4 April 2007

PRESS RELEASE: Arctic Sea Ice Narrowly Misses Wintertime Record Low

Figure 1. Winter Arctic sea ice grows during the winter months, usually peaking in late March. March 2007, shown in a solid blue line, was the second-lowest in the satellite record. High-resolution version

NSIDC scientists announced that the winter 2007 Arctic sea ice maximum was the second-lowest in the satellite record, narrowly missing the March 2006 record (see Figure 1).

Sea ice extent, or the area of ocean that is covered by at least 15 percent ice, was 14.7 million square kilometers (5.7 million square miles) for March 2007, compared to 14.5 million square kilometers (5.6 million square miles) for March 2006, the current record (see Figure 2). The long-term monthly mean for March sea ice extent from 1979 to 2000 is 15.7 million square kilometers (6.1 million square miles).

Scientists monitor the sea ice year-round, paying special attention to 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 freezing up later in the fall and growing at a slower pace in the winter. September usually marks the end of the summer melting season; low summer extent means that ice is melting faster during the summer and leaving less ice to build on during winter recovery.

NSIDC scientist Walt Meier 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."

Figure 2. The pink line indicates the 1979–2000 mean sea ice extent in winter; March 2007 ice extent is indicated by the solid off-white area. Land masses are in green; water is in dark blue. Source: NSIDC Sea Ice Index. High-resolution version

For more information on summer sea ice decline and scientific monitoring of sea ice, see Frequently Asked Questions About Sea Ice.

Media Relations Contact:
Stephanie Renfrow: 303-492-1497, srenfrow@nsidc.org (se habla Español)

The National Snow and Ice Data Center (NSIDC) is part of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado at Boulder.

Additional Information

2006 Summer Sea Ice Minimum Press Release
Arctic Sea Ice Shrinks as Temperatures Rise

2006 Winter Sea Ice Recovery News Release
Winter Sea Ice Fails to Recover, Down to Record Low

2005 Summer Sea Ice Minimum Press Release
Sea Ice Decline Intensifies

2005 Winter Sea Ice Recovery News Release
Arctic Ice Decline in Summer and Winter

NSIDC Sea Ice Index
Images, animations, and trends

All About Sea Ice
In-depth information about sea ice