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BOB HIRSHON (host):
Shrinking rivers. I’m Bob Hirshon and this is Science Update.
Many of the world’s big rivers are drying out, with no sign of relief. Kevin Trenberth of the National Center for Atmospheric Research and his colleagues analyzed 925 rivers around the globe, from 1948 to 2004. Trenberth says a third of these rivers showed significant changes in annual flow into the ocean. And the majority of those that changed have gotten drier.
KEVIN TRENBERTH (National Center for Atmospheric Research):
There are two major factors that are affecting the river flows. One of them is climate change. But another one is also human use of water.
HIRSHON:
… Uses that include irrigation, plumbing and drinking water, which increase as populations grow and nations industrialize. The findings suggest that many regions will need to somehow meet rising demand with dwindling supply. I’m Bob Hirshon for AAAS, the Science Society.