Warming up, indubitably
Much has changed in the six years since the United Nations' climate change panel last reported on the "different planet" humans are creating through greenhouse gases. The evidence that carbon dioxide emissions from fossil fuel combustion are heating the Earth is stronger than ever. The new panel's confirmation that ocean warming is magnifying the strength of Atlantic hurricanes will raise the stakes of climate change in much of the Western Hemisphere. But what has not changed is the unwillingness of the United States, the single largest source of greenhouse gas emissions, to take the lead in reducing them.
It is progress of a sort that President Bush has stopped denying the science of climate change and even mentioned it in a State of the Union address, as he did last month. But he continues to balk at limits on carbon emissions, whether through a tax on them or through a cap-and-trade system, the approach that has worked so well in reducing the pollutants that cause acid rain. He is maintaining his opposition to carbon limits even after 10 of the nation's leading corporations, including
If anything, the UN report released Friday understates the effects that carbon emissions will have. Because of the report's lengthy review process by both scientists and representatives of 113 governments, the most recent evidence of ice melting in Greenland and elsewhere could not be fully included in the final document. Nor could the report include the latest evidence that melting permafrost in Siberia and elsewhere is causing the release of large amounts of methane, a far more damaging greenhouse gas than carbon dioxide.
Despite those omissions, the report projects increases in temperatures and sea levels that will lead to devastating floods, hurricanes, and droughts. "It's later than we think," said Susan Solomon, co chairman of the Intergovernmental Panel on Climate Change. The scientists who wrote the report emphasize that global warming cannot be stopped, only slowed. But doing so will reduce the cost of adapting to it, they argue, and limit its impact in lives lost and habitats destroyed.
The US government has had plenty of warning that emissions from its cars, factories, and power plants would have a greenhouse effect. "This generation has altered the composition of the atmosphere on a global scale through . . . a steady increase in carbon dioxide from the burning of fossil fuels," a president once told Congress. That was Lyndon B. Johnson in February of 1965. Forty-two years later, Congress must overcome the current president's intransigence and make the United States a leader in creating an agreement on carbon limits that will enlist both the industrial and the developing worlds.
