Scientists studied dust from the ice cores of glaciers
Ancient dust buried deep in Antarctic ice sheets could hold information about climate change, a study has suggested.
Research by Edinburgh, Stirling and Lille universities indicated that Patagonian glaciers were acting as an "on/off switch" for releasing dust.
Researchers said during the coldest periods of the last ice age, these glaciers were at their biggest and dust from them was blown to Antarctica.
During warmer periods, dust was trapped in meltwater which ran into lakes.
The study concluded that the coldest periods of the past 80,000 years corresponded with the dustiest periods in Antarctica's past.
Dust from the ice cores was analysed and scientists said they were a close match with mud of the same age in the Magellan Straits, suggesting that most of the dust originated in this region.
Scientists hope the findings will improve understanding of global climate change during the past ice age, and also help predict environmental changes in the future.
Prof David Sugden, of the University of Edinburgh, said: "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."
The study was supported by the Natural Environment Research Council. The findings were published in Nature Geoscience.