Summary

Nearly five decades of satellite observations reveal a troubling transformation in the Arctic, where sea ice is shrinking in both summer and winter, and much of the remaining ice is becoming younger and thinner. The Arctic Ocean is covered by a vast expanse of frozen seawater that expands and contracts with the seasons. Ice typically builds up throughout the long, dark winter, reaching its greatest extent in March before retreating during the warmer months to a September minimum.

AI summaries can be wrong sometimes—always verify important details using the source article.