Even when the Arctic goes dark and cold, thinning ice could keep the North Pole from cooling off.
The loss of insulating ice between the ocean and atmosphere increases the amount of heat-trapping water vapor and clouds in the Arctic air. That extra moisture keeps air temperatures relatively warm during fall and winter and melts even more ice, new climate simulations suggest. This self-reinforcing cycle could partially explain why Arctic warming has outpaced the global average over recent decades, researchers report online November 11 in the Journal of Climate.