According to new research from the University of Reading in the UK, more than a third of the Antarctic’s ice shelf area could be at risk of collapsing into the sea if global temperatures reach 4°C above pre-industrial levels.
The University of Reading led the most detailed ever study forecasting how vulnerable the vast floating platforms of ice surrounding Antarctica will become to dramatic collapse events caused by melting and runoff, as climate change forces temperatures to rise.
It found that 34% of the area of all Antarctic ice shelves – around half a million square kilometres – including 67% of ice shelf area on the Antarctic Peninsula, would be at risk of destabilisation under 4°C of warming. Limiting temperature rise to 2°C rather than 4°C would halve the area at risk and potentially avoid significant sea level rise.
The researchers also identified Larsen C, the largest remaining ice shelf on the peninsula, which split to form the enormous A68 iceberg in 2017, as one of four ice shelves that would be particularly threatened in a warmer climate.
Dr Ella Gilbert, a research scientist in the University of Reading’s Department of Meteorology, said, “Previous research has given us the bigger picture in terms of predicting Antarctic ice shelf decline, but our new study uses the latest modelling techniques to fill in the finer detail and provide more precise projections. The findings highlight the importance of limiting global temperature increases as set out in the Paris Agreement if we are to avoid the worst consequences of climate change, including sea level rise.”
The new study, published in the Geophysical Research Letters journal, used state-of-the-art, high-resolution regional climate modelling to predict the impact of increased melting and water runoff on ice shelf stability.
Ice shelf vulnerability from this fracturing process was forecast under 1.5°C, 2°C and 4°C global warming scenarios, which are all possible this century. The researchers identified the Larsen C, Shackleton, Pine Island and Wilkins ice shelves as most at-risk under 4°C of warming, due to their geography and the significant runoff predicted in those areas.