Global Warming

Scientists used the phrase "global warming" to describe the atypical increase in the Earth's surface temperature since the beginning of the 20th century. They increasingly prefer the use of the phrase "climate change," however, to describe the complex changes the Earth's climate is undergoing, according to the National Academies. 

Human Activities

Concern about global warming and climate change grew out of the evidence that human activities contribute to the release of greenhouse gases that can cause not only changes in temperature, but wind patterns, rainfall and snowfall. People are altering the composition of the atmosphere with emissions from transportation, agriculture, manufacturing and many other activities. 

Greenhouse Effect

The greenhouse effect is a vital natural process that prevents all of the sun's heat from simply reflecting back out into space. Clouds and greenhouse gases such as carbon dioxide naturally trap a portion of the sun's heat. Without greenhouse gases, the planet would be 60 degrees colder and life could not exist in these conditions. (See References 1, page 2) Humans produce greenhouse gases, such as carbon dioxide, nitrous oxide and methane, by burning fossil fuels to power homes and factories, generating waste and cutting down trees. Since 1750, the concentration of carbon dioxide in the atmosphere has increased over 36 percent, methane has increased over 148 percent and nitrous oxide has increased over 18 percent. 

Warming Rate

Since the early 20th century, the global temperature has warmed at a rate of about 1.3 degrees F. Scientists from the Intergovernmental Panel on Climate Change conclude that most of the warming since the 1950s has occurred because of human activities that increase greenhouse gas emissions. If we continue to produce greenhouse gases at even the current rate, by 2100 the average global temperature will likely increase 3 to 7 degrees F. 

United States Role

The United States is one of the largest contributors of global warming pollution, despite a recession-related drop in U.S. carbon dioxide emissions in 2009. Carbon dioxide in Earth's atmosphere increased in 2009, and projections are for continued increases in global CO2 emissions. 

Significance

The increasing temperature of the planet due to global warming will produce heat waves, declining air quality and illnesses carried by insects that proliferate in warmer temperatures. Effects on wildlife habitats and migratory patterns may cause some species extinctions if they are unable to adapt. A warming climate may cause common occurrences of floods and droughts, rising sea levels and violent storms. 

Solution

Reducing the pollution created by power plants and automobiles will help put a stop to global warming. Drive a well-maintained fuel-efficient vehicle; carpool, if possible. Conserve energy in your home by purchasing energy-efficient appliances and lighting, and weatherizing your home. Choosing renewable energy sources that use solar energy and wind to generate power can help combat global warming.