Should the U.S. sign the Kyoto Protocol? It was supposed to commit nations to solving global warming. But opponents question whether the treaty would even help. (opinion).

YES Global warming could profoundly affect human health and livelihoods as well as natural ecosystems around the globe. The good news is that we know how to start solving the problem now.

Global warming is caused by the buildup of carbon dioxide and other so-called greenhouse gases in the atmosphere due to the burning of fossil fuels, such as coal and oil. Scientists predicted this effect more than 100 years ago, and extensive research by experts all over the world confirms it.

Officials recently pronounced 2001 the second-hottest year on record. Unless the pollution that casues global warming is reduced, temperatures in the U.S. could rise an average of 5 to 10 degrees Fahrenheit within the next 100 years.

That could have a dramatic impact on the planet: rising seas and coastal flooding; melting glaciers; hotter heat waves; more weather extremes, meaning bigger storms and more droughts; and more wild species pushed to extinction.

In 1997, the U.S. and 170 other countries backed a treaty called the Kyoto Protocol--named for the Japanese city where it was written--requiring industrial countries to reduce their pollution. Poorer countries would work with richer ones to develop solutions too, but would not yet have to cut emissions. The U.S. Senate never ratified the Kyoto agreement. Then last year, President Bush withdrew support, saying it would be bad for the economy.

This is a mistake. The U.S. should sign the Kyoto Protocol, because solving global warming means cleaning up all kinds of pollution and saving energy, which always makes good sense.

Possible solutions include more fuel-efficient cars and pollution-free energy technologies like wind, solar, and fuel cells that would improve our living standard without trashing the environment. This would be good for business since America leads the world in many of these technologies.

Hopefully, the U.S. will rethink the Kyoto Protocol, and rejoin the world effort to solve global warming. In the meantime, Congress is considering bills to improve fuel efficiency and clean up power plants--steps that will start us in the right direction.

--DAVID HAWKINS Natural Resources Defense Council 

NO The United States is right to reject the 1997 Kyoto Protocol, because the treaty would be too expensive to implement and there is not enough proof that it would solve global warming, or that global warming is even a problem that needs solving.

First of all, there's simply no evidence yet that mankind has anything to do with the modest amount of global warming we've experienced so far. As the most recent report of the UN's International Panel on Climate Change points out, there is no "compelling evidence of a clear cause-and-effect link" between industrial pollution and the detectable warming of the Earth's climate. The report goes on to speculate about whether it might be possible to make that connection in the future, and concludes that no one knows for sure. The assertion that we already know that industrial emissions are behind global warming is simply dead wrong.

Reducing the amount of greenhouse gases we put into the atmosphere by the amount stipulated in the Kyoto Protocol would cost more than 4 percent of the entire American economy each year, according to the federal Energy Information Administration. That's about the size of the current defense budget--and is a sum larger than the cost of all our current environmental regulations combined.

Besides, even if global warming is as bad as some environmentalists think, the Kyoto Protocol would not produce the desired effect. Computer simulations show it would only reduce global temperatures by a tiny fraction of 1 degree Fahrenheit by 2050. This is not enough to justify the enormous cost.

The only way to reduce our use of coal, oil, and gas is to increase the price of those fuels. But higher energy costs would harm the poor more than anyone else. In Third World countries, higher energy costs would only prevent industry from growing and keep people in poverty. This is the real price of supporting the Kyoto Protocol, and it is too high.

--JERRY TAYLOR Director Natural Resource Studies, The Cato Institute