From San Francisco, at a meeting of the American Geophysical Union
Early this year, most of Antarctica's Larsen B ice shelf fell apart during the region's warmest summer on record (SN: 3/30/02, p. 197: Available to subscribers at All Cracked Up from the Heat? Major hunk of an Antarctic ice shelf shatters and drifts away). Now, scientists think they know what accelerated that rapid disintegration.
In just 5 weeks, a 3,200-square-kilometer, Rhode Island–size section of the ice shelf collapsed and spread into a 6,750-square-kilometer mélange of icebergs, says Douglas R. MacAyeal of the University of Chicago. However, only about 1,600 square kilometers of that area appeared white and covered with snow, as the ice shelf had. The rest of the exposed ice was riddled with rocks and showed the distinct blue color of ice that's been compressed in glaciers. On satellite images, the sea "looked like a big blue Slurpee," says MacAyeal.