The global warming describes the increase in the average temperature of the earth's surface.

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A Global warming is the progressive gradual rise of the earth's surface temperature thought to be caused by the greenhouse effect and responsible for changes in global climate patterns. An increase in the near surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. See climate change, greenhouse effect, enhanced greenhouse effect, radiative forcing.

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Global warming is the warming of the earth"s atmosphere because of increases in the concentrations of one or more greenhouse gases primarily as a result of human activities. See greenhouse effect, greenhouse gases.