More than a third of the vast floating ice platforms surrounding Antarctica could be at risk of collapsing and releasing “unimaginable amounts” of water into the sea if global temperatures reach 4 ° C above pre-industrial levels, UK scientists say.
Researchers at the University of Reading said limiting the temperature rise to 2 ° C could halve the risk area and prevent a drastic rise in sea level.
The findings, published in the journal Geophysical Research Letters, suggest that 4C warming could leave 34% of the area of all Antarctic ice shelves – totaling about half a million square kilometers – at risk of collapse.
Ice shelves are permanent floating ice sheets that connect to a land mass; most surround the coasts of Antarctica.
Ella Gilbert, a research scientist in the meteorology department at the University of Reading, said: “Ice shelves are important buffers, preventing glaciers on land from flowing freely into the ocean and contributing to rising sea levels. When they collapse, it is like a giant cork being removed from a bottle, allowing unimaginable amounts of water from the glaciers to be poured into the sea.
“We know that when melted ice accumulates on the surface of ice platforms, it can cause them to break and collapse in a spectacular way.
“Previous research has given us an overview in terms of predicting the decline of the Antarctic ice shelf. But our new study uses the latest modeling techniques to fill in the finer details and provide more accurate projections. “
Gilbert said the team’s work highlighted the importance of limiting increases in global temperature as set out in the Paris climate agreement, which promotes a global framework to prevent dangerous climate change by limiting global warming to less than 2 ° C above pre-industrial levels. .
As part of their modeling study, the researchers also identified Larsen C, the largest remaining ice shelf on the peninsula, as being particularly at risk in a warmer climate. They said other ice rigs facing this threat include Shackleton, Pine Island and Wilkins.
Gilbert said: “If temperatures continue to rise at current rates, we could lose more Antarctic ice shelves in the coming decades. Limiting warming will not only be good for Antarctica – preserving the ice shelves means less global sea level rise, and that is good for all of us. “