We’ve all heard the term global warming, but what does it mean? Is it serious? Global warming refers to the average increase in temperature of the planet. The Earth’s temperature has increased by about 1°F over the past 100 years. The greenhouse effect makes the earth warmer by trapping energy in the atmosphere. Changes in temperature have a direct impact on the Earth’s climate. Although scientists are unsure exactly of the climate changes that will take place due to global warming, some project changes in annual rainfall and rising sea levels. These changes have a direct effect on plants, wildlife, and humans. Which environmental changes do some scientists predict will take place due to global warming? A. less fish and plant life B. changes to annual rainfall and rising sea levels C. hotter weather in some areas and cooler weather in others D. none of the above