Epa 608 Qwik Study Guide March 2018

Ozone in the stratosphere above the Earth consists of molecules containing 3 oxygen atoms (O3).

The oxygen we breathe contains two atoms in each molecule.

The ozone layer consists of ozone in the stratosphere at an altitude of between 7 and 28 miles above the Earth.

The ozone layer, which is formed by ultraviolet (UV) light from the sun acting on oxygen molecules, absorbs and scatters UV light from the sun, thus preventing harmful amounts of UV light from reaching the Earth. For this reason the ozone layer is often referred to as the ozone shield.

Ozone in the lower atmosphere where we breathe it is caused by UV radiation from the sun acting on smog and air pollutants especially on hot summer days.

Ozone in the lower atmosphere where we breathe it is caused by UV radiation from the sun acting on smog and air pollutants especially on hot summer days.

Ozone at ground level is a harmful pollutant; in the stratosphere, it is a protective shield.

Ozone in the lower atmosphere where we breathe it is caused by UV radiation from the sun acting on smog and air pollutants especially on hot summer days.

Ozone at ground level is a harmful pollutant; in the stratosphere, it is a protective shield.

The ability of a substance to destroy ozone in the stratosphere is referred to as the ozone depletion potential (ODP).

Chlorine in refrigerants cause’s stratospheric ozone depletion.

The rise in the amount of chlorine measured in the stratosphere matches the rise in ozone-depleting emissions of CFC’s and HCFC’s over the same period.

According to the Roland-Molina theory, 100,000 ozone molecules are destroyed by each chlorine atom in the stratosphere.

When ozone depletion occurs, more UV radiation penetrates to the Earth’s surface.