Climate change Biodiversity Impacts Global warming Green house effects Ozone hole CFC's Biological diversity Bromine Food web Green house gases Water vapour Infrared radiation Fossil fuels burning Industrial pollution

1. CLIMATE CHANGE AND ITS
IMPACT ON BIODIVERSITY
PRESENTATION BY
P. KATHIRAVAN
M.Sc.,(Agri) Genetics and Plant Breeding

2. • CLIMATE CHANGE
• “Climate change” means a change of climate which is attributed
directly or indirectly to human activity that alters the composition
of the global atmosphere and which is in addition to natural climate
variability observed over comparable time periods.
• • However, when today people talk about ‘climate change’, they
mean the changes in climate over the last 100 years which is caused
predominantly by human activity.

3. • REASON FOR CLIMATE CHANGE
GLOBAL WARMING
• “Global warming is an average increase in the temperature of the
atmosphere near the Earth’s surface and in the troposphere, which
can contribute to changes in global climate patterns.
• It is caused by both natural and human induced.
• Mainly due to increased emissions of greenhouse gases from
human activities .

4. • Global Warming - Impacts
• Rise in Sea level
• Changes in rainfall patterns.
• Melting of the ice caps.
• Melting of glaciers.
• Spread of disease (like malaria, etc).
• Bleaching of Coral Reefs.
• Loss of Plankton due to warming of seas.

5. REASON FOR GLOBAL WARMING
• 1 .GREEN HOUSE EFFECT
• The greenhouse effect is a naturally occurring phenomenon that
blankets the earth lower atmosphere and warms it maintaining the
temperature suitable for living things to survive.
• Water vapour and greenhouse gases warms the Earth.
• List of Green house gases
SO2, NO2, CO2

6. Incoming Energy
• The Sun emits energy that is transmitted to Earths Atmosphere.
Absorption
• About 30% of the Sun's energy is reflected directly back into space
by the atmosphere. The rest of the Sun's energy is absorbed into
the Earth's system (70%) .
Emission
• The Earth re-emits energy back into the atmosphere
• The energy is emitted in the form of infrared radiation, at
wavelengths longer than the incoming solar energy.

8. • 2. HUMAN ACTIVITIES
• The top activities that lead to the human causes of climate change
include:
• The burning of fossil fuels, such as coal, oil, and carbon
dioxide (driving your car, heating your home, etc.)
• Industrial processes (pollution from factories, product production,
etc.)
• Agriculture (conversion of land, etc.)
• Conversion of land for forestry.

9. • OZONE AND OZONE DEPLETION
• Ozone is found in two different layers of the atmosphere.
• Ozone in the troposphere is "bad" because it dirties the air and
helps to form smog, which is not good to breathe.
• Ozone in the stratosphere is "good" because it protects life on Earth
by absorbing some of the sun's harmful Ultra Violet (UV) rays
• Decrease in the concentration of ozone in a particular region of the
atmosphere of ozone hole.

10. example : Antarctic ozone hole which has only about 50 percent of
the ozone that originally occurred there.
SOURCES
• Chlorofluorocarbons (CFCs):
• CFCs molecules are made up of chlorine, fluorine and carbon.
They are used as refrigerants (66%):
• Propellants in aerosol sprays,
• foaming agents in plastic manufacturing (30%),
• fire extinguishing agents,

11. • solvents for cleaning electronic and
• metallic components,
• freezing foods .
• It has properties like non- corrosiveness, non-in flammability, low
toxicity and chemical stability, etc.
• The residence time of CFCs in the atmosphere estimated to be
between 40 and 150 years.
• N2O
• Nitrous oxide (N2O) is released from nitrification of ammonia under
aerobic conditions.
• This N2O can gradually reach the middle of the stratosphere, where

12. • it is photolytically destroyed to yield nitric oxide which in turn
destroys ozone.
BROMINE
 Bromine containing compounds called halons and HBFCs.
i.e hydrobromo fluorocarbons [both used in fire extinguishers
and methyl bromide (a widely used pesticide).
Each bromine atom destroys hundred times of more ozone
molecules than what a chlorine atom does.

13. • BIOLOGICAL DIVERSITY
• Biological diversity refers to the variant amongst dwelling
organisms and the ecological complexes of which they are a part.

14. TYPES
1 .Genetic diversity
– Variation in genes within a particular species.
– It is the total number of genetic characteristics in the genetic
makeup of a species.
2. Species diversity:
– It refers to the variety of living organisms on earth.
– Species differ from one another, markedly in their genetic
makeup, do not inter-breed in nature.
– It is the ratio of one species population over total number of
organisms across all species in the given biome.

15. 3. Ecosystem / Community diversity:
– This refers to the different types of habitats. A habitat is the
cumulative factor of the climate, vegetation and geography of a
region.
Biodiversity and Food Web
• The building blocks of plants, animals and humans are identical, and
are made of the four elements - carbon, oxygen, nitrogen and
hydrogen
• The chain that links consumers to producers is called the food chain
or web of life.

16. Impact of Climate Change on Biodiversity
• The environmental changes being driven by climate change are
disturbing natural habitats and species in ways that are still only
becoming clear.
• Rising temperatures are affecting biodiversity, while changing
rainfall patterns, extreme weather events, and ocean acidification are
putting pressure on species already threatened by other human
activities.
• Rising temperatures in the oceans affect marine organisms.

17. • Rising global temperatures also have the potential to alter
ecosystems over longer periods by changing what can grow and live
within them.
• Number / proportion of species threatened by declining due to
climate change. Fraction of biodiversity indicator (e.g. RLI, LPI,
EBV) change attributable to climate change.