Stratosphere and Stratopause

Having discussed the troposphere and its upper boundary, the tropopause, we’ll now look at the next layer in the atmosphere called the stratosphere. The stratosphere extends from the tropopause up to about 50 kilometres above the Earth’s surface.

The temperature structure of the stratosphere is dominated by the presence of ozone. Ozone is formed when solar radiation splits oxygen into its two individual atoms. These free atoms combine to form the gas called ozone. This process releases energy into the surrounding air and therefore heats up the part of the atmosphere.

Concentrations of ozone are at a maximum at around 20 to 25 kilometres above the Earth’s surface. Due to latitude effects and the depletion of ozone during the polar winter, the temperature through this part of the stratosphere can vary from minus 30 to plus 20 degrees Celsius annually.

If you are carrying out a stratospheric flight, you would are not likely to encounter any weather phenomena like clouds. That is because there is no humidity or water vapour in the stratosphere. The clouds found in stratosphere are Nacreous and Mother of Pearls clouds, which are formed without water vapour content.

The height where the temperature stops rising further marks the upper boundary of the stratosphere. This boundary is called the Stratopause.