Daily images of ice cover in the Arctic Ocean show sea
ice melting around the pole from March 15, 2026 to Sept. 12, 2026.
Trent Schindler/NASA’s Scientific Visualization Studio
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.
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.
That has contributed to relatively
stable September sea ice extent in recent years. “We’ve plateaued, but we’re
still low relative to the earlier part of the record,” said Walt Meier, a
senior research scientist at NSIDC.
Antarctic
sea ice extent approaches annual maximum
At the opposite end of the planet,
Antarctic sea ice is approaching its annual maximum following a fluctuation
during August.
Sea ice around Antarctica declined by
roughly 116,000 square miles (300,000 square kilometers) over a six-day period
before resuming its seasonal growth. Meier said the decline appeared to be
associated with weather conditions that pushed and compacted the thin, mobile
ice near its outer edge.
“Those types of things happen all the
time,” Meier said. “But the magnitude of it certainly is unusual.”
Antarctic sea ice varies more from year
to year than Arctic sea ice because, in contrast to the Arctic, it is not
surrounded by land and can respond more freely to changing wind and weather
conditions. But Antarctic sea ice extent at its annual maximum has generally
been lower in recent years. Because of this large year-to-year variability,
Boisvert and Meier remain cautious about characterizing the change as a
long-term trend.
Scientists have tracked polar sea ice
from space for nearly five decades. During that time, NASA and the National
Oceanic and Atmospheric Administration (NOAA) used a series of satellite
instruments to maintain a continuous sea ice record, beginning with NASA’s Nimbus-7 satellite, which began observations in October 1978. The record
continued with instruments aboard Defense Meteorological Satellite Program satellites beginning in 1987 and NASA’s Aqua satellite from 2002 to 2011. Today, scientists continue the record using data
from the Advanced Microwave Scanning Radiometer 2 (AMSR2), launched in 2012
aboard JAXA’s (Japan Aerospace Exploration Agency) GCOM-W satellite.
Antarctic sea ice typically reaches its annual maximum in late September or early October. NASA and NSIDC will announce the 2026 maximum after scientists confirm that seasonal ice growth has ended.
Media contact: Elizabeth Vlock
NASA Headquarters
James
Riordon
Senior Science Writer
Source: Arctic Sea Ice Reaches 2026 Annual Minimum Extent - NASA Science

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