Winter sea ice cover in the Arctic was the lowest it's ever been at its annual peak on March 22, 2025, according to NASA and the National Snow and Ice Data Center (NSIDC) at the University of Colorado, Boulder. At 5.53 million square miles (14.33 million square kilometers), the maximum extent fell below the prior low of 5.56 million square miles (14.41 million square kilometers) in 2017.
Ice cover ebbs and flows through the seasons in the Arctic (left) and the Antarctic (right). Overall, ice cover has declined since scientists started tracking it half a century ago. Download this visualization from NASA's Scientific Visualization Studio: https://svs.gsfc.nasa.gov/5099 Trent Schindler/NASA's Scientific Visualization Studio In the dark and cold of winter, sea ice forms and spreads across Arctic seas. But in recent years, less new ice has been forming, and less multi-year ice has accumulated. This winter continued a downward trend scientists have observed over the past several decades. This year's peak ice cover was 510,000 square miles (1.32 million square kilometers) below the average levels between 1981 and 2010. In 2025, summer ice in the Antarctic retreated to 764,000 square miles (1.98 million square kilometers) on March 1, tying for the second lowest minimum extent ever recorded. That's 30% below the 1.10 million square miles (2.84 million square kilometers) that was typical in the Antarctic prior to 2010. Sea ice extent is defined as the total area of…