February 8, 2010
SW Australian Drought Linked To Antarctic Snowfall
According to scientists on Sunday, a drought that has been ongoing in the southwestern region of Australia for more than 30 years has been linked to higher snowfall in East Antarctica, a phenomenon that may be tied to global warming.
The southwestern drought, where rainfall has declined 15 to 20 percent in recent years, is very unusual when compared to normal activity over the past 750 years, researchers Tas van Ommen and Vin Morgan of the Australian Antarctic Division told AFP.In a report on the issue published online in the journal Nature Geoscience, the researchers remark on the ties to increased snowfall on Antarctica's Law Dome icecap with Australia's drought in the southwest saying it is the result of an apparent "precipitation see-saw."
Cool, dry air flows northwards to southwest Australia, which keeps rainfall amounts down, while warm, moist air flows into East Antarctica, providing abundant snow. This pattern is consistent with previous studies that tied the events to man-made factors that may have played a role in drought.
Other earlier studies also pointed to greenhouse gases that may have changed the Southern Annular Model, a key feature of atmospheric circulation in the southern hemisphere.
Image Caption: Law Dome. Photo: Tas van Ommen
On the Net: