The Big Dry, a prolonged drought that affected southeast Australia from 1997 to 2011, was more extensive than previously thought.

Gavan McGrath at the University of Western Australia in Crawley and his colleagues analysed satellite data from across the continent and found evidence of decreased water storage, rainfall and plant growth throughout the country between 2002 and 2010. In the southeast, the drought correlated with an irregular Indian Ocean circulation, whereas in the northwest it was associated with a decreased frequency of tropical cyclones. The authors say that the northwest drought coincided with and probably exacerbated the one in the southeast.

The findings suggest that distinct climatic factors such as decadal cyclone trends and changes in ocean circulation can combine to create a continental-scale drought.


Geophys. Res. Lett. (2012)