The world's fresh water supplies are almost fully exploited.Almost al, 97 per cent, of the world's water is salt. Of the fresh water in the world, two thirds is locked up as ice and snow (the cryosphere - to you and me, kid!). Globally, three quarters of the water that is used is used by agriculture. India, China and the United States, use more fresh water than is available. The water level in those nation's aquifers is falling as a result.

The current food crisis has come about largely as a result as the shortfall in available water begins to impact on the cost of irrigation.