Civilization Drying Up Earth's Major Rivers

"Some of the developing world's largest rivers are drying up because of climate change, threatening water supplies in some of the most populous places on Earth, say scientists.

Researchers from the US-based National Center for Atmospheric Research (NCAR) analysed data combined with computer models to assess flow in 925 rivers — nearly three quarters of the world's running water supply — between 1948 and 2004.

A third of these had registered a change in flow and most of them — including the Niger in West Africa, the Ganges in South Asia and the Yellow River in China — were dryer.

"Reduced run-off is increasing the pressure on freshwater resources in much of the world, especially with more demand for water as population increases. Freshwater being a vital resource, the downward trends are a great concern," said Aiguo Dai, a scientist at NCAR and lead author of the research.

Rivers are losing water for a variety of possible reasons, say the researchers, including the installation of dams and the use of water for agriculture. But in many cases the decrease in flow is because of climate change, which is altering rainfall patterns and increasing evaporation because of higher temperatures."

ORIGINAL SOURCE: SciDev.Net