Since the year 2000 the floating ice in the Arctic Ocean has been melting rapidly. Most of the multi-year ice has either melted in situ or has been swept out into more southern waters and melted there. In the Autumn each year the ice reaches its annual minimum before the winter re-freeze sets in again.
In 2007 there was a spectacular fall off in the area of ice due to southerly winds not only bringing warm air over the ocean, but also because the same winds compacted the fractured ice floes together into a minimum area.
Last year the weather pattern was more conventional and the minimum area of Arctic ice was somewhat higher than in 2007, although still far below the 1979-2000 average.
This year, with such little multi-year ice at the start of the year, scientists predict that there could be another record minimum. The graph above from NSIDC shows that the 2009 melt season got off to a slower start than in 2007. However, for the last four weeks the ice has been melting more rapidly than in that record minimum year.
For the time of year, the area of Arctic ice is now less than it has ever been in modern times.
The Melt has slackened off now, so the Arctic ice area has popped back up above the minimum again.
ReplyDelete