A team of British and American researchers, co-led by the University of Cambridge, has measured how much the McMurdo ice shelf in Antarctica flexes in response to the filling and draining of meltwater lakes on its surface.
A team of British and American researchers, co-led by the University of Cambridge, has measured how much the McMurdo ice shelf in Antarctica flexes in response to the filling and draining of meltwater lakes on its surface. This type of flexing had been hypothesised before and simulated by computer models, but this is the first time the phenomenon has been measured in the field. The results are reported in the journal Nature Communications.
The results demonstrate a link between surface melting and the weakening of Antarctic ice shelves and support the idea that recent ice shelf breakup around the Antarctic Peninsula may have been triggered, at least in part, by large amounts of surface meltwater produced in response to atmospheric warming.
As the climate continues to warm, more and more ice shelves may become susceptible to flex, fracture and break up over the coming century.
Most of the Antarctic continent is covered by the Antarctic Ice Sheet, which is up to four kilometres thick and contains enough ice to raise global sea levels by about 58 metres. Over most of the continent and for most of the year, air temperatures are well below zero and the ice surface remains frozen. But around 75% of the ice sheet is fringed by floating ice shelves, which are up to a kilometre thick, mostly below sea level, but with tens of metres of their total height protruding above the water. In the summer months, when air temperatures rise above freezing, the surfaces of these ice shelves are susceptible to melting.
Read more at University of Cambridge
Image: Surface lakes on ice sheet. CREDIT: Alison Banwell
