Stratosphere

The stratosphere is an atmospheric layer that is stratified in temperature, with warmer layers higher up and cooler layers farther down. This is in contrast to the troposphere near the surface, which is cooler higher up and warmer farther down. The stratosphere sits directly above the troposphere and directly below the mesosphere.

The stratosphere is layered in temperature because it is heated from above by absorption of ultraviolet radiation from a sun. Within this layer, temperature increases as altitude increases. This top is called the stratopause, above which temperature again decreases with height. The 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.