Rapid disintegration of the Wordie Ice Shelf in response to atmospheric warming

Abstract

THE breaking up of ice shelves around the Antarctic Peninsula has been cited1 as a “sign that a dangerous warming is beginning in Antarctica”. Here we present satellite images showing the disintegration of the Wordie Ice Shelf, which lies off the west coast of the Antarctic Peninsula (Fig. 1). Fracture, either in the form of surface crevasses or rifts extending to the bottom of the ice shelf, has been responsible for iceberg calving and weakening the central region of the ice shelf. These fracture processes, which led to retreat of the ice front, were apparently enhanced by the presence of increased amounts of melt water, resulting from a warming trend recorded in mean annual air temperatures in Marguerite Bay. If this warming trend continues, other nearby ice shelves on the Antarctic Peninsula may be at risk. But substantial additional warming would be required before similar processes could initiate breakup of the Ross and Filchner–Ronne ice shelves, which help stabilize the West Antarctic ice sheet.