Stratosphere Stratosphere The stratosphere () is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. The stratosphere is stratified in temperature, with warmer layers higher and cooler layers closer to the Earth; this increase of temperature with altitude is a result of the absorption of the Sun's ultraviolet radiation by the ozone layer. This is in contrast to the troposphere, near the Earth's surface, where temperature decreases with altitude. The border between the troposphere and stratosphere, the tropopause, marks where this temperature inversion begins. Near the equator, the stratosphere starts at as high as ,
UV filter nm), UVB (290-320 nm) and UVC (200-280 nm ). Ultraviolet absorbing compounds are the active ingredients of sunscreen products and other personal care products (e.g. lipsticks, shampoos, hair sprays, body washes, toilet soaps, and insect repellents). Chemical filters are generally used in combination in order to get sufficient protection against UV. They protect humans from the serious effects of UV radiation by absorbing, reflecting or scattering it. The reflection and scattering effecst are done by physical UV filters which are inorganic UV filters such as titaniumdioxide (TiO) and zinc oxide (ZnO). Absorption is accomplished by organic UV filters which are