Previously thought to be barely affected by the formation of meltwater ponds, new research has shown East Antarctica experienced large numbers of supraglacial lakes developing during the summer months of every year between 2000 and 2013. Jim Drury reports.
This new NASA animation shows Arctic sea ice cover reach its second lowest recorded level this summer. The situation in Antarctica offers cause for concern as well. For the first time meltwater ponds have been seen evolving on the surface of an East Antarctic coastal glacier. British researchers used satellite observations to spot more than 100 ponds and rivers forming during the summer months from 2000 to 2013. SOUNDBITE (English) STUDY CO-AUTHOR DR AMBER LEESON, OF LANCASTER UNIVERSITY, SAYING: "What was surprising about it was the extent of the supraglacial lake coverage that we found. We really weren't expecting to find lakes as far inland as 20 kilometres, which was the furthest inland lake we found during the study." For a short period each summer, air temperatures rose above zero, allowing melting to occur. With warmer East Antarctic summers expected more meltwater ponds are predicted. SOUNDBITE (English) STUDY CO-AUTHOR DR AMBER LEESON, OF LANCASTER UNIVERSITY, SAYING: "If they form on the grounded ice, which is the bit of the ice sheet that sits on the bedrock then the water they contain can drain away through the ice to the base, where it can lubricate the flow of the ice and make it flow a bit faster. If they form on the floating part of the ice, which is where the ice shelf extends over the ocean and begins to float on the sea, by repeatedly filling and draining they can actually weaken the ice shelf." Such weakening could cause ice shelves to collapse, contributing to rising global sea levels. The team insists that East Antarctica is one of the world's more stable ice sheets. But its newly-shown vulnerability to climate change is bound to worry polar scientists and environmentalists.
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