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ANTHROPOGENIC IMPACT ON CLIMATE CHANGE

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Climate change- long term change in statistical distribution of weather patterns over periods of time that range from decades to millions of years and more generally known as Global warming or Anthropogenic Global warming – PowerPoint PPT presentation

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Title: ANTHROPOGENIC IMPACT ON CLIMATE CHANGE


1
ANTHROPOGENIC IMPACT ON CLIMATE CHANGE
2
WHAT IS THE MEANING OF TERM ANTHROPOGENIC ?
  • Activities that are carried by human beings
  • British ecologist Arthur Tansley (1