For anyone who’s betting that 2008 meltback will exceed 2007 meltback, I think that you’ll be able to pretty much know where you stand by the end of this week and your chances are not looking good right now based on this week’s exit polls. Another Climate Audit first.
The plot below shows the daily meltback for the last 5 years. 2007 is in red, 2008 in black. Notice the surge in 2007 at the end of June and beginning of July. We’re at julian day 182 today – July 2, 2008.
The most intense melt occurred last year between day 179 (June 29) and day 184 (July 4) with 160,000 sq km meltback on day 182 (July 2) and over 200,000 sq km on day 183 (July 3). This year’s a leap year, so that July 2 is already day 182 and was only 90,000 sq km. As of yesterday, 2008 was about 510,000 sq km behind 2007 and it looks like it is losing ground day by day in the first week of July – a big melt week where it has to make time.
Today (day 183) and tomorrow (day 184) will probably tell the story. I’ll do daily updates for the next few days – it will be interesting to watch.
Both realclimate and William Connolley have recently (June 27, June 28) done posts on Arctic sea ice with neither pointing out that we were beginning a fairly critical melt week. (Connolley bet against a 2008 record.)
Update: Here’s a graphic that may show my guess a little more clearly. Here I’ve shown a smooth of the average melt (lowess with f=.2) for the average of the period with online daily information at the website linked here, 2007 and 2008. I realize that high melt periods can vary a bit, but sometimes in a pennant race one team build an insurmountable lead. My guess is that 2007 already has an insurmountable lead over 2008.