ozone layer

IMPORTANCE OF OZONE LAYER

Distribution in the stratosphere

The thickness of the ozone layer—that is, the total amount of ozone in a column overhead—varies by a large factor worldwide. The reasons for this latitude and seasonal dependence are involving atmospheric circulation patterns as well as solar intensity. Since stratospheric ozone is produced by solar UV radiation, the highest ozone levels over the tropics and the lowest polar regions.

Depletion of the ozone layer

If the ozone layer is depleted by human action, the effects on the planet could be catastrophic.

The suns rays are absorbed by the ozone in the stratosphere and don’t reach the Earth.

ozone is considered a dangerous pollutant and is one substance responsible for producing the greenhouse effect. The highest regions of the stratosphere contain about 90% of all ozone.

Stratospheric ozone filters out most of the sun's potentially harmful shortwave ultraviolet (UV) radiation. If this ozone becomes depleted, then more UV rays will reach the earth. Exposure to higher amounts of UV radiation could have serious impacts on human beings, animals and plants.

EFFECTS ON HUMAN HEALTH

Increase eye cataracts increase skin cancer suppression of

immune system increase eye burning

“The main cause of the ozone hole is the harmful compounds (CFCs) that are released into the atmosphere……..”

The "ozone hole" is a loss of stratospheric ozone in springtime over Antarctica.

Defined as the size of the region with total ozone below 220 Dobson units (DU).

The hole has been proven to be a result of human activities, release of huge amount of (CFCs) and ozone depleting substances.

Prior to 1979, total column ozone values over Antarctica never fell below 220.

PREVENTIVE MEASURES !

SOLUTIONS !Stop producing all ozone

depleting substances. CFC substitutes: HCFCs contain fewer chlorine

atoms. HFCs contain fluorine but no

chlorine. HCs useful in coolant and

insulating foam.

BY: SHIVANI BHARDWAJCLASS: Xth-B