Ozone depletion

k.Varun kumar

What is ozone?

Ozone is a tr iatomic form of oxygen Ozone is a tr iatomic form of oxygen found in earth’s upper and lower found in earth’s upper and lower atmosphere.atmosphere.The layer is a layer absorbs 97%-99% of The layer is a layer absorbs 97%-99% of the sun’s high frequency ultraviolet l ight, the sun’s high frequency ultraviolet l ight, which s potentially damaging to the which s potentially damaging to the forms on earthforms on earth

What is ozone layer?

The ozone layer is a layer in earth’s atmosphere which contains relatively high concentrations of ozone (O3)(O3) ..

The ozone layer, situated in the stratosphere about 15 to 30 km above the earth’s surface.

Ozone protects living organisms by absorbing harmful ultraviolet radiation (UVB) from the sun. The ozonelayer is being destroyed by CFCs and other substances.

Ozone depletion progressing globally expect in the tropical zone.

How hole is formed?

A combination of low temperatures and elevated chlorine and bromine concentrations are responsible for the destruction of ozone layer in the upper stratosphere thus forming a hole.

Also caused by the green house gases which are released by industries and vehicles

Meteorological mechanism

Moment of air from one place to another in the upper stratosphere.

Cold temperature in the upper atmosphere causes nitric cid to freeze into crystals forming wispy pink clouds.

Effects o plant growth

What are the effects of over exposure to UV rays ?

Skin cancer Eye damage such as cataracts Immune system damage Reduction in phytoplankton Damage to DNA in various life-forms ( this

has been observed in Antarctic ice-fish that lack pigments to shield them from ultra violet which they have never needed them before)

Cont….

Overexposure: increase risk of non-melanoma and malignant melanoma and malignant melanoma skin cancer

Possibly other things too that we don’t know about them

Skin cancer

phytoplankton

Phytoplankton: (phytoplankton uses carbon dioxide, releases oxygen, and converts minerals to a form that animals can use)

cataracts

Damage of immune system

Damage of DNA

How to protect ozone?

Minimize high altitude aircrafts (oxygen reduction and water vapour deposition)

Minimize rocket flight ( water vapour deposition)

Encourage growth of plants that produce that produce oxygen, discourage deforestation

Decrease/ control release of known ozone depleting chemicals (such as CFCs chlorine fatigue syndrome) where remotely possible. Subsidize production of safer alternatives where possible.

Actions taken individually

Don’t use the car so much Turn of the lights and the faucet when not in

use Use blankets to stay warm in the winter, wear

thinner clothes in the summer to stay cool instead of an A.C

Try to use products which are labeled “ozone-friendly”

Cont…

Vehicle air conditioning units should regularly be checked for leak

Ensure technicians repairing your refrigerator or air conditioner recover an recycle the old CFCs so they are not released into the atmosphere

Suggest school activities to increase awareness of the problem and to initiate local action

Minimize industrial refrigerators which releases chlorine

CFC-12 released in troposphere

Carried into stratosphere in the tropics by slow rising

circulation

CFC-12 photolyzed in stratosphere by solar UV,

releasing Cl

Cl catalytically destroys O3

Cl reacts with CH4 or NO2 to form non-reactive HCl or

ClONO2

Cl released by PSCs

How does chlorine get from our refrigerators to the Antarctic stratosphere?

Now you decide

Thank you