Acid rain is caused by sulfur and nitrogen oxides dissolving in rainwater to form acids that harm both the environment and human health. It damages forests, crops, aquatic species and infrastructure. The main causes are fossil fuel combustion and industrial emissions. To reduce acid rain, countries have implemented regulations limiting sulfur dioxide and nitrogen oxide emissions from power plants and vehicles. The ozone layer protects the Earth from ultraviolet radiation but was being depleted by chlorofluorocarbons (CFCs). The Montreal Protocol phased out CFCs to allow the ozone layer to recover. Climate change poses a challenge because it is a global problem requiring cooperation between countries to reduce greenhouse gas emissions.

1. PREPARED BY
Karm Balar
Global Environmental Issues

2. 7.32 Environmental Politics 2
Acid Rain
Ozone Layer Depletion
Climate Change
Biodiversity Loss
Ocean Exhaustion
Content

3. ACID RAIN

5. WHAT IS ACID RAIN ?

7. When pH of the rain water is less than 5.6, then
the rain is called ACID RAIN.
It is due to mixing of atmospheric CO2 in rain
water.
CO2 + H2O -----> H2CO3(Carbonic acid)
Some countries like
Europe,Netherland,sweden,USA experience
acid rain of pH 5-2.2.
It is observed in india,cities like kanpur and
mumbai.

8. Main cause of the
ACID RAIN
It due to dissolution of oxides of Nitrogen and
Sulphur present in the atmosphere which forms
nitric acid(HNO3) and Sulphuric acid(H2SO4)
1. 2 SO2 + O2 ---> 2SO3
SO3 + H2O ---> H2SO4(Sulphuric acid )
2. 2NO + O2 ----> 2NO2
4NO2 + 2H2O + O2 ----> 4 HNO3 (Nitric acid)
3. HCl gas HCl (Nitric acid)

10. H2SO4
60-70%
HNO3
30-40%
HCl
Very
small
ACID RAIN
CONTRIBUTION

11. CAUSES OF ACID RAIN

12. Dissolution of SO2 and NO2 formed by
burning of fossil fuel .
Dissolution of oxides of sulphur and
nitrogen emitted from automobile exhaust
and chimneys of smelting industries.
Industrial plant using sulphuric acid and
nitric acid.

13. EFFECTS OF ACID RAIN

15. HUMAN HEALTH
Skin irritation and aggravation of respiratory diseases.
AQUATIC LIFE
Acidification of lakes and streams.
In Norway and Swedan, does not contain fish.
VEGETATION
Decolourise of leaves and
reduction of chlorophyll content of plants.
WATER RESOURCES
Both surface and under ground sources get affected.
water treatment cost increases
water storage structures are damaged
STRUCTURES & PROPERTY
It affect marble and limestone of property
taj mahal is turning from white to yellow
SOIL pH
Low pH diminishes the bacterial activity in soil leads to
less nutrient fixation
leaching out of Aluminium at pH conditions
ECOSYSTEM
Break the food chain and food web and reduce bio-
diversity.

17. Decreasing the emissions of SO2 and NO2 .
Adopting energy conservation method.
Utilizing non-polluting energy sources.
Treating acidified lakes and soil with lime .
Adopting suitable SO2 reducing equipment in
industries and thermal power plants.
Use of natural gas instead of high-sulphur coal
for producing electricity.
Considering nuclear energy as an option for the
future fuel.

18. Ozone Depletion

19. Importance of the ozone layer
Near ground level (troposphere) - pollution
Form photochemical smog and acid rain
In the stratosphere (15 - 50 km) - ozone
layer screen out harmful Ultra-violet
radiation from the sun.

21. Our atmosphere
 Troposphere:
- The lowest layer (about 15 km from the ground)
- Contains normal air composed of N2, O2, water vapour, CO2, etc.
- Temperature decreases with altitude
 Stratosphere:
- Above the troposphere
- Temperature increases with altitude
- Contains a lot of ozone (ozone layer):
• Found in the stratosphere between 10 - 50km above the ground
• Protects us from the harmful effects of UV of certain wavelengths
• Decrease in ozone concentration  Increase in UV-B radiation
reaching the earth surface

22. Formation of ozone layer
O2+ sunlight  O + O
O + O2  O3

23. Ozone formation [2]
Ozone (O3)
Chemically forms when UV hits on stratosphere
Oxygen molecules dissociate into atomic oxygen
 Atomic oxygen quickly combines with other oxygen molecules
to form ozone
O2 O + O
O + O2 O3

24. Ozone formation [3]
Ozone (O3)
A pollutant on ground level
– A component of photochemical smog
Important for our survival
– Absorbs some of the potentially harmful UV radiation
which can cause skin cancer and damage to vegetation
Split and regenerate repeatedly
Highest concentration in the upper atmosphere
Concentration decreases at lower altitudes

25. Ozone formation [1]
Ozone (O3
)
Made up of three oxygen atoms
Occurs naturally as a layer in the stratosphere
The layer is thinnest around the equator and the
concentration increases towards the poles
The amount of ozone above a point on the earth’s
surface is measured in Dobson units (DU)
– ~ 260 DU near the Tropics
– higher elsewhere

