Global environmental degradation

05 June is the world environment day

 Human impact
 Signs of environmental crises.
 Global environmental crises
 Causes of Environmental
degradation
 Drivers of environmental
degradation
 Impacts of environmental
pollution
 Solving environmental
problems.

The term "environment" means the
surroundings of an organism.
The total environment of an organism is
the sum total of the biotic and abiotic
environments.

Natural environment is of
crucial importance for
social and economic life.

Humans are one part
of a complex world
ecosystem.
Humans dominate the
planet and all its life.
Human actions have
a profound impact on
the environment

Environmental Humans Natural
degradation hazards

Earth

In many parts of the world :

Forests are shrinking Water tables are falling
Deserts are expanding Rivers are running dry
Soils are eroding Fisheries are collapsing
Rangelands are Coral reefs are
deteriorating disappearing
The lower atmosphere is Life forms are vanishing
warming Pollutants and waste are
Glaciers are melting rising
Sea levels are rising Tropical diseases are
Storms are destructive emerging

Disaster Source/place Month & year No. of victims
Minamata mercury Chisso chemical 1950s 2,265 deaths
poisoning Corporation, Japan
Seveso disaster - Chemical July 193 Human deaths
Dioxin cloud manufacturing 1976 3,300 animal deaths
Industry, Italy
Bhopal gas leak Union Carbide December 35,000 deaths
pesticide plant 1984
.Bhopal, India
Chernobyl nuclear Nuclear power plant April 4000 cancer deaths
disaster Ukraine 1986
Exxon Valdez Oil tanker accident in March 250,000 sea birds
Oil spill-Prince William Alaska coast 1989 2800 sea otters
sound 300 seals- deaths

Super cyclone Orissa ,India October 10,000 deaths
1999
Asian Tsunami Indian ocean December 227,898 deaths
earthquake- 2004
11 countries

- population - density
- exploitation - resources
- farming - agriculture
- logging - forests

- fishing - oceans
- tapping – ground water

-grazing - grass lands

 Pollution of ecosphere,
 Global warming
 Deforestation
 Loss of ecosystems
 Loss of biodiversity
 None of the above
occur alone, each
change triggers
another

 Environmental impact
= population size X per
capita consumption X
pollution and resource
use per unit of
Environmental
impact refers to consumption.
the alteration of
the natural
environment by
human activity

 Professor Paul Ehrlich is a
biologist and author of the
best-selling book ‘The
Population Bomb(1968)’.
 Paul Ehrlich is one of the world's
leading experts on population.
 He is renowned for his role in
helping the world to think
about resource scarcity and
the impact of an ever-
increasing population on
demand for natural resources.

Environmental
impact(I) = population(P) x consumption(C)
Or I = PX C

Environmental impact formula
I=PAT
Where I= environmental impact
P=the number of people
A= affluence=average resource use
per person
T= technology=environmental effects
of technology

 In the early 1970s, ecologist Barry
Commoner published a book ‘The
Closing Circle’.
 He insisted that the rapid growth of
industry and technology have persistent
effect on all forms of life.
 Based on Barry Commoner's
warnings, Time magazine warned in its
cover story on Commoner (February 2,
1970), "the price of pollution could be
the death of man."
Barry Commoner’s four laws of ecology :
 Everything is connected to everything else.
 Everything must go somewhere.
 Nature knows best.
 There is no such thing as a free lunch.

 Yoichi Kaya (1990)-  Global CO2 emissions =
Japanese energy (population)x(GDP/population)
x(energy use /GDP)x (carbon
economist emission/energy use).
 Human impact on environment
can be calculated through 4
factors
1. Population
2. Gross domestic product
/person
3. Energy use / unit of GDP
4. Carbon emissions/ energy unit.

Population growth

Human Environmental
impact crisis

Pe
rc
ap
it ac
on

y
og
su
ol
m pti
ch
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o n
Te

 Human population growth is the
number one threat to the world's
environment.
 The environmental impact of
human activity is a function of
population, consumption and
technology.

 The world’s population presently
grows by about 250,000 people per
day.

 The human population is
exceeding the carrying capacity
of our planet.

 Increasing human population and
industrial activities have led to
problems associated with the
pollution of air, water, and soil.

 a high birth rate
 a relatively low death rate due to
advances in medicine and
technology.
 more agricultural production,
 restrictions on women’s rights, and
 prohibitions on birth control .

 According to the law of population
growth, no population can continue to
grow exponentially forever.

