5. What is the ozone layer?
The ozone layer is a
layer of gas
consisting of O3
molecules, called
ozone, that forms
when free Oxygen
molecules bond to O2
molecules.
6. Where is the ozone layer?
The ozone layer is
mainly located within
the stratosphere.
Ozone gas also exists
in the troposphere and
at ground level.
8. Why ozone is important to life on
Earth?
The sun radiates its energy toward Earth.
One form of this energy is UltraViolet radiation, also known as
UV rays.
UV rays are relatively high energy waves that provide Earth with
the warmth it needs to support life.
9. The stratospheric ozone
layer completely stops
the penetration of UV-C
rays and eliminates
most of the UV-B rays.
Therefore, the ozone
layer protects life on
Earth from the harmful
effects of solar radiation
on a daily basis.
10. OZONE DEPLETION
➔ Ozone layer depletion, is simply the reduction
of the amount of ozone .
➔ There is widespread concern that the ozone
layer is deteriorating due to the release of CFC.
11. Ultra-Violet Radiation
UV rays penetrate
the Earth’s
atmosphere at 3
slightly different
wavelengths called
UV-A, UV-B, and
UV-C rays.
12. The Ozone Hole
Since the 1970’s the ozone hole has been increasing in
size over the Antarctic.
For the first time, in September of 2000, the ozone hole
became so large it actually left populated areas of
southern Chile fully exposed to the effects of the Sun’s UV
rays.
13. EFFECTS OF OZONE DEPLETION
1-GLOBAL WARMING1-GLOBAL WARMING
2-HUMAN HEALTH2-HUMAN HEALTH
3-crops3-crops
4-MARINE ECOSYSTEMS4-MARINE ECOSYSTEMS
14.
15. How does ozone depletion affect
global warming
As ozone levels in the stratosphere are depleted,
more solar radiation penetrates the Earth’s
atmosphere.
This affect results in an increase in solar radiation
reaching the Earth’s surface adding to an increase in
surface temperature.
In turn, global warming actually results in a
warming of the troposphere, but a cooling of the
stratosphere, hindering the ozone layer’s natural
chemistry for repairs.
19. EFFECT ON MARINE MARINE ECHO SYSTEM
● UV-B can penetrate clear water to a depth of
20 metres. .There is a recent evidence that
exposure to enhance UV-B is harmful to
phytoplankton,plankton and the larvae of
fish and shrimps
➢UV rays can reduce productivity
➢Damage DNA
24. How Human Destroy Ozone Layer?
Since 1928, CFC have been produced,
originally as nonflammable refrigerants for
use in refrigerators, and eventually for use in
fire extinguishers, dry cleaning agents etc..
As these CFCs have been released into the
atmosphere, the level of ozone in the
stratosphere has decreased.
CFCs have an estimated lifespan of more
than 100 years.
29.
After the discovery of ozone depletion in the late
1970’s, many countries agreed that something
must be done worldwide to stop ozone
depletion.
Vienna Convention in 1985 followed by the
Montreal Protocol in 1987.
Kyoto protocol -1997 in japan.
Protocol for ozone depletion