Dust from Patagonia Linked to Antarctic Climate
30.03.2009 - Atmosphere & Space, Land & Geology, Ice & Snow, Other, Antarctic
The movement of glaciers in Argentina and Chile is particularlyinteresting for scientists hoping to understand how the global climatehas changed during the past ice age, in order to help them predictenvironmental changes in the future. A new study by scientists from theUniversities of Edinburgh, Stirling and Lille, published in NatureGeoscience, shows that the ebb and flow of these glaciers has had aninfluence on the dust blown south to Antarctica from the windy plainsof Patagonia, which has been deposited on the ice periodically duringthe past 80,000 years.
The study has proven that the "dustiest" periods for Antarctica were also the coldest for Patagonia. During these periods, glaciers in Patagonia were at their biggest and released their melt water, which contained dust particles, onto barren windy plains, from where dust was blown over to Antarctica. Thus, when the glaciers retreated even slightly, their melt water ran into lakes at the edge of the ice, which trapped the dust, so that fewer particles could be blown across the ocean to Antarctica.
"Ice cores from the Antarctic ice sheet act as a record of global environment," said Professor David Sugden, of the University of Edinburgh. However, the dust levels showed some sudden changes which had us puzzled - until we realised that the Patagonian glaciers were acting as an on/off switch for releasing dust into the atmosphere."
