“Arctic sea-ice decline is perhaps the best evidence around that something truly unusual is happening to our climate,” Ted Scambos, another NSIDC scientist, said in an e- mail. “Historical records and changes in high Arctic coastal areas that have been icebound for several thousand years indicate that this is not just ‘a bad decade to be ice,’ but something outside the normal range of climate.”
The lowest ice extent recorded in data dating back to 1979 was the 4.1 million square kilometers posted on Sept. 16, 2007. This year’s lowest point will probably be 4.3 million to 5.3 million square kilometers, according to Scambos, who said it was a “personal estimate.”
Almost a 25% spread!
The latest melt is in part a result of temperatures in May through July that were 1.5 degrees Celsius (2.7 Fahrenheit) to 2.5 degrees higher than average, according to Scambos. The most recent daily data, for Aug. 3, show ice covering 6.57 million square kilometers, putting it back above the equivalent level in 2007, he said.
Antarctic sea ice, which is much more driven by the wind, is “slightly” below the average for this time of year, according to Scambos.
Arctic ice is almost completely driven by the wind. What does that mean?