Leading U.S. climate scientists are worried that the American public and political parties appear to be apathetic about the threat of global warming. The experts argue that action to counter it should be taken now, even though science has not answered many questions about global warming.
Researchers who gathered in Washington Tuesday for a meeting on climate change warned that despite the imperfect state of knowledge, enough is known about global warming to cause grave worry and incite action. They point out that melting polar ice caps are causing sea levels to rise, spring is appearing a little earlier than in the past, and plant and animal distribution is shifting northward.
University of Washington scientist David Battisti says current trends in emissions from fossil fuels like gasoline and coal indicate that carbon dioxide levels in the atmosphere will triple in the next 150 years, thickening the gas blanket around Earth that traps heat like a greenhouse.
"It's going to be a very different world and it's going to be a much warmer world, and there are reasons to believe that the projections with the models we have now are actually underestimating those changes," he said.
An international scientific consensus has been forged under United Nations auspices that average global temperatures have risen between half and one degree Celsius in recent decades. The UN Intergovernmental Panel on Climate Change predicts they will continue to increase by one-and-a-half to nearly six degrees by the end of this century.
The 1997 Kyoto Protocol commits more than 120 signing nations to reducing emissions of the so-called greenhouse gases, but President Bush withdrew the United States from the agreement soon after taking office in 2001. Advisors to the president, like Conrad Lautenbacher of the US Oceans and Atmospheric Agency (NOAA), express doubts about the accuracy of the scientific predictions.
"Nobody is arguing in this country that we don't need to stabilize greenhouse gases. I think the argument is, how fast do you do it and what means do you use to accomplish that end? You have to know quite a bit about what's going on in the science side before you can make an intelligent choice as to what to do on the policy side, because many of these choices involve billions and trillions of dollars of economic dislocation and social dislocation," he said.
But the climate experts meeting in Washington argue that global warming has advanced to the point where corrective steps enacted now would take many decades or longer to begin reversing its impact. David Battisti says cutting emissions by 95 percent will still allow a doubling or tripling of carbon dioxide levels by the next century, but would prevent them from rising even more.
Harvard University scientist Daniel Schrag says doing something now is like taking out an insurance policy against a catastrophe. He does not believe the Bush administration will act, but notes that this is a presidential election year in the United States.
"I don't think that we should expect to convince this administration in the next few months to change its position. My suspicion is that there is a possibility if there is a change in government," he said.
Princeton University environmental scientist Michael Oppenheimer says both major U.S. political parties have acted badly on global warming, but expresses hope that legislation by state governments will eventually incite nationwide measures.
"I don't think you need to take too bleak a view. Things are happening. The history of U.S. clean air law is that action started at the state level and percolated up to the federal level when companies came in and demanded uniformity," he said.
Mr. Oppenheimer points to proposed regulations in the largest U.S. state, California, that would cut automobile emissions by 30 percent and raise prices several hundred dollars for cars that consume the most fuel. He says other states are also beginning to implement stricter emissions standards.