Greenhouse Gases: Too Much of a Good Thing
Human activity increases the amount of greenhouse gases in the atmosphere—mainly carbon dioxide from the burning of fossil fuels (coal, oil, and natural gas). The extra greenhouse gas may be trapping too much heat, abnormally raising Earth’s temperatures.
Although Earth’s average temperature fluctuates naturally, the current rapid rise in temperatures—global warming—is potentially harmful to life on Earth. The summer of 2003 was the hottest since 1500 and was responsible for 11,000 deaths in France alone. The National Science Foundation predicts that at the current rate of production of greenhouse gases, killer heat waves will be longer and more frequent.