In January 1995, 4200 square kilometers of the northern Larsen Ice She
lf, Antarctic Peninsula, broke away. Radar images from the ERS-1 satel
lite, complemented by field observations, showed that the two northern
most sections of the ice shelf fractured and disintegrated almost comp
letely within a few days. This breakup followed a period of steady ret
reat that coincided with a regional trend of atmospheric warming. The
observations imply that after an ice shelf retreats beyond a critical
limit, it may collapse rapidly as a result of perturbated mass balance
.