 Earth has finite resources.
 Its ability to sustain the growing
population is finite.
 Its ability to provide food and
energy is finite.
 Industrialized nations consume
more resources per capita

 Global resource consumption is rising
rapidly.
 This consumption is driven by
population growth and rising wealth.
 As a result this ever-increasing
consumption, emissions and wastes
pollute the earth and destroy the
ecosystems.

 The burning of fossil fuels has almost quintupled
since 1950.
 The consumption of freshwater has almost doubled
since 1960.
 The consumption of cereals has more than
doubled in the last 30 years.
 World meat consumption has tripled since 1961.
 The consumption of fish and fishery products has
increased more than five fold since 1950.

 Improved quality of life
 Greater economic growth
 Rapid and bulk production of goods
 Better transportation
 faster communication
 Comfortable housing
 Enjoyable recreation

 Pollution of life support systems
 Degradation of natural habitats
 Global warming & climate changes
 Depletion of natural resources
 Impact of industrial agriculture
 Toxic contamination
 Depletion of ozone layer

 Deforestation is the removal trees
from a forest and converting the land
for other use.
 Tropical rainforests are disappearing
at an alarming rate.
 Destruction of forest leads to
extinction of species

 The gradual transformation of
healthy fertile land into a desert.
 Desertification is usually caused
by climate change or by
destructive use of land .

 Air pollution is made up of a mixture of
gases and particles that have been
released into the atmosphere by man-
made processes..
 We breathe about 2 gallons of air every
minute.
 A typical human lifespan can be reduced
by 1-2 years from inhaling polluted air.

 Global warming is a gradual rise
of the earth’s temperature.
 It is a function of the greenhouse
effect.
 There is a rise in global mean
surface temperature by 4 -6
degrees C..

Non-greenhouse Greenhouse gases
gases (GHGs)
 Carbon dioxide (CO2)- burning
 Nitrogen,N2 fossil fuels and wood.
 Nitrous oxide (NO2)-
 Oxygen,O2 fertilizer use and decomposition
of animal wastes.
 Argon,Ar  Methane (CH4)- sediments,
swamps, landfills, and in flooded
rice paddies.
 Chlorofluorocarbons (CFCs)-
Freon (a refrigerant)
 Halons, such as halocarbons- fire
extinguishers.
 Water vapor -clouds reradiate
heat back to Earth.

Combustion of fossil fuels

Volcanic eruptions Land use changes &
deforestation

Sources of
global Power generation &
oceans
carbon dioxide transport
emissions

Breathing & Industrial processes
Decomposition of
plants and animals
Forest and wild fires

650-
315ppm 372ppm 700ppm

year 1750 1993 2008
1958 2002 2100

280 ppm 360ppm 384ppm

 The atmospheric carbon dioxide is the
principal climate –altering gas.
 Carbon dioxide absorb heat
radiation( infrared) from the sun and emit
towards the earth.
 Elevated CO2 means more heat will be
radiated.
 Water vapor act as an amplifier of warming.

 Greenhouse gases have been essential to
the survival life on planet earth.
 They trap heat and cause the earth to
warm.
 Human activities alter the proportion of
GHGs in the atmosphere.
 They add more GHGs and induce more
heat trapping by the atmosphere.

Gas formula Contribution, %

Water vapor H2O 36-72 %

Carbon dioxide CO2 9-26%

Methane CH4 4 – 9%

Ozone O3 3 – 7%

Regions World population,% Responsibility for
Global warming, %

The West 15 46

Central/Eastern 7 19
Europe

Third world 78 35

Source: New International, April 1990,

Chemical Conc. In Atmospheric GWP
Greenhouse
formula 2005 life , years
gas

Carbon CO2 379ppm variable 1
dioxide

Methane CH4 1774ppb 12 21

Nitrous N2O 319ppb 114 310
oxide

Source % contribution

Transport industry 64

Forest fires 16.9

Agricultural 7.2
burning
Industrial processes 7.6
(Iron,steel, petroleum,paper)
Miscellaneous 16.9

1. Frequent temperature extremes ( killer heat
waves).
2. Changing rainfall patterns.
3. Rise in sea levels.
4. Frequent storms and coastal flooding
5. Drought
6. Air pollution made worse by warming.
7. Asthma, bronchitis, emphysema complications
8. Expansion of Deserts.
9. Unable to contain spread of infectious
diseases

Sun light☼

 The term smog was derived from the words
’fog’ and ‘smoke’. The term was first used in
1905 by H.A. Des Voeux.
 VOCs and NOx react in presence of sunlight to
produce ozone and PAN (peroxy acetyl
nitrate)

Los Angeles smog London smog

Photochemical smog Sulfurous smog

Summer smog (July1973) Winter smog (Decem 1952)

Petroleum combustion Coal combustion

Automobile exhaust Industrial sources

Light-brownish in colour Yellow-black in colour

Secondary pollutants – H2So4, O3, PAN, Organics, acids
sulfate aerosols
Respiratory distress Lung disease

Ozone (O3)

Stratospheric ozone Tropospheric ozone
-upper atmosphere (ground –level ozone)
-good ozone -lower atmosphere
-bad ozone

Absorb UV-B rays Greenhouse effect
Global warming
Prevent skin cancer
Cataract etc. Global
climate change

Ozone depletion results in ‘ozone
hole’ in upper atmosphere.
During the 1980s, scientists
discovered a "hole" in the ozone
over Antarctica.

