More And More Deserts On Earth
The world is turning to dust, with lands the size of Rhode 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 percent of Spain is threatened, while China has lost 36,000 square miles to desert — an area the size of Indiana — since the 1950s.
This week the United Nations marks the 10th anniversary of the Convention to Combat Desertification, a plan aimed at stopping the phenomenon. Despite the efforts, the trend seems to be picking up speed — doubling its pace since the 1970s.
"It's a creeping catastrophe," said Michel Smitall, a spokesman for the U.N. secretariat that oversees the 1994 accord. "Entire parts of the world might become uninhabitable."
Slash-and-burn agriculture, sloppy conservation, overtaxed water supplies and soaring populations are mostly to blame. But global warming is taking its toll, too.
The United Nations is holding a ceremony in Bonn, Germany, on Thursday to mark World Day to Combat Desertification, and will hold a meeting in Brazil this month to take stock of the problem.
The warning comes as the movie,
, sparks renewed interest in the debate over climate change, and as rivers and lakes dry up in the American West, giving Americans a taste of what's to come elsewhere.The United Nations says:
Most at risk are dry regions on the edges of deserts - places like sub-Saharan Africa or the Gobi Desert in China, where people are already struggling to eke out a living from the land.
As populations expand, those regions have become more stressed. Trees are cut for firewood, grasslands are overgrazed, fields are over-farmed and lose their nutrients, water becomes scarcer and dirtier.
Technology can make the problem worse. In parts of Australia, irrigation systems are pumping up salty water and slowly poisoning farms.
In Spain, Portugal, Italy and Greece, coastal resorts are swallowing up water that once moistened the wilderness. Many farmers in those countries still flood their fields instead of using more miserly "drip irrigation," and the resulting shortages are slowly baking the life out of the land.
The result is a patchy "rash" of dead areas, rather than an easy-to-see expansion of existing deserts, scientists say. These areas have their good times and bad times as the weather changes. But in general, they are getting bigger and worse-off.
The trend is speeding up, but it has been going on for centuries, scientists say. Fossilized pollen and seeds, along with ancient tools like grinding stones, show that much of the Middle East, the Mediterranean and North Africa were once green. The Sahara itself was a savanna, and rock paintings show giraffes, elephants and cows once lived there.
Global warming contributes to the problem, making many dry areas drier, scientists say. In the last century, average temperatures have risen over 1 degree Fahrenheit worldwide, according to the U.S. Global Change Research Program.
By Chris Hawley