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Greenhouse gases and warming
Carbon dioxide and methane are greenhouse gases. Earth loses energy to space as infrared radiation. Greenhouse gases absorb and re-emit some of this radiation, reducing the rate at which energy escapes. Increasing their concentrations strengthens this effect and contributes to a rise in global mean temperature. Global warming refers to this long-term rise; it does not mean every location gets warmer every day. Weather still varies from place to place and from day to day.
