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The Greenhouse Effect and Global Warming Recently, global warming has moved to a serious scientific issue. Because sunlight is constantly falling on the earth, the law of physics say that the planet has to radiate the same amount of energy back into space. Infra ....

Middle of Essay
.... hotter than it has been in 100,000 years. From the beginning of the industrial revolution, concentrations of carbon dioxide have increased by 30%, concentrations of methane have doubled, and nitrous oxide has risen by 15%. The increases of these chemicals have enhanced the heat trapping capability of the atmosphere of the earth. Sulfate aerosols, cool the atmosphere because they reflect light back into space, but sulfates do not live long in the atmosphere. Scientists still do not know what exactly is heating up the earth. Some say the earth is going through a natural cycle because the earth has gone through cold periods as well as hot periods ....