Global Warming In recent years, the term global warming has been associated with such phrases as “impending environmental disaster”, the “greenhouse effect” and “the most serious environmental threat of the 21st century” (Newton xi; Newton 87). Global warming is defined as an increase in the average temperature on Earth. The increase was first detected in the 1980’s. The cause of global warming is believed to be the greenhouse effect. This is the process of trapping heat with the Earth’s atmosphere due to the presence of large amounts of carbon dioxide, chlorofluorocarbons, methane and nitrogen oxides (“Globa