Global warming caused by the greenhouse effect is one of "the most serious and intractable problems" the world faces, and it is unlikely that significant progress will be made fighting it in the near future, U.S. Environmental Protection Agency Administrator William K. Reilly said Tuesday.
In an unusually pessimistic address before the Los Angeles World Affairs Council, Reilly said that "under our most optimistic control scenario, we could reduce global warming in the year 2025 by only one-fourth" of the four- to eight-degree temperature increase expected to occur by then.
And even achieving that will require massive economic and industrial restructuring, he said. "The world, I am afraid, is not yet ready for this," Reilly added.
Reilly said developing countries must play a central role in solving the problem because they are "potentially large contributors." But, he said, it will be "a great test of international diplomacy to involve the developing world" in efforts to control global warming.
The greenhouse effect refers to an accumulation in the atmosphere of carbon dioxide and certain other gases, such as the chlorofluorocarbons used in refrigerators and air conditioners. These gases allow sunlight to pass through them and strike the Earth's surface, but absorb heat radiated by the Earth and prevent it from escaping into space--much as the glass panes of a greenhouse trap the sun's warmth inside.
Carbon dioxide produced by the combustion of fossil fuels is the chief contributor to the greenhouse effect. In the century since the Industrial Age began, the amount of carbon dioxide in the atmosphere has increased by 25% and researchers predict that the concentration will double by the middle of the next century.
Two months ago, the EPA published a new study that said the Earth could warm an average of four to six degrees Fahrenheit by the year 2050 if rapid global economic development occurs without any serious attempt to limit emissions of greenhouse gases. The average temperature could rise 8 to 12 degrees by the year 2100 under that same scenario.
Researchers say such warming will have a huge impact on the world's climate. Prime agricultural areas would move northward from the United States into Canada and, across the Atlantic, from Western Europe into the Soviet Union. Midwestern states would experience droughts regularly and heat waves worse than those of last summer.
Polar ice caps would melt, raising ocean levels that would inundate shorelines throughout the world and destroy many island nations.
Using the same computer models with which they projected temperature increases, EPA researchers recently calculated the potential effect of controlling emissions of greenhouse gases.
Even under the most optimistic scenario, Reilly said, global warming would be reduced by only 25% by the year 2025 and the rate of climatic change reduced by only 60% during the next century.
But with that scenario, Reilly said, "We didn't dismiss options because of cost, or because of obvious political limitations. We simply asked, 'What's . . . possible?' "
Political leaders, he continued, have to ask "What's reasonable? What's politically plausible? What's a realistic time frame for action?" Such questions, he said, "starkly illustrate the unreality of optimistic scenarios."
Reilly said the most effective forms of intervention include massive reforestation, raising the cost of coal compared to less-polluting energy sources such as natural gas and relying more on solar and nuclear power.
"Any serious attempt to implement even a few of these proposals would generate great political controversy within the United States and elsewhere," Reilly said. In particular, he said, developing countries may resist the changes, believing that such changes would hinder their attempts to achieve a life style comparable to that of the United States.
Involving developing countries is crucial because the industrialized world now contributes 40% of the emissions of greenhouse gases and the percentage is declining.
The United States is trying to get developing countries "to reflect on the science involved" in greenhouse warming and other global problems, Reilly said. "If their scientists are involved," he explained, "maybe they will reach the same conclusions we have."