"Unless something is done to tackle global warming, the Mediterranean will not be the same place that people have enjoyed in the past," said Jennifer Morgan, director of the WWF's climate change programme.

"That paradise will no longer be paradise. It will be hotter, it will have significant agricultural problems and will not be a place people will want to come to on holiday," she told Reuters.

The biggest impact on the weather would be to increase the number of extremely hot days and decrease rainfall in the summer, resulting in increased risk of forest fires, lower crop yields and a drop in tourism, WWF said.

Heatwaves in the region would not just put off tourists from visiting in midsummer, but warmer summers in northern Europe would also reduce the attraction for many holidaymakers of travelling south as they now do.

"We expect that warmer northern European summers would encourage northern Europeans to take domestic holidays," the WWF report said.

Farmers, too, will have to adapt to the warmer climate as in most cases crop yields will be reduced by hotter, drier summers.

The presence of extra carbon dioxide (CO2) in the air will increase certain yields in parts of the region, but this will be more than offset by less rainfall and water for irrigation, the report said.

Global warming is caused by certain gases in the atmosphere trapping the sun's heat. The most important man-made greenhouse gas is CO2 which is a by-product of combustion.

Southern Mediterranean countries have experienced a string of hot summers in recent years, with a heatwave scorching parts of Spain and Italy at the end of last month.

"The models are showing that it's just going to get worse," said Morgan, adding that some regions, such as inland Spain and Turkey, could see average temperatures rise by 5 degrees Celsius in the coming years.

"What we're seeing now is a precursor of stronger impacts in the future. Take today as a warning that we need to act now."