6. Good ozone also
called(stratospheri
c ozone).occurs
naturally in the
upper
stratosphere
which is shield
human & animal
life from the suns
harmful UV rays
its called good
ozone. because it
protects animal &
Bad ozone is also called
tropospheric or ground
level ozone. Bad ozone
does not exist naturally.
Human actions cause
chemical reactions
between oxides & volatile
organic compounds(VOC).
Chemical reaction those
found in cars power plants
factory emissions in the
presence of sunlight(UV
light) is bad ozone, which
is contaminating the air. 18/04/2019
7. When volcanoes erupt. they produce massive clouds
of ash in the troposphere then they draft into
stratosphere
These ash contain high concentration of Bromine
Halogens & Chlorine ash can stay about to 2-5 years
in stratosphere within this period there are chemical
reaction that destroy the stratospheric ozone
molecules
Ozone destroying gases like hydrogen chloride are
already there
Volcanoes contribute 18-20% of chlorine entering the
atmosphere and human activities contribute 80-82%
18/04/2019
10. O3 depletion does not occur in warm parts of the world
The ozone hole is confined to the Antarctic region
Top atmospheric researchers conformed that ozone levels vary
by season & latitude.
In 1979 it was observed that there considerable ozone hole in the
upper latitudes. Arctic & Antarctica this hole is estimated to be
about the size of America.
In the winter temperatures drop below -78 c in the poles
Antarctica
The cloud form of ice, nitric acid, sulphuric acid mixture & active
cloud of CFC gas
In the spring temperatures begin to rise. Ice evaporates and
ozone layer starts to recover.
18/04/2019
11. Counteracting steps
Montreal protocol
Kyoto protocol (1986)- Demanded reducing CO2 and other green house gasses emission
Paris agreement (2015)
18/04/2019
