Dwindling ice at the top of the world threatens Arctic species (SN Online: 5/14/08), can spread pollution (SN: 1/23/16, p. 9) and could open the region to transpolar shipping. In 2012, Arctic sea ice hit a record low since satellite observations began: just 3.39 million square kilometers, far below the average of 6.22 million square kilometers set from 1981 through 2010. How quickly the ice will continue to disappear remains unclear.