Man-caused climatic changes pose a major problem for all nations, but reversing them could be just as bad, an Environmental Protection Agency official said Friday.

"There is evidence man is causing profound change in the Earth's environment, and there will be consequences for some time," said Peter Beedlow of the Environmental Research Laboratory, Corvallis, Ore., and leader of the EPA's global climate research team.But, Beedlow said, if research and cleanup policies "are directed at the wrong thing, the impact on the future could be as great as that resulting from what is presently happening."

One problem, he said, is climatic shifts brought about by the global warming. That can have "negative effects" on one part of the Earth, but "possibly produce beneficial effects for another area, country or continent."

And it will be difficult to immediately resolve such problems because the effects will last for several decades, he said, "so it's difficult now to get people to buy into suggested policies."

Climate change is an international problem, Beedlow said, and "to enforce our policies on other countries, we will have to demonstrate the adverse effects in those countries."

Beedlow told natural resource managers, faculty and students at Utah State University's college of natural resources symposium on climate change "there is a need for researchers to understand more completely" what has happened and how much man is to blame.

"We need to know how the environment changed in the past and we need documentation of Earth history, particularly since the glacial period," he said. "There are complexities which also will involve scientists, lawyers and social scientists."