insolation

radiant energy

Also known as: incoming solar radiation, shortwave radiation

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July 17, 2026

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Insolation refers to the amount of solar radiation received by a surface. This radiant energy originates from nuclear fusion within the Sun and is transferred into space. A portion of this energy reaches Earth, with a 1-square-meter area perpendicular to the Sun's rays at the top of the atmosphere receiving approximately 1,365 watts of solar power.12

While about 31 percent of this incoming solar energy is reflected back into space, the remainder powers atmospheric and oceanic movements, and sustains most life on Earth. The intensity of insolation is influenced by factors such as latitude, the time of year, and the time of day, as these affect the solar elevation angle and the length of daylight.2

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atmosphere
Radiation
…traditionally divided into two types: insolation from the Sun and emittance from the surface and the atmosphere. Insolation is frequently referred to as shortwave radiation; it falls primarily within the ultraviolet and visible portions of the electromagnetic spectrum and consists predominantly of wavelengths of 0.39 to 0.76 micrometres (0.00002 to…
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…traditionally divided into two types: insolation from the Sun and emittance from the surface and the atmosphere. Insolation is frequently referred to as shortwave radiation; it falls primarily within the ultraviolet and visible portions of the electromagnetic spectrum and consists predominantly of wavelengths of 0.39 to 0.76 micrometres (0.00002 to…
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Milutin Milankovitch
Milankovitch cycles
…amount of solar radiation (insolation) that strikes Earth’s surface at different latitudes in different seasons. Because they operate on different timescales, the parameters affect climate by interacting in a manner that sometimes increases and sometimes decreases the insolation at a particular location.
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…amount of solar radiation (insolation) that strikes Earth’s surface at different latitudes in different seasons. Because they operate on different timescales, the parameters affect climate by interacting in a manner that sometimes increases and sometimes decreases the insolation at a particular location.
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