Climate change 'to end summer rain'

We may never see summer rain again if global warming takes hold, new research claims.

Previous studies have shown summers becoming hotter and wetter. But experts believe they have overlooked pollution.

Computer simulations of cities suffering from increased temperatures revealed that air pollutants formed large clouds that delayed rainfall.

Earlier theories have assumed that rising temperatures-would mean more evaporation and therefore more rain.

But Beate Liepert, of New York's Lamont-Doherty Earth Observatory, said increased airborne pollutants would trap water vapour in the atmosphere for about half a day longer than normal and so reduce rainfall frequency.