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
