Whither the U.S. Climate Program?

摘要

Approximately 50 years ago, the first contemporary stirring within the scientific community about climate change began when Roger Revelle and Hans Suess wrote that "human beings are now carrying out a large-scale geophysical experiment." Since that time, the scientific community has made remarkable progress in defining the effect that increased concentrations of greenhouse gases could have on the global climate and in estimating the nature and scale of the consequences. The political discussion about how to respond to this threat has been less successful. Although a small vocal group of scientists continues to raise important questions about whether the data and the theory validate the projected trend in the climate, these views have been more than counteracted by the overwhelming consensus of scientists that the case for the projected climate change is solid. The 2001 assessment by the Intergovernmental Panel on Climate Change of the World Meteorological Organization projects that by the year 2100, there will be a global temperature increase of 1.4 to 5.8 degrees centigrade, a global sea level rise of 9 to 88 centimeters, and a significant increase in the number of intense precipitation events. The wide range of these estimates reflects differences in assumptions about population projections, technological developments, and economic trends that are used in constructing the scenarios.