Nick Barnes writes: "Arctic sea ice has reached a record low. Every year sea ice melts through the summer and reaches a low in mid-September. These end-summer lows have been getting lower as the climate warms. The previous record was September 2005, and September 2006 had similar numbers, about 20% below the 1979-2000 average. This year there is less ice than ever before, and the September 2005 record has been broken in early August, with a month or more of melting still to go."