Planet drying up: U.N.

The world is turning to dust, with lands about half the size of Prince Edward Island becoming desert wasteland every year and the problem threatening to send millions of people fleeing to greener countries, the United Nations says. One-third of the Earth's surface is at risk, driving people into cities and destroying agriculture in vast swaths of Africa. Thirty-one per cent of Spain is threatened, while China has lost 93,000 square kilometers to desert - an area the size of Indiana - since the 1950s. By 2025, two-thirds of arable land in Africa will disappear, along with one-third of Asia's and one-fifth of South America's. Some 135 million people - equivalent to the populations of France and Germany combined - are at risk of being displaced.