Indigenous peoples in the Arctic say global warming is a threat to their culture because it melts the ice on which their hunts of seals and polar bears depend. Other scientific models indicate southern Europe may get drier.
"I do see even within the confines of Europe, from the Mediterranean to the Arctic, there is enough momentum to consider we will have climate-change refugees," said Jacqueline McGlade, executive director of the EEA, an arm of the European Union.
"The difficulties are going to be when the northern people are moving away because permafrost (hard-frozen ground) is melting and southern people are moving up because of drought. They [are] all going to end up in the middle," she told a news conference.
The panel of scientists that advises the United Nations, projects world temperatures are likely to rise by 1.4 to 5.8 centigrade by 2100, triggering more frequent floods, droughts and melting icecaps, and driving thousands of species to extinction.
Many scientists say emissions of heat-trapping carbon dioxide from cars, power plants and factories are mainly to blame for blanketing the planet and nudging up temperatures. Others say models are unreliable and exaggerate the effects.
Ms. McGlade said a warming climate might eventually discourage people from living or retiring near the Mediterranean.
"If in the next 20 to 30 years those conditions around the Mediterranean are going to move toward an extreme, with drought and lack of water, will people then retire to such countries?" she asked. She also said people already living in those areas will then want to migrate northward when that starts to happen.
A report last year by 250 experts said climate change is happening fastest in the Arctic, partly because dark soil or water, once exposed, soaks up far more heat than snow or ice.