Washington, March 30 (ANI): In a new study, dust trapped deep in Antarctic ice sheets is helping scientists unravel details of past climate change.
The study, carried out by the Universities of Edinburgh, Stirling and Lille, has found that the very coldest periods of the last ice age correspond with the dustiest periods in Antarctica's past, thus establishing a link between the two.
They found that dust blown south to Antarctica from the windy plains of Patagonia - and deposited in the ice periodically over 80,000 years - provides vital information about glacier activity.
It indicates that the ebb and flow of glaciers in the Chilean and Argentinian region is a rich source of information about past climates - which had not until now been fully appreciated by scientists.
During the last ice age, glaciers in Patagonia were at their biggest and released their meltwater, containing dust particles, on to barren windy plains, from where dust was blown to Antarctica.
When the glaciers retreated even slightly, their meltwater ran into lakes at the edge of the ice, which trapped the dust, so that fewer particles were blown across the ocean to Antarctica.
Dust from the ice cores was analysed and found to be a close match with mud of the same age in the Magellan Straits, showing that most of the dust originated in this region.
According to Professor David Sugden, of the University of Edinburgh, "Ice cores from the Antarctic ice sheet act as a record of global environment. 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." (ANI)