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Hi, class! Did you know that Earth Day was first celebrated on 22 April 1970? From that day, Earth Day is celebrated all over the world. Are you aware that I AM in DANGER? Think about all the small things you can and should do to save me!! But can you still remember why I am so important to human beings?

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Air PollutionAir Pollution

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Water PollutionWater Pollution

44

DeforestationDeforestation

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Endangered SpeciesEndangered Species

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OverpopulationOverpopulation

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Global WarmingGlobal Warming Global warming, a recent warming , a recent warming

of the Earth's lower atmosphere, is of the Earth's lower atmosphere, is believed to be the result of the believed to be the result of the

greenhouse effectgreenhouse effect due to due to increased concentrations of increased concentrations of

greenhouse gases in the in the atmosphere. atmosphere.

The The greenhouse effectgreenhouse effect is the rise in temperature is the rise in temperature

that the Earth experiences that the Earth experiences because certain gases in because certain gases in the atmosphere (water the atmosphere (water vapor, carbon dioxide, vapor, carbon dioxide,

nitrous oxide, and nitrous oxide, and methane, for example) methane, for example)

trap energy from the sun.trap energy from the sun.

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The hole in the Ozone LayerThe hole in the Ozone Layer

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Garbage