Stratosphere around at midlatitudes, and at about at the poles. Temperatures range from an average of near the tropopause to an average of near the mesosphere. Stratospheric temperatures also vary within the stratosphere as the seasons change, reaching particularly low temperatures in the polar night (winter). Winds in the stratosphere can far exceed those in the troposphere, reaching near in the Southern polar vortex. The mechanism describing the formation of the ozone layer was described by British mathematician Sydney Chapman in 1930. Molecular oxygen absorbs high energy sunlight in the UV-C region, at wavelengths shorter than about 240 nm. Radicals produced
UV coating UV coating A UV coating is a surface treatment which either is cured by ultraviolet radiation, or which protects the underlying material from such radiation's harmful effects. Ultraviolet cured coatings can be applied over ink printed on paper and dried by exposure to UV radiation. UV coatings can be formulated up to 100% solids so that they have no volatile component that contributes to pollution. This high solids level also allows for the coating to be applied in very thin films. UV coatings can be formulated to a wide variety of gloss ranges. UV coating can be applied via most