At sea level, the air pressure is about 14.7 pounds per square inch. In the thermosphere, temperature increases with altitude. The thermosphere includes the exosphere and part of the ionosphere. The ions are created when sunlight hits atoms and tears off some electrons.
Auroras occur in the ionosphere.
The mesosphere is characterized by temperatures that quickly decrease as height increases. The stratosphere is characterized by a slight temperature increase with altitude and the absence of clouds. The earth's ozone layer is located in the stratosphere. The tropopause is characterized by little or no change in temperature altitude increases. The weather and clouds occur in the troposphere.