LAKE CHAD, once the fourth-largest body of water in Africa, has shrunk by almost 95 per cent over the past 38 years, according to research sponsored by the US space agency Nasa. Worse, climate change and increasing demands for water have drained the lake to such an extent that it will shortly be nothing more than a “puddle”.

The lake, a precious source of fresh water for at least 20 million people in up to six countries, covers a surface area of 520 square miles – little more than a twentieth of its size in 1963, when it covered 9,650 square miles. The shrinkage is expected to get worse as global warming increases demand for water in the region. The ecosystem of the lake will be wrecked and water supplies to countries such as Chad, Niger, Nigeria and Cameroon, which border the lake’s former shores, and Sudan and Central African Republic, which rely on rivers that form part of its drainage basin, may be threatened.

The Lake Chad basin is a closed water system that depends on monsoon rains to replenish the water that drains from the lake. The lake is also shallow, meaning that its level responds rapidly to changes in rainfall and run-off. Since the early 1960s, the region has experienced a significant decline in rainfall, while the amount of water diverted to irrigate surrounding fields has risen steeply.

Scientists at the University of Wisconsin-Madison and Nasa’s Goddard Space Flight Centre in Maryland, who used pictures from the Nasa Landsat satellite and a new computer model to chart the contraction of the lake, say that the outlook is bleak. Michael Coe, who led the Wisconsin team, said: ‘It will be a puddle. You will get crops and drinking water out of it, but you’ll have no ecosystem left to speak of.”

By Mark Henderson, The Times

Earth Under Fire by Paul LaViolette