Global Warming

The phrase "global warming" is one that gets used repeatedly by a lot of people. It slips in and out of conversations, but it seems to be the kind of issue that people imagine will just go away on its own. As a result, the problems resulting from global warming are becoming alarmingly more grave.

Global warming is not a new issue. The beginning of the Industrial Revolution brought many new inventions to simplify and make our lives easier. Such inventions included cars, household appliances, and plants that burn solid waste, fossil fuels such as oil, natural gas, and coal (epa.gov). Before the Industrial Revolution, humans caused very few gases to be released into the atmosphere, but now scientists say, through the burning of fossil fuels, a large population growth, and deforestation, humans are affecting the mixture of gases in the atmosphere (World Book 8; 232). This mixture of gases in the atmosphere is causing the worldwide problem known as global warming.

The Earth has a natural "greenhouse effect" which is caused by energy from the sun controlling the Earth's weather and climate, and heating the Earth's surface. In response to the sun, the Earth radiates energy back into space (Curtis 159). Atmospheric greenhouse gases such as water vapor, carbon dioxide, and other gases trap the energy, leaving the Earth and retaining it as heat, much like the glass of a greenhouse. This is a natural and necessary effect. Without it, temperatures on Earth would be much lower than they are now and life as it is today would not be possible. Thus, with the greenhouse

effect, the Earth's average temperature is a more comfortable and life-supporting 60 degrees Fahrenheit (World Book 8; 232).

The problems that have arisen with the greenhouse effect have occurred due to the increase in atmospheric greenhouse gases. Data collected over the last one hundred years, shows that the average land surface temperature has risen between .8 and one degree Fahrenheit. Precipitation has increased around one percent over the globe and the sea level has risen approximately 6-8 inches, approximately 1-2 inches of the rise caused by melting mountain glaciers and another 1-4 inches has resulted from the expansion of the ocean water as a result of the warmer ocean temperatures (Curtis 159).

Scientists believe that the increase in greenhouse gas concentration, especially of carbon dioxide, is being caused by the combustion of fossil fuels and other human activities. Fossil fuels burned to run cars and trucks, heat homes and businesses, and power factories are responsible for about 98% of the total U.S. emission of carbon dioxide, 24% of the methane emissions and 18% of nitrous oxide emissions (World Book 8; 232). Also contributing a significant share of emissions is the increase in agriculture, deforestation, landfills, industrial production, and mining. Scientists say that in 1997, the United States was responsible for the emission of about one-fifth of the total global greenhouse gases. The total amount of future emissions depends on a range of factors, economic, and technological policies, and institutional developments, making it difficult to estimate future emissions. Still, scientists predict that by the year 2100, without emissions control policies, carbon dioxide concentrations will be 30-150% higher than they are today. Scientists also expect that the earth's average surface temperature could rise 1.6 - 6.3 degrees Fahrenheit by 2100. It is also expected