Just a current theory, but interesting nonetheless.
"The results, which were published in the Nature Geoscience journal, suggest that sea ice and regional wind patterns had a vital role to play in stabilising the ice shelf.
A change in wind conditions over the Weddell Sea pushed floating sea ice against the ice shelves, binding them together.
Before 2002, winds in the same area blew sea ice away from the coast, wearing down what scientists call a “buttressing effect.” This meant ice shelves were exposed to ocean waves and currents, leading to the formation - or calving - of icebergs that broke away into the sea."
