The stratosphere is the second major layer of air in the atmosphere. It resides between 10 and 50 km above the planet's surface. The air temperature in the stratosphere remains constant up to an altitude of 25 km. It then increases gradually to 200-220 degrees Kelvin at the lower boundary of the stratopause, which is marked by a decrease in temperature. Air temperatures increase with altitude in the stratosphere, which has a stabilizing effect on atmospheric conditions.
Ozone plays the major role in regulating temperature.
Temperatures increase as the ozone concentration increases. Solar energy is converted to kinetic energy when ozone molecules absorb ultraviolet radiation in heating the stratosphere. The mesosphere extends from approximately 50 km to 80 km. It is characterized by decreasing temperatures, which register at about 190-180 K and at an altitude of 80 km. Because there are decreased concentrations of ozone and water vapor, the temperature is lower than in the troposphere or stratosphere.