As illustrated by recent events, global warming is causing major climate impacts at the earth’s poles.
In March 2008, a section of the Wilkins Ice Shelf four times the size of Washington, DC, collapsed in the southwestern Antarctic Peninsula. Ice shelves are large platforms of thick, ancient sea ice that float on the ocean. They are formed by snow and freezing meltwater.
The collapse of the Wilkins Ice Shelf follows the loss of the much larger Larsen B Ice Shelf in 2002. Scientists attribute both of these events to global warming.
In April, scientists reported that the Arctic’s largest ice shelf had split in three after discovering cracks 11 miles long by 131 feet wide in the 3,000-year-old Ward Hunt Ice Shelf. Cracks in the ice shelf, which was found to have split in two six years ago, are permanent and make it more vulnerable to disintegration as Arctic temperatures rise.
The Ward Hunt Ice Shelf is located in the Arctic Circle off the northwestern coast of Canada’s Ellesmere Island. Arctic researchers report that Ellesmere’s coastline was completely surrounded by a single ice shelf that broke into multiple shelves about 100 years ago. The Ward Hunt Ice Shelf is one of five remaining Canadian ice shelves.
Scientists are concerned that despite a cold winter in certain areas, Arctic sea ice cover is much thinner than in the past and therefore more vulnerable to summer melting. The Arctic ice cap declined to a record minimum size in summer 2007, and the consensus among climate scientists is that the fast pace of decline in the Arctic sea ice cover is attributable to human-induced global warming.
This page includes links to information that helps explain the climate impacts being observed in the Antarctic and Arctic.