Water shortages to be key environmental challenge of the century, Nasa warns

Freshwater supplies have already seriously declined in 19 global hotspots - from China to the Caspian Sea - due to overuse, groundbreaking study shows

Water shortages are likely to be the key environmental challenge of this century, scientists from Nasa have warned, as new data has revealed a drying-out of swaths of the globe between the tropics and the high latitudes, with 19 hotspots where water depletion has been dramatic.

Areas in northern and eastern India, the Middle East, California and Australia are among the hotspots where overuse of water resources has caused a serious decline in the availability of freshwater that is already causing problems. Without strong action by governments to preserve water the situation in these areas is likely to worsen.