Australian Shield

The Australian Shield (or Western Plateau) is Australia's largest drainage division.

It is mainly the old rock shield of Gondwana. It covers two thirds of the continent: 2,700,000 square kilometres of dry land including large parts of Western Australia, South Australia, and the Northern Territory. For comparison, it is roughly the same size as the whole of continental Europe from Poland to Portugal. 

Rain rarely falls in this region. Apart from a handful of permanent waterholes, surface water is absent at all times except after heavy rain. Most of the territory is flat sandy or stony desert with a sparse covering of shrubs or tussock grasses. Average rainfall varies from one area to another. It has 100 to 350 mm of rainfall per year (between four and 14 inches).

There are no permanent watercourses. The general trend is for run-off to flow inland, but there is not enough rainfall to make any marked drainage pattern. There is a total inflow to Australia's water resources of 292 BCM (billion cubic metres). Two water management areas (the Great Artesian Basin and the Mereenie Sandstone – Alice Springs) used more water than the total annual inflow.

According to the Prime Minister's office, as the effects of climate change intensifies, Australia faces increasingly acute long-term water shortages with lower rainfall, rivers drying up and dam water levels falling. 

Related pages
 Great Victoria Desert

 References 

Category:Geography of Australia
Category:Regions of Australia
Category:Water