After growing through the fall and winter, sea ice in the Arctic appears to have reached its annual maximum extent. The image above shows the ice extent—defined as the total area in which the ice concentration is at least 15 percent—at its 2023 maximum, which occurred on March 6. On this day the extent of the Arctic sea ice cover peaked at 14.62 million square kilometers (5.64 million square miles), making it the fifth lowest yearly maximum extent on record. This year’s maximum is 1.03 million s