A crop-searing drought grips the Midwest and Southeast. In the Rocky Mountains, extraordinary "superfires" rip through thousands of acres of high-elevation pine. The Mississippi River runs so low that barge traffic must be slowed, at times suspended. Across the country, roads buckle under the heat. The year is 1988, and for the first time, a majority of Americans are waking up to a disconcerting phenomenon known as the greenhouse effect.