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How does the Sun warm Earth through thermal radiation?

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heating In a thermoelectric generating system a heat source—usually fueled by coal, oil, or gas—is used within a boiler to convert water to high-pressure steam. The steam expands and turns the blades of a turbine, which turns the armature of a generator, producing electric power. A condenser converts any remaining steam to water, and a pump returns the water to the boiler.

The Sun warms Earth through the process of thermal radiation, which involves the transfer of energy in the form of electromagnetic radiation. Unlike other heat transfer methods, thermal radiation does not require an intervening medium to travel through space, allowing solar energy to reach Earth at the speed of light.1

This energy, often referred to as "shortwave" radiation, consists of wavelengths ranging from ultraviolet to infrared. Upon reaching Earth, a portion of this radiation is reflected back into space by clouds, the atmosphere, and the surface, while the remainder is absorbed by the planet. This absorption process is the primary mechanism by which the Sun heats Earth’s surface.1234

Once absorbed, this energy is systematically returned to space as "longwave" infrared radiation. The atmosphere plays a critical role in this cycle by trapping some of this outgoing heat—a process known as the greenhouse effect—which maintains the planet's surface temperature at a level capable of supporting life.32