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Global warming is the long-term rise in the average temperature of the Earth's climate system. It is a major aspect of climate change, and has been demonstrated by direct temperature measurements and by measurements of various effects of the warming.
Global warming is a gradual rise in the average temperature of the Earth's climate system. This increase in temperature is largely caused by the increased emissions of carbon dioxide and other greenhouse gases. These gases are trapping more heat and energy in the atmosphere, leading to a gradual rise in global temperatures. Human activities, such as burning coal and other fuels, are the primary source of these emissions. As a result, climate change is leading to more extreme weather, sea level rise, and species loss.