Antarctica and the Arctic are two very different environments: the former is a continent surrounded by ocean, the latter is ocean enclosed by land. As a result, sea ice behaves very differently in the two regions. While the Antarctic sea ice yearly wintertime maximum extent hit record highs from 2012 to 2014 before returning to average levels in 2015, both the Arctic wintertime maximum and its summer minimum extent have been in a sharp decline for the past decades. Studies show that globally, the decreases in Arctic sea ice far exceed the increases in Antarctic sea ice.