Last year was the hottest since the National Weather Service began keeping records in 1951. Scientists have observed that the timing of seasons has shifted in the Northern Hemisphere over the past 20 years or so, and an iceberg the size of Rhode Island recently broke off from Antarctica, apparently because that continent has gotten four Fahrenheit degrees warmer since 1940.

Is global warming sci-fi? Environmental extremism? An authoritative September 1995 report from the U.N. offered the first mainstream scientific consensus that human activity is at least partly responsible for global warming. This followed a March agreement by the environment ministers of 167 nations to establish limits on GREENHOUSE GASES that will take effect soon after the turn of the century. The recognition that humankind is harming the earth's atmosphere is a welcome, if overdue, acknowledgement. But will the avarice of big business, national pride, and the fear of economic consequences prevent the required worldwide follow-through on such a commitment?