The Greenhouse Effect is a natural process by which certain gases in the atmosphere trap infrared radiation (heat) that would otherwise escape the planet, keeping the Earth about 60˚F warmer than it would otherwise be (i.e. really cold!).  All scientific evidence suggests that human activities (fossil fuel burning, deforestation, etc) have added large amounts of those "greenhouse gases" to the atmosphere, increasing the amount of heat trapped, and thus warming the planet by a small but measurable amount, and are responsible for at least some of the current issues relating to climate change.



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