Global warming is caused by greenhouse effect. Greenhouse effect will occur correctly if the quantity of the greenhouse gases are not over. Greenhouse gases are gases in atmosphere that absorb and emit radiation within the thermal infrared range. Greenhouse gases contain Carbon Dioxide(CO2), Water Vapor, Methane, CFC, Nitrous Oxide, Ozone. Because of human's bad habit, the quantity of greenhouse gases increase extremely. It makes greenhouse gases reflect too much radiation into the earth. So, it will trap too much radiation inside the earth and make the earth become hot.
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