Global Warming

Global warming endangers South American water supply

Chile and Argentina may face critical water storage issues due to rain-bearing westerly winds over South America's Patagonian Ice-Field to moving south as a result of global warming.

A reconstruction of past changes in the North and Central Patagonian Ice-field, which plays a vital role in the hydrology of the region, has revealed the ice field had suddenly contracted around 15,000 years ago after a southerly migration of westerly winds.

This migration of westerly winds towards the south pole has been observed again in modern times and is expected to continue under a warming climate, likely leading to further ice declines in this area affecting seasonal water storage.

"We found that precipitation brought to this region by Southern Hemisphere westerlies played an important role in the glaciation of the North Patagonian Ice-Fields," said Dr Chris Fogwill from the Climate Change Research Centre at the University of New South Wales. 

"Our research has shown this ice-field significantly reduced in size when those winds moved southwards."

The North Patagonian Ice-field is vital to maintain seasonal water storage capacity for Argentina and Chile.

"Worryingly, this study suggests the region may well be on a trajectory of irreversible change, which will have profound impacts on agriculture and the increasing dependency on hydroelectric power in Chile and Argentina," Dr Fogwill said.