France would feel the heat the most, said the report released Friday by Purdue University's Climate Change Research Center.
"Rare events today, like the 2003 heat wave in Europe, will become much more common as greenhouse gas concentrations increase," said researcher Noah Diffenbaugh, who led the study.
If greenhouse gas emissions continue to rise that the current project rates, the number of dangerously hot days would increase by 200 percent to 500 percent in the Mediterranean, Diffenbaugh said.
"Technological and behavioral changes that are made now will have a big influence on what actually happens in the future," Diffenbaugh said.
The researchers used a supercomputer in the National Climate Center in Beijing to run the climate model of the 21 countries in the Mediterranean region.