On the recent calving of icebergs from the Ross ice shelf

The year 2000 has witnessed the calving of several remarkably large icebergs in the Ross and Weddell seas of Antarctica, including the calving of B-l 5, possibly the largest iceberg yet to be observed. Here we present satellite imagery that records the calving, and precursor events leading up to the detachment of B-l 5 from the Ross Ice Shelf in late March 2000. These images suggest that the evolution of a network of large rifts on the ice shelf over the decade prior to calving has controlled both the time of calving and the giant size of B-15. What controls this evolution in turn remains a mystery.