The document discusses the ozone layer and the effects of CFCs on it. It presents information about the sources of CFCs like cleaning agents and refrigerants. It also summarizes the effects of ozone layer depletion like increased UV radiation penetrating water and harming marine life. The document concludes with information about International Ozone Day celebrated every September 16th to raise awareness about protecting the ozone layer.

1. PRESENTED BY
CSE 2B, GROUP 3
• SAYANI SAHA (21)
• RISHABH VERMA (22)
• ABHISHEK JAISWAL (23)
• SHIWAM KUMAR PRASAD (24)
• AMAN REZA (25)
• SUBHANKAR BHANJA CHOWDHURY (27)
• ANIRBAN GHOSH (28)
• RAHUL GUPTA (29)
• SABYASACHI GANGULY (30)

7. NATURAL
PROTECTION

9. THE ”OZONE HOLE”
The diminishing ozone layer occurs when the
natural balance between the production and
destruction of stratospheric ozone is tilted in
favor of the destruction. Although natural
phenomena can cause temporary ozone loss,
chlorine and bromine released from man-
made compounds such as CFC are now
accepted as the main cause of this depletion.

11. PRESENT SITUATION
This image shows
ozone levels over
Antarctica as of 24th
July, 2018. The blue
regions signify less
ozone, while the
green and red areas
show higher ozone
presence

16. SOURCES OF CFC
Chlorofluorocarbons are released into the
atmosphere mainly from :
• Cleaning Agents
• Coolants used in refridgeration
• Packing material
• Air conditioners (ACs)
• Spray cans and aerosols

17. ACTION OF CFC MOLECULE

22. EFFECTS ON MARINE ECOSYSTEMS
UV-B can penetrate clear water up to a depth
of 20 metres. There is recent evidence that
exposure to enhanced UV-B is harmful to
phytoplankton, plankton and the larvae of fish
and shrimps. Even marine animals can get
affected negatively by it, which can be only
stopped by ozone layer.

23. EFFECTS ON ANIMALS AND MATERIALS

31. OZONE PRESERVTION DAY
International Day for the Preservation of Ozone
Layer is an annual observance. It is celebrated on
16th of September every year to spread awareness
and bring attention to the depletion of the ozone
layer. It also marks the anniversary of the signing of
the Montreal Protocol. This day is celebrated by
organizing seminars, speeches, and national as well
as international exhibitions worldwide.

32. OZONE DAY CELEBRATIONS IN INDIA