Posted on April, 01 2007

National Snow and Ice Data Centre (NSIDC) scientists announced that the maximum extent of arctic sea ice in winter 2007 was the second-lowest in the satellite record, narrowly missing the March 2006 all-time lowest record.

Sea ice extent, or the area of ocean that is covered by at least 15 percent ice, was 14.7 million square kilometres (5.7 million square miles) for March 2007, compared with 14.5 million square kilometres (5.6 million square miles) for March 2006, the current lowest record. The long-term monthly mean for March sea ice extent from 1979 to 2000 is 15.7 million square kilometres (6.1 million square miles).

Scientists monitor arctic sea ice year-round, paying special attention to its extent during March and September. March usually marks the end of winter in the Arctic, a period when sea ice grows, or recovers, from the summer minimum.

Low winter recovery means that the ice is forming later in the autumn and growing at a slower pace during winter.

September usually marks the end of the summer melting season; low summer extent means that sea ice is melting faster during summer, leaving less ice to build on during winter recovery.

Walt Meier, NSIDC scientist, said: “This year’s low wintertime extent is another milestone in a strong downward trend. We’re still seeing near-record lows and higher-than-normal temperatures. We expect the downward trend to continue in future years.”