President-elect Bush was urged Thursday to support development of new types of nuclear power plants as a way of slowing global warming caused by the "greenhouse effect."

Research on new types of nuclear reactors could lead to energy sources that produce no carbon dioxide, a principal cause of the atmospheric warming, said a panel convened by the National Academy of Sciences and two sister organizations.The academy, the National Academy of Engineering and the National Institute of Medicine made a series of recommendations to the president-elect on the environment, AIDS, space and science policy.

In a cover letter to Bush, the presidents of the three bodies said, "global environmental change must be made more prominent in the scientific, political and foreign policy agendas of the United States."

The letter concentrated on five other points:

-Since global warming and acid rain are both produced by use of fossil fuels, "efforts to enhance both energy efficiency and conservation should be strengthened." It added that ways to increase "use of the `cleanest' fossil fuels, such as natural gas, should be considered, but in the context of their finite availability."

-Immediate assessment of possible responses to rising sea levels, drought and the northward migration of agricultural zones.

-Nations that have signed a treaty to reduce emissions that destroy the ozone layer should be encouraged to accelerate those reductions and aim at a "total phaseout." These chemicals account for about a fifth of the expected global warming. The Environmental Protection Agency already has called for such a phaseout.

-Strategies are needed to prevent the destruction of tropical forests. The loss of forests around the world probably adds a fifth of the carbon dioxide produced by fossil fuels, the group said. An area the size of Missouri is lost each year, according to some estimates, and if nothing is done there could be no tropical forests left early in the next century, the panel said.