Nature - Antarctic Ice Shelves More Vulnerable To Rapid Collapse Than Previously Thought
Most of Antarctica’s vital ice shelves that encircle the continent remain frozen all year round and are stable, but fractures in their surfaces could make them vulnerable to rapid collapse if rising temperatures drive meltwater into the gaps, according to a new study.
The ice shelves, which float on the ocean at the edge of the continent, are a crucial barrier to glaciers moving from the land to the sea, and their sudden failure could therefore have “huge implications for sea level”, an international research team said in the paper, which was published in the journal Nature.
Many ice shelves form in the protected waters of the continent’s numerous expansive bays and gulfs. Here, the land on either side compresses the ice; this pressure helps maintain the ice shelves and braces them against the slow march of the glaciers where they meet the frozen seas. But large fractures regularly appear as the ice nears the open ocean. The land on either side drops away and the ice shelves are free to stretch out.
Satellite observations show that as a result of this freedom, the shelves rip apart. Most of them are raked with numerous long fractures perpendicular to the direction of stretching. Fractures that form at the surface can be tens of metres deep. Others, forming from the bottom, can penetrate hundreds of meters upwards in the ice. Some of these fractures are hundreds of metres wide. It is these large cracks, combined with warming temperatures that have raised concerns about the continued stability of the ice shelves.
EDIT
https://www.independent.co.uk/environment/climate-crisis-antarctica-ice-shelves-cracks-hydrofracturing-glaciers-a9690111.html
