A record low for early October
Antarctic sea ice has fallen to a record low for this point in the year. Sea ice extent was 16.73 million square kilometres on October 1, 2026, the lowest for that date in the satellite record. On October 5, the ice area was 1.77 million square kilometres below the 1981 to 2010 average, the largest negative anomaly recorded for the day.
What scientists watch
Antarctic sea ice usually reaches its yearly maximum in late September or early October. NASA and the National Snow and Ice Data Center will confirm the 2026 maximum once scientists are certain that seasonal growth has ended. Satellites have tracked polar sea ice for nearly five decades, starting with NASA's Nimbus-7 in 1978.
The northern picture
In the Arctic, sea ice reached its 2026 annual minimum last month, continuing a long decline. Research published this year found that wind-driven upwelling helped pull warmer water from the deep ocean toward the surface around Antarctica. That process ended a period when sea ice had grown for decades and helped drive the sharp drop seen since 2016.
Scientists say the two poles do not behave the same way, and Antarctic trends show more year-to-year variation than the Arctic. Even so, several recent seasons have set new records. Sea ice loss affects ocean circulation, wildlife such as penguins and krill, and the bright surface that reflects sunlight and helps keep the planet cool. Researchers continue to watch whether the recent lows mark a lasting shift or a run of unusual years.