Tuesday, 2 October 2012

Lake Chad, almost gone


Lake Chad has been a source of freshwater for irrigation projects in Chad, Niger and Cameroon. There is a malnutrition crisis in the region around Lake Chad, which has been shrinking in size for decades as water levels recede.




Satellite maps show a dramatic decrease in the size of the lake over the past 30 years.



Since 1963, the lake has shrunk to nearly a twentieth of its original size, due both to climatic changes and to high demands for agricultural water. Since 1963, the surface area of Lake Chad has decreased from approximately 25,000 km2 to 1,350 km2 (Scientific American, 2001).

YEAR
SURFACE AREA OF LAKE CHAD
1966
22,772 km2
1973
15,400 km2
1982
2,276 km2
1994
1,756 km2


Between 1953 and 1979, irrigation had only a modest impact on the Lake Chad ecosystem. But between 1983 and 1994 irrigation had increased four-fold.

About 50% of the decrease in the lake’s size since the 1960s. Research carried out over the past 40 years indicates that the main factors in the shrinking of the lake have been:
  • Major overgrazing in the region, resulting in a loss of vegetation and serious deforestation, contributing to a drier climate.

  • Large and unsustainable irrigation projects built by Niger, Nigeria, Cameroon and Chad, which have diverted water from both the lake and the Chari and Logone rivers.