The document discusses ozone layer depletion and its impacts. It explains that ozone, a form of oxygen, protects the Earth from UV radiation. However, industrial emissions like chlorofluorocarbons released from refrigerants and aerosols are depleting the ozone layer. This depletion is most severe over the polar regions, where it forms ozone holes. Ozone layer depletion leads to increased UV radiation reaching the Earth's surface, which can harm animal and plant life and increase human health risks like skin cancer. International agreements like the Montreal Protocol have sought to regulate ozone-depleting substances to help protect the ozone layer.

1. Ozone Layer: Its Depletion and Impacts
Presented by,
Masud Rana Mondal
Assistant Professor
Department of Geography
Sailajananda Falguni Smrity Mahavidyalaya
Birbhum, West Bengal

2. Ozone (O3) is a isotope of Oxygen, a
molecule contains three atoms of Oxygen. .
Mostly concentrated in Stratosphere in
between 15 to 35 km. also it is called as
ozone layer.
Key information
 Its density varies seasonally and
geographically.
Dobsons is the measuring unit.
It protects us from harmful radiation.
This layer was discovered by
French physicist Charles Fabry and
Henri Buisson in the year of 1913

3. • In the Stratosphere protects us from
the UV radiationsGood ozone:
• It is a surface ozone, harmful for
animal, plants and human health
Bad ozone:

4. Ozone formation and depletion is a
balanced natural process.
After the industrial revolution, this
depletion is higher than formation
especially in the polar region that
called ‘ozone hole’.
The chemical components like
What is a Ozone hole?
The chemical components like
bromine or chlorine when coming in
contact with the ozone layer it
destroys ozone molecules faster than
its formation.
When the density of ozone is
reached bellow 200 Dobson its called
as the ozone hole.
According to many research, a
single chlorine atom can destroy
more than 100,000 ozone molecules.

5. The ozone layer depilation is associated with the number of factors.
Chlorofluorocarbons or CFCs are the main cause and realised from
refrigerator, air-conditioner, spray, solvents etc.
Reasons behind Ozone depletion
The nutrients components like NO2, NO, N2O also responsible the same.
Recently the researcher says that unrecognised rocket launcher is much more
of ozone depletion than CFC do.
Also, Halon, Carbon tetrachloride, Methyl chloroform etc are the ozone-
depleting substances.

6. Process of development of Ozone holeProcess of development of Ozone hole
Chlorine mainly responsible.
Chlorine Nitrate(CLONO2) and Hydrogen
Chloride (HCL) present in lower atmosphere.
In winter the temperature reached bellow -800C
in the polar region and due to polar air circular
cell, vortex created, air velocity reachedcell, vortex created, air velocity reached
300km/h in its middle.
Westerly wind carry huge water vapour, it
reached in stratosphere and formed PSC (Polar
Stratospheric Cloud)
CLONO2 and HCL reaction in PSC released CL2
CLONO2 + HCL CL2 + NHO3
In spring UV ray comes contract with CL2 and its destroy ozone
CL2 UV 2CL
CL + O3 O2 + CLO

7. What is polar vortex?
Polar vortex is a large area upper air low pressure area.
Developed in both the polar region.
This is mainly responsible for ozone hole in polar region.

9. WHY WE THINK ABOUT OZONE HOLE?
Ozone layer is like aOzone layer is like a
umbrella to protects usumbrella to protects us
Climate
from the harmful Sunfrom the harmful Sun
radiationradiation
Without ozone layer theWithout ozone layer the
earth might be a abundantearth might be a abundant
planet.planet.
Effects of
Ozone
Depletion
Animal
PlantsEcosystem
Human

10. Effects of ozone Depletion
ClimateClimate Global warming , flood and draught, rise of sea
level, acid rain etc.
AnimalAnimal Abnormal mutation, effects normal growth,
skin or eye cancerskin or eye cancer
PlantsPlants Reduce chlorophyll , reduce production,
effects on photosynthesis etc.
EcosystemEcosystem Destroy balanced ecosystem, effects on
environment,
Human bodyHuman body Sunburn, decrease immune system, skin
disease, quick ageing, skin and eye cancer.

11. International concernsInternational concerns
••Vienna conference (1985)Vienna conference (1985)
••Montreal protocol(1987)Montreal protocol(1987)
••London conference (1989)London conference (1989)
Chlorofluorocarbons or CFCs free
refrigerator, air-conditioner, spray,
solvents etc
The nutrients components like NO2,
What to do?What to do?
••London conference (1989)London conference (1989)
••Copenhagen conference (1992)Copenhagen conference (1992)
••Beijing protocol(1999)Beijing protocol(1999)
••Earth summit(1992)Earth summit(1992)
The nutrients components like NO2,
NO, N2O should use minimal.
Avoiding use pesticides.
Minimise use of vehicles.
Use eco friendly cleaning products
AwarenessAwareness