The Broads are only one area under threat, the study says.

The study, by the Tyndall Centre for Climate Change Research at the University of East Anglia, predicts more rainfall in winter and less in summer due to greenhouse gases from carbon dioxide emissions.

The Broads are predicted to be 3.6C degrees hotter in the summer months 80 years from now.

The changes would be expected to lead to more flooding in the winter and spring and poor summer water quality which could affect habitats.

The study claims that if carbon dioxide concentrations could be kept down, the climate changes would not pose a problem to the Broads and other bodies of water worldwide.

Lake Constance in Germany is expected to rise by 4.6C, and Lake Tengis in Kazakhstan by 5.7C in the winter.

Professor Kerry Turner, Chairman of the Broads Authority, said: "If these carbon reduction targets are to be met, it is vital that all energy users, from multinational corporations to individual households, recognise the urgent need to be much more efficient in their use of energy."

Delegates from 30 nations are to hear the report, presented by its author, Mike Hulme of the Tyndall Centre, on Friday.

The delegates are in Norwich to attend the Living Lakes Conference.