It looks like the Arctic ice sheet has reached its yearly maximum – probably sometime in the 3rd or 4th week of February. The extent of ice since then has wobbled around a slightly smaller value as individual weather systems affects the ice sheets. This Northern Hemisphere’s winter ice extent was greater than the all-time low reached in winter 2006-07, but less than the 1979-2000 climatological average. The maximum extent looks to have been around 15 million sq. km. – or between 500,000 to 750,000 sq. km. less than average, but also about 500,000 sq. km. more than the 2006-07 record minimum.
None of this is surprising or unexpected. Nor does it, by itself, prove or disprove anything. I am merely taking note of the state of the arctic ice sheets at their yearly maximum extent. More than once this winter, ice growth stalled for extended peiod of time, as the following time series graph shows:
The extent of the ice sheet graphically looks like this:
The National Snow and Ice Data Center hasn’t issued another news release since two weeks ago – again, this isn’t newsworthy, just noteworthy. Once scientists confirm the maximum areal extent, I’m sure they’ll issue another short report describing recent conditions.
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