Diffuse radiation
The electromagnetic radiation emitted by a radiation source is reflected , absorbed / re-emitted, scattered , diffracted or refracted when it hits an obstacle during its propagation . The result of the radiation, which is generally unevenly changed in the direction of propagation , radiation intensity , wavelength and / or frequency , is referred to as diffuse radiation or diffuse radiation or scattered radiation . Direct radiation is to be distinguished from this .
In the special case of the earth radiation budget, this is called diffuse sunlight or diffuse radiation , so that part of the earth's surface incoming solar radiation that the Earth's atmosphere interacted. The short-wave diffuse radiation occurs mainly during the day in combination with direct solar radiation, at night there is a significantly weaker sky radiation from the light of stars , polar lights and scattered light sources on the earth's surface. The direct and diffuse short-wave solar radiation together represent the global radiation . In addition, there is the permanent, long-wave atmospheric counter-radiation of the most important greenhouse gases , which is sometimes also referred to as long-wave sky radiation .
The visible spectrum of short-wave diffuse radiation is light from the sky .
The diffuse and direct sky radiation can be measured with an actinometer .
Individual evidence
- ↑ a b sky radiation. In: Spectrum Lexicon of Physics. Retrieved April 17, 2020 .
- ^ Rüdiger Glaser, Christiane Hauter, Dominik Faust, Rainer Glawion, Helmut Saurer, Achim Schulte, Dirk Sudhaus: Physical geography . Springer, 2016, ISBN 978-3-662-50461-1 , pp. 78-79 .
- ↑ sky radiation. In: Spectrum Lexicon of Geography. Retrieved April 17, 2020 .