The greenhouse effect involves the absorption and emission of infrared radiation by various gases in the Earth's atmosphere, commonly known as greenhouse gases. Here's a simplified breakdown of the process:
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Solar Radiation: The sun emits energy primarily in the form of visible light and some infrared radiation. This energy reaches the Earth, where a portion is absorbed by the surface, warming the planet.
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Emitted Infrared Radiation: As the Earth’s surface absorbs this solar energy, it warms up and then emits energy back into the atmosphere in the form of infrared radiation (longwave radiation).
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Absorption by Greenhouse Gases: Certain gases in the atmosphere, such as carbon dioxide (CO2), methane (CH4), water vapor (H2O), and others, absorb this emitted infrared radiation. These gases have molecular structures that allow them to vibrate and rotate when they encounter infrared wavelengths, effectively trapping some of that energy.
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Re-emission: After absorbing infrared radiation, greenhouse gases eventually re-radiate the energy in all directions, including back toward the Earth’s surface. This process contributes to warming the lower atmosphere and the Earth’s surface, enhancing the greenhouse effect.
In summary, the greenhouse effect involves the admission of far infrared radiation emitted from the Earth, which is then absorbed by greenhouse gases, contributing to planet-wide warming.