THE EARTH ATMOSPHERE
The Troposphere is where all weather takes place; it is the region of rising and falling packets of air. the air pressure at the top of the troposphere is only 10% of that at seal
in the upper stratosphere has a high concentration of ozone, a particularly reactive form of oxygen. This layer is primarily responsible for absorbing the ultraviolet radiation from the Sun. The formation of this layer is a delicate matter, since only when oxygen is produced in the atmosphere can an ozone layer form and prevent an intense flux of ultraviolet radiation from reaching the surface, where it is quite hazardous to the evolution of life.