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Global Warming |
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Water vapour, carbon dioxide and methane form a natural blanket of air around the Earth. However, the burning of fossil fuels and deforestation has led to a massive increase in the amount of carbon-dioxide released into the atmosphere.We are also releasing larger quantities of other greenhouse gases, such as methane, CFCs and nitrous oxide. |
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The surface of the earth is heated by the sun. As it warms up, it reflects heat back into the atmosphere. |
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As a result of the greenhouse effect, the Earth is kept warm enough to make life possible. But some scientists say that increased emissions of greenhouse gases are disturbing the balance of this complex system, causing global warming. In the last 100 years, the average global temperature has increased by about 0.4 to 0.8 degree celsius. |
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About 70% of the sun's energy is radiated back into the space. But some of the infrared radiation is trapped by greenhouse gases, which warm the atmosphere, and reflect heat back down to Earth. |
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