A National Academy of Sciences panel that considered everything from ordinary energy savings to blocking out sunlight by firing dust particles into space has concluded there is no single, simple answer to the threat of global warming from the greenhouse effect.
The report said some proposals could be very expensive and would have uncertain results, while others could save both money and the environment.In its "Policy Implications of Greenhouse Warming - Report of the Mitigation Panel," the committee examined dozens of measures the nation could take to reduce the amount of carbon dioxide and other gases set loose in the atmosphere. These gases theoretically trap the sun's heat near the Earth - much like the glass panes of a greenhouse.
If too much heat is trapped in the atmosphere, the theory is that it will cause the planet to overheat.
The report also studied ways of blocking sunlight, perhaps by creating high clouds of dust, or of absorbing carbon dioxide, such as by planting trees or causing more ocean plants to grow by sowing the seas with specific nutrients.
Some of the measures were found to be impractical. However, Thomas H. Lee, a Massachusetts Institute of Technology professor emeritus and chairman of the committee that produced the report, said the study will form a framework "for international negotiations concerning greenhouse warming."
But he cautioned: "There is no single silver bullet that can solve the problem."
The report said that although the United States is the world's largest producer of carbon dioxide and other greenhouse gases, the problem of global warming must be combated by all nations on the planet.
"The United States need to realize that although unilateral actions can contribute significantly to the reduction of greenhouse gases . . . national efforts alone would not be sufficient to eliminate the problem," the report said.
The principal gas being emitted into the atmosphere is carbon dioxide, a waste produced mainly by burning gasoline, oil, coal and other carbon-based fuels.
Some industrial gases, such as chlorofluorocarbons or CFCs, can also contribute to the global warming threat.