 Breathing O3 affects both the respiratory and nervous systems,
resulting in respiratory distress, headache, and exhaustion.
 Ozone is damaging to plants, resulting in leaf mottling and
reduced growth.
 Hazards of UV radiation include skin cancer and cataracts and
depression of the immune system.
 Each 1% drop in ozone is thought to increase human skin cancer
rates by 4-6%.

 Acid rain is the term used to describe
polluted rainfall (acid pollution).
 Acid rain is directly linked air pollution.
 Acid rain is defined as the precipitation
with pH less than 5.6.
 The phenomenon of Acid rain is
becoming a global environmental
problem.

 Acid rain is mainly due
to the reaction of water
vapor with sulfur dioxide
and the oxides of
nitrogen.
 Acid rain often has a pH
as low as 2.4
 2SO2 + O2 + 2H2O →
2H2SO4
 4NO2 + O2 + 2H2O →
HNO3

Sterilization of lakes and forests.
Reducing the populations of small
invertebrates and decomposers.
Reducing agricultural yields.
Causing structural damage by corroding
marble, metal, and stonework.
Leaching heavy metals from the soil into
drinking-water supplies.
Increases in lung cancer and colon
cancer.

 Loss of soil quality and
productive capacity
 Loss of organic matter,
 Reduction of vegetative
cover
 Loss of soil life

 Degradation results in soil compaction
and erosion, a reduction in water
holding capacity and increased
salinization.
 Soil is getting thinner , “tired” and “worn
out”.

 Land pollution is caused by poor
agricultural practices, usage of
pesticides, mining for coal and
minerals, and dumping industrial
and urban wastes.

 Approx. 700 million people in 43 countries
suffer as a result of water scarcity.
 Nearly 1 billion people lack safe drinking
water.
 Half of the world’s 500 major rivers are
polluted.
 75% of India’s lakes and rivers are too
polluted for safe use.

 Water shortage - levels of available water
do not meet minimum requirements.
 Water scarcity – the relationship between
demand for water and its availability.
 Water stress – decline in water quality.
 Water security – access to adequate
quantity and safe quality.

Toxicity- acute / chronic –
damages aquatic / human life
Changes in Sub-lethal toxicity
Water chemistry Endocrine disruption /
Changes in biodiversity

Effects of water Acidity/alkalinity
Eutrophication pollution Changes pH regime

Altered water Spread of microbial
temperature diseases
Deoxygenation-
Lack of O2 in water

Biodiversity is our living wealth

 Biodiversity is a global resource.
 It is a vital part of the earth’s life-support
system.
 Biodiversity is the mainstay of agriculture ,
forests and fisheries.
 Biodiversity today is the result of 3.5
billion years of evolution.

Biodiversity is under threat
 Biodiversity is under threat
globally, nationally and locally.
 There are TWO main causes of
Biodiversity loss:
1.Destruction of species
2.Destruction of habitats

 Assessment
 Risk analysis
 Public
education
 Political action
 Follow-through

 The gathering of
information
 Performing
experiments
 Make predictions

 Use the available
information to predict the
consequences of
environmental degradation.
 Evaluate the potential to
solve the environmental
problems.

 Inform the public.
 Explain probable
costs and results.
 Present alternative
actions.

 The public, through
officials, selects and
implements a course
of action.

 Prevent pollution.
 Reduce waste.
 Try composting of biodegradable garbage.
 Use water, energy and natural resources
efficiently.
 Maintain the diversity of life.
 Protect the world's natural, cultural and
indigenous heritage.
 Support environmental education.
 Support local action and community
participation.

 Dr.B.Victor is a highly experienced professor,
recently retired from the reputed educational
institution- St. Xavier’ s College,
Palayamkottai, India-627001.
 He was the dean of sciences and assistant
controller of examinations.
 He has more than 32 years of teaching and
research experience
 He has taught a diversity of courses and
guided 12 Ph.D scholars.
 comments to : bonfiliusvictor@gmail.com

Global environmental degradation

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