26. What is CFCs? [1]
Chlorofluorocarbons (CFCs)
Composed of elements chlorine, fluorine, and
carbon
Developed in 1930 by DuPont
CFCs were welcomed by industries:
– Low toxicity
– Chemical stability
– Cheap
Usage:
– As refrigerants
– As blowing agents
– For making flexible foam
– As cleaning agents
– As propellants

27. Present Situation
Stratospheric ozone over Antarctica:
– Has been depleted over the last 15 years
– The ozone hole:
enlarging
large enough to cover most of the North America
would take at least 50 years to restore

29. Destruction of ozone layer
Chlorine atoms from CFCs attack the ozone,
taking away ozone and forming chlorine
monoxide (ClO).
O3 + Cl  O2+ ClO
Chlorine monoxide then combines with
another oxygen atom to form a new oxygen
molecule and a chlorine atom.
ClO + O  Cl + O2
Thechlorineatomisfreetodestroyupto100,000ozone molecules

30. Causes of ozone depletion
Details are not fully understood
Catalyzed by halocarbons (carbon compounds
containing fluorine, chlorine, bromine and iodine)
– Examples: CFCs and ClONO2
Halogen atoms catalyze ozone layer depletion by
destroying ozone molecules and forming oxygen
molecules.
Much more serious in Antarctica than other regions
on the planet.

31. Consequences of less ozone
Because CFCs has long life span and very
stable, it continuous to attack the ozone
layer and more UV-B reach our earth.

32. Impacts on human health
Skin Cancer
Cataracts and Other Eye Damages
Suppression of Immunity

33. The Ozone Hole
The ozone hole
is the region over
Antarctica with
total ozone 220
Dobson Units or
lower.

34. Remedies of Ozone Depletion
Ban the use of CFCs as aerosol propellants
The Vienna Convention on the Protection of the
Ozone Layer in 1985
– Governments committed themselves to protect the ozone
layer and to co-operate with each other to improve
understanding of ozone crisis.
The Montreal Protocol on Substances that deplete
the Ozone Layer
– Adopted by Governments in 1987
– Aims to reduce and eventually eliminate the emissions of
man-made ozone-depleting substances.

35. 7.32 Environmental Politics 35
Environmental policy is about what government does
and does not do to address environmental problems
Environmental politics is the clash of values &
interests that occurs in the course of formulating and
implementing policy
What does this suggest about international
environmental politics and policy?
International Environmental Politics

36. 7.32 Environmental Politics 36
Global in Scale
Long-term in Scope
Significant Scientific Uncertainty
Large Economic Stakes
Complex Institutional Management
“Third Generation” Issues

37. 7.32 Environmental Politics 37
Sovereignty
No Supra-National Authority
– U.N.
– World Court
WHY NOT IMPOSE INTERNATIONAL
ENVIRONMENTAL REGULATIONS?

38. 7.32 Environmental Politics 38
Why was it possible to construct an international
regime to respond to Ozone Depletion
– Immediate scope and tangibility of the problem
– Small set of CFC producers
Industry interested in product change
– Relatively Low Cost to Industry
No net economic impact on states
– Developed-Developing states rift healed by funding
Ozone, CFCs, and Montreal

39. 7.32 Environmental Politics 39
Global Climate Fluctuations

40. 7.32 Environmental Politics 40
Treaty Text
GHG Emissions Reductions
– 1990 target year
– Industrial Countries = 5% reduction from 1990
emissions levels by 2012
US = 7%
European Union = 8%
Japan = 6%
Emissions trading allowed
– Industrializing Countries = voluntary reductions
Kyoto Treaty

41. 7.32 Environmental Politics 41
90% of US GHG emissions = fossil fuel
combustion
US reduction strategy must involve
– Energy efficiency/conservation
– Removing subsides from fossil fuel
extraction/production
(~ $100 billion/year)
– Develop alternative energy sources
US GHG “Problem”

42. 7.32 Environmental Politics 42
Convincing the government there is a problem
Devising an effective course of action
Getting other governments to do likewise
Policy Problem

43. 7.32 Environmental Politics 43
Bush CO2 PlanCO2MTper$million
Year

44. 7.32 Environmental Politics 44
Bush CO2 PlanCO2MTper$million
Year

45. 7.32 Environmental Politics 45
Bush CO2 Plan
Year
CO2MT
Emissions

46. 7.32 Environmental Politics 46
Continental-Scale Ecosystem Destruction
– Human Population Growth
– Economic Development
Mining, forestry, agriculture
Ebola virus killing off African primates
Climate Change
Biodiversity Loss

47. 7.32 Environmental Politics 47
Consumptive Use
Bio-Homogenization
– Economic Globalization
– Alien Invasions
Fungus decimating amphibian populations
West Nile Virus decimating bird populations
– Plus dozens of other species
Sudden Oak Death Syndrome
Wooly Adelgid
Biodiversity Loss

48. 7.32 Environmental Politics 48
Consumption
– Collapsing Fish Populations
– “collateral damage
Leatherback turtles
Pollution
– Eutrophication
Dying Coral reefs
– Toxins, Viruses, Bacteria
Sea otter decline
Habitat destruction
– Bottom trawling
– Coastal wetlands
Ocean Exhaustion

49. Thank you