December 13, 2013

Very little old sea ice remains in the Arctic

All seven of the smallest September (summer minimum) ice extents in the satellite record have occurred in the last seven years, part of the evidence of the decades-long trend in Arctic warming. But surface area isn’t the only quality of the ice that is changing. Wind and ocean circulation patterns are conspiring with a warmer climate to reduce the amount of year-round (multi-year) ice, transforming the remaining ice into a younger, thinner version of its old self.