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Welfare Effects - Greenhouse Effect
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The earth's climate is fueled by the sun. Most of the sun's energy, called solar radiation, is absorbed by the earth, but some is reflected back into space. Clouds and a natural layer of atmospheric gases absorb a portion of earth's heat and prevent it from escaping into space. This keeps our planet warm enough for life and is known as the natural "greenhouse effect". Without the natural greenhouse effect, the earth's average temperature would be much colder, and the planet would be uninhabitable. Scientific evidence shows that the greenhouse effect is being increased by the release of certain gases into the atmosphere that cause the earth's temperature to rise. This is called "global warming." Carbon dioxide, methane, particulate matter (especially black carbon or soot), nitrous oxide, fluorinated compounds, and ozone are some of the compounds contributing to global warming. Carbon dioxide accounts for about 81 percent of greenhouse gases released in the United States. Carbon dioxide emissions are largely due to the combustion of fossil fuels in electric power generation, motor vehicles, and industries. Methane emissions, which result from agricultural activities, landfills, and other sources, are the next largest contributors to greenhouse gas emissions in the United States and worldwide.
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Continued emissions of greenhouse gases could cause a 2.5° to 10° Fahrenheit rise in temperature by the year 2100. This could lead to more extreme weather events such as droughts and floods, threaten coastal resources and wetlands by raising the sea level, and increase the risk of certain diseases by producing new breeding sites for pests and pathogens. Agricultural regions and woodlands are also susceptible to changes in climate that could result in increased insect populations and plant disease. This degradation of natural ecosystems could lead to reduced biological diversity.
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