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Skin Temperature (of An Atmosphere)
The skin temperature of an atmosphere is the temperature of a hypothetical thin layer high in the atmosphere that is transparent to incident Sunlight, solar radiation and partially absorbing of Infrared, infrared radiation from the planet. It provides an approximation for the temperature of the tropopause on terrestrial planets with greenhouse gases present in their atmospheres. The skin temperature of an atmosphere should not be confused with the ''surface skin temperature'', which is more readily measured by satellites, and depends on the thermal emission at the surface of a planet. __TOC__ Background The concept of a skin temperature builds on a radiative-transfer model of an atmosphere, in which the atmosphere of a planet is divided into an arbitrary number of layers. Each layer is Transparency and translucency, transparent to the visible radiation from the Sun but acts as a Black body, blackbody in the infrared, fully absorbing and fully re-emitting infrared radiation origi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atmosphere
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere is the outer region of a star, which includes the layers above the opaque photosphere; stars of low temperature might have outer atmospheres containing compound molecules. The atmosphere of Earth is composed of nitrogen (78%), oxygen (21%), argon (0.9%), carbon dioxide (0.04%) and trace gases. Most organisms use oxygen for respiration; lightning and bacteria perform nitrogen fixation which produces ammonia that is used to make nucleotides and amino acids; plants, algae, and cyanobacteria use carbon dioxide for photosynthesis. The layered composition of the atmosphere minimises the harmful effects of sunlight, ultraviolet radiation, solar wind, and cosmic rays and thus protects the organisms from genetic damage. The curr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
