Arctic Sea Ice Reaches 2026 Annual Minimum Extent

Arctic sea ice reached its annual minimum extent on Sept. 12, according to NASA and the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder. The ice covered an estimated 1.78 million square miles (4.6 million square kilometers), tying 2008, 2010, and 2025 for the 10th-lowest minimum in the satellite record.

Trent Schindler/NASA’s Scientific Visualization Studio Arctic sea ice reached its annual minimum extent on Sept. The 2026 minimum is consistent with patterns observed in the satellite record. The past 20 years, from 2007 through 2026, have produced the 20 lowest annual Arctic sea ice minimum extents observed since continuous satellite measurements began in late 1978.

Arctic sea ice grows during the dark, cold autumn and winter and retreats as temperatures rise during spring and summer, typically reaching its lowest extent in September. Weather conditions can cause substantial differences in the amount of ice that melts from one summer to another. Over the last decade, for example, increased cloud cover has prevented solar radiation from further accelerating the melt of sea ice, according to Linette Boisvert, a sea ice scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.