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The English version of our glossary is currently under construction and will be regularly updated.

Thermal infrared radiation

Thermal radiation emitted by land surfaces or objects in the longwave infrared range.

Radiation emitted by the Earth’s surface, the atmosphere and clouds in the longwave infrared range. Also known as “terrestrial” or “longwave” radiation, it should not be confused with near-infrared radiation, which is part of the solar spectrum. Generally speaking, infrared radiation has a characteristic range of wavelengths that are longer than those of the colour red in the visible range. Due to the temperature difference between the sun and the Earth / atmospheric system, the spectrum of thermal infrared radiation can be clearly distinguished from shortwave or solar radiation.