Transcript Document
The Greenhouse Effect What are greenhouse gases? Energy from the sun heats the earth’s surface; in turn, the earth radiates energy back into space. Atmospheric GHG trap some of the outgoing energy, retaining heat somewhat like the glass panels of a greenhouse. Without this natural greenhouse effect, temperatures would be much lower than they are now, and life would not be possible. With greenhouse gases, the temperature of the earth is warm for life. Naturally occurring GHG that are affected by human activities - - - Carbon dioxide (CO2)is released by combustion of fossil fuels (oil, natural gas and coal), and wood decomposition of organic matter *deforestation - - Methane (CH4) is emitted during the production and transport of coal, natural gas and oil. by the decomposition of organic wastes in solid waste landfills Naturally occurring GHG that are affected by human activities - - Nitrous oxide (N2O) is emitted during agricultural and industrial activities combustion of solid waste and fossil fuels Ozone (O3) is destroyed by CFCs (chlorofluorocarbons) Ozone layer in the upper atmosphere helps blocking out the harmful rays that cause skin cancer. Human-induced GHG that are not naturally occurring - Hydrofluorocarbons (HFCs) are generated in a variety of industrial processes - Perfluorocarbons (PFCs) are generated in a variety of industrial processes Human-induced GHG that are not naturally occurring - Sulfur hexafluoride (SF6) are generated in a variety of industrial processes Chlorofluorocarbons (CFCs) is released from air conditioners Refrigerators Aerosols Chlorine is the main compound which reduces the ozone layer in the upper atmosphere