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 ,
Atmosphere of Uranus spots and noticeable seasonal changes. (see below) The stratosphere is the middle layer of the Uranian atmosphere, in which temperature generally increases with altitude from 53 K in the tropopause to between 800 and 850 K at the base thermosphere. The heating of the stratosphere is caused by the downward heat conduction from the hot thermosphere as well as by absorption of solar UV and IR radiation by methane and the complex hydrocarbons formed as a result of methane photolysis. The methane enters the stratosphere through the cold tropopause, where its mixing ratio relative to molecular hydrogen is about 3,