Punters and pundits call the Arctic Summer Melt

It's that time of the year, when types that think about these things, turn their attention to predicting what this year's lowest Arctic sea-ice extent will be. Eli Rabbet kicks off with a rough round-up of pundits and early predictions. There are rumours of money changing hands.

If none of this makes sense to you, here's the good oil from a Kiwi called Gareth of Hot Topic. And, as a GWW service to the AGW denier trolls who pop in to post, here's your side of the story.

Global Warning Climate Change Energy

Arctic melt season post mortem

From The National Snow and Ice Data Center:

2 October 2008

Arctic Sea Ice Down to Second-Lowest Extent; Likely Record-Low Volume

Despite cooler temperatures and ice-favoring conditions, long-term decline continues

Arctic sea ice extent during the 2008 melt season dropped to the second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on September 14, 2008. Average sea ice extent over the month of September, a standard measure in the scientific study of Arctic sea ice, was 4.67 million square kilometers (1.80 million square miles) (Figure 1). The record monthly low, set in 2007, was 4.28 million square kilometers (1.65 million square miles); the now-third-lowest monthly value, set in 2005, was 5.57 million square kilometers (2.15 million square miles).

The 2008 season strongly reinforces the thirty-year downward trend in Arctic ice extent. The 2008 September low was 34% below the long-term average from 1979 to 2000 and only 9% greater than the 2007 record (Figure 2). Because the 2008 low was so far below the September average, the negative trend in September extent has been pulled downward, from –10.7 % per decade to –11.7 % per decade (Figure 3).

NSIDC Senior Scientist Mark Serreze said, “When you look at the sharp decline that we’ve seen over the past thirty years, a ‘recovery’ from lowest to second lowest is no recovery at all. Both within and beyond the Arctic, the implications of the decline are enormous.”

 Global Warning Climate Change Energy

Arctic sea ice extent running close to record

There is a bet on amongst the climate scientist blogging community, and Stoat is keeping an eye on his investment. He's the one who reckons the record won't be broken this season.

mt called me a "polyanna" (presumably by analogy to "polynyas") for betting on the high side. So let me clarify: my "prediction" was based purely on my reading of the statistics of the time series to-date: a record is rarely followed by another. If we have entered a new regime, then my reasonning is invalid. At the moment, I don't know. The extent is barely above last years, but the ice is thinner, as as NB points out you can see the cracks. Bets are still (formally) open, especially to anyone so confident of low ice that they are prepared to offer 2-1 odds :-), or even odds on extent substnatially (sic or hic?) lower than last year.

Technorati Tags: global warming, climate change, arctic

2008 Arctic sea ice extent — another record low?

Climate Change commented about this six weeks ago.

Meanwhile, Colorado researchers say there is a 3 in 5 chance that 2008 will have a new record low. Mr. Atmoz also has a post on this.

It is my non-quantified opinion that we’ve hit one of the first “tipping points” as far as global warming is concerned, or at least we will over the next few years – a commitment to seasonal loss of arctic sea ice regardless of what we do to CO2 emissions. We’ll be able to see by autumn if summer ice hit a new low, so stay tuned.

Their autumn, our spring. Stay tuned for the autumnal/spring equinox September 22, 2008.