Asian Water Problems

Science magazine reports new results on the ground water resources in North India:

Satellite remote sensing of a 2000-kilometer swath running from eastern Pakistan across northern India and into Bangladesh has for the first time put a solid number on how quickly the region is depleting its groundwater. The number "is big," says hydrologist James Famiglietti of the University of California, Irvine—big as in 54 cubic kilometers of groundwater lost per year from the world's most intensively irrigated region hosting 600 million people. "I don't think anybody knew how quickly it was being depleted over that large an area," Famiglietti says.

Satellite-derived Climatic Moisture Index map of China. The Climatic Moisture Index equals rainfall divided by potential evapotranspiration. Desertification indices of this type can be generated using low-resolution remote sensing data in an Energy aand Water Balance Monitoring System. The example provided shows desertification indices for the whole of China: desertification is one of the subjects of the joint ESA-China Dragon Program. (Image courtesy European Space Agency) Click here for image source.

Sean Gallaghar writes recently from the Pulitzer Center:

It is estimated that 20% of China's land area, some 1.74 million square kilometers, is now classified as desert. Affecting the lives of an estimated 400 million people, it is the most important environmental issue in China today.

A decade ago, Ron Gluckman wrote:

Few people think of China as a desert nation, yet it is among the world's largest. More than 27%, or 2.5 million square kilometers, of the country comprises useless sand (just 7% of Chinese land feeds about a quarter of the world's population). A Ministry of Science and Technology task force says desertification costs China about $2-3 billion annually, while 800 km of railway and thousands of kilometers of roads are blocked by sedimentation. An estimated 110 million people suffer firsthand from the impacts of desertification and, by official reports, another 2,500 sq km turns to desert each year.

Comment: I take the differences among these scattered reports to suggest that there is a dearth of accurate scientific information. However, the information that is available indicates a huge problem, rapidly growing worse.

Lets hope UNESCO's water program can help mobilize a global scientific community to study the problems of Asian water supply, at least to get an adequate description of the magnitude and urgency of the problems. JAD