Is Australia the world's driest continent?

My father, who as a Kiwi, used to tease Australians sometimes that one third of Australia was desert, one third semi arid, and the other third not much use anyway! Certainly Australia is a dry continent, but is it the driest?

Looking at The Weather Doctor, I see that Antarctica is the driest continent, but it is not inhabited outside research teams and support.

If we look just at South America, we can eliminate Europe and South America from the possibilities although South America has the driest area on Earth, outside the polar continent, located in Chile. North America could have a strong argument in the northern regions, but the southern areas such as Central America are quite wet. That leaves the A continents: Australia, Africa and Asia.

Looking at the climate classification maps, Australia seems to have the highest percentage of dry climates. But the Sahara is larger in area than all of Australia. And the dry interior of Asia along with the Middle East and dry areas of China and India give Asia large dry regions.

Still, if we look at overall patterns, The Encyclopedia of Climatology gives the following facts about Australia:

• 50% of land receives less than 300 mm/year of precipitation
• 80% receives less than 600 mm/yr
• Over 75%, the potential evaporation is greater than 2500 mm/yr
• In central Australia the evaporation potential is around 4500 mm/yr, 20 times the actual annual rainfall.

This leads The Weather Doctor to conclude that Australia can fairly claim to be the world's driest inhabited continent in an overall sense.