Potential Effects

The Panel on Climate Change reports a rise in average global temperature of one degree Fahrenheit during the past century-- about 20 times faster than the average rate of change. The accelerating warming has been occurring just as the models have predicted-- during the time when greenhouse gases in the atmosphere (about eighty percent CO₂) have increased rapidly, reports James Hansen. (Hileman 17) Moreover, emission of heat-trapping gases is forecasted to raise global temperature further by 1.8 to 6.3 degrees Fahrenheit, with a best estimate of 3.6 degrees, by the year 2100. This calculated temperature rise is only an average, however, it suggests that the polar regions would warm by two to three times the average, due to factors such as thin ozone and melting glaciers, while warming in the tropics would be limited to 50-75 percent of that average. (Mintzer 141) In fact, the Northern hemisphere has already set a new record at 2.26 degrees F above normal, with the tropical latitudes also reaching a new record 1.8 degrees Fahrenheit over normal.

Heat Wave

Summer heatwaves across the southern United States subjected Tampa, Florida to 12 days where nighttime temperatures failed to drop below 80 F, and Melbourne, Florida to 24 days of temperatures reaching 95 F or higher. Dallas experienced 29 consecutive days in which temperatures exceeded 100 F, claiming the lives of over 100 Texans. An unprecedented Fall heat wave from November to early December broke or tied more than 700 monthly temperature records from the East Coast to the Rocky Mountains. For the first time ever recorded, Glasgow, Montana had no days with subzero temperatures.

---taken from: Mohr, Noam, and Katherine Silverthorne. Flirting With Disaster: Global Warming and the Rising Costs of Extreme Weather. United States Public Interest Research Group Education Fund. 27 Oct. 1999. 6 Feb. 2000

Evidence pouring in from many different fields indicates a speedup in the rise of the Earth's surface temperature. Globally, eleven of the past sixteen years have in turn been the hottest of the century, according to a NASA report (Hileman 17). In 1989, researchers at Ohio State University reported the discovery of ice cores, taken from glaciers in Central Asia, which physically show striking temperature increase over the past 100 years (Newton 16). "When "proxy" records-- such as tree rings, pollen, sediments, and gases trapped in glaciers-- are used to estimate global temperatures in the distant past...1998 stands out as a record hot year for the millennium," says Michael E. Mann, professor of geosciences at the University of Massachusetts, Amherst (qtd. in Hileman 17). This figure is all the more remarkable because it was established at a time when two natural warming influences were neutralized: the solar energy cycle was at a low ebb and the warming effect of El Nino was offset by a turn to cooler than normal conditions in the tropical Pacific later in the year (David Schneider 13). In addition to these neutralized warming influences, the June 1991 eruption of Mount Pinatubo in the Philippines produced a sun-reflecting haze that actually cooled the earth for two years. This eruption blew megatons of volcanic ash and sulfuric acid into the stratosphere, emitting enough particles to reflect and thus reduce the amount of heat reaching the earth's surface (Begley 24). As a direct result of the planet's temperature rise, record heat waves and drought conditions have occurred all over the world. The Middle East has undergone its worst drought in 50 years. In Iran, the most extreme drought in decades has destroyed over a quarter of the country's wheat and rice crops. Places as diverse as Russia, Uganda, Spain, Vietnam, Kiribati, and China have also suffered severe drought conditions.