this year are dropping quickly, though a change in arctic atmospheric flow regime may change that.

By the way, both the northwest (through the Canadian archipelago) and the northeast (through the area north of Siberia) passages are open for the first time according to [http://www.spiegel.de/international/0,1518,574815,00.html this article in Der Spiegel], though the ice guys want to make sure before they make it official. It’s also the first time the Northwest Passage has been open two consecutive years.

Of note from that article: the opportunity for profit:

The ever-thawing Arctic represents a potentially major opportunity for the shipping industry. Currently, there are only between 20 and 30 days a year in which the Northeast Passage is 50 percent covered by ice or less … But the Arctic Climate Assessment from the year 2005 estimates that such days will become increasingly frequent — with up to 120 largely ice-free days by the end of the century. And that is likely a conservative estimate.

This of course, assumes there is oil or some other energy source to run those ships, a highly questionable assertion, but that’s a subject for a different diary entirely.

Regardless of anything else, we’re at about 5.0 million km2 of sea ice, second only to last years 4.3 million km2. I’ll keep up with these diaries, let y’all know when we hit the minimum for 2008 (we’ll only know that after the fact), and report on the “refreeze”. If it’s not as fast as last year’s, that’ll have a significant impact on next year’s minimum concentration.

UPDATE: 9/3/08

The drop in sea ice coverage has increased again to a slightly faster pace than last year. More low concentrations of sea ice are showing up today at the fringes of the ice field, and both northwest and northeast passages are still open, making the Arctic sea ice unattached to any of the major continents. This season is the first time that one could reasonably safely circumnavigate the Arctic Ocean for a *very* long time.

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