In the last episode of the Climate Show Gareth drew attention (at 13:40) to two recent papers suggesting that the Weddell Sea area of the West Antarctic Ice Sheet may be more vulnerable to warming than previously realised. One paper, published in Nature Geoscience, recorded that radar mapping has uncovered a deep sub-glacial basin close to the edge of the ice sheet at the head of the Filchner-Ronne ice shelf. The basin measures 100 by 200 km and is well below sea level, nearly 2km deep in places. The ice sheet, currently grounded above the deep basin, may be more unstable than previously thought and could quickly undergo ice loss.
In a related paper, published in Nature, models reveal that the Weddell Sea region may experience warmer ocean conditions at the end of the 21st century, which could provide the trigger for ice sheet change. Professor Martin Siegert of the University of Edinburgh, who led the project, said:
“This is a significant discovery in a region of Antarctica that at present we know little about. The area is on the brink of change, but it is impossible to predict what the impact of this change might be without further work enabling better understanding of how the West Antarctic Ice Sheet behaves.”
I’ve been reading an interesting collection of expert opinion on the second paper, made available by the New Zealand Science Media Centre (SMC) ; it was gathered by the Canadian SMC. The seven experts who commented all thought the paper worthy of respect, and together provided a sense of the breadth and liveliness of scientific interest in the behaviour of the ice shelves. I thought Hot Topic readers might be interested to get the flavour of the comments.
Continue reading “Another Antarctic ice shelf at risk of melt”