Stratosphere the stratosphere temperatures increase with altitude "(see temperature inversion)"; the top of the stratosphere has a temperature of about 270 K (−3°C or 26.6°F). This vertical stratification, with warmer layers above and cooler layers below, makes the stratosphere dynamically stable: there is no regular convection and associated turbulence in this part of the atmosphere. However, exceptionally energetic convection processes, such as volcanic eruption columns and overshooting tops in severe supercell thunderstorms, may carry convection into the stratosphere on a very local and temporary basis. Overall the attenuation of solar UV at wavelengths that damage DNA by the ozone layer allows
Optical radiation Optical radiation Optical radiation is part of the electromagnetic spectrum. It is subdivided into ultraviolet radiation (UV), the spectrum of light visible for man (VIS) and infrared radiation (IR). It ranges between wavelengths of 100 nm to 1 mm. Electromagnetic waves in this range obey the laws of optics--they can be focused and refracted with lenses, for example. Optical radiation may be produced by artificial sources, such as UV lights, common lightbulbs, and radiant heaters, but the primary source of exposure for most people is the sun. This exposure can result in negative health effects. All wavelengths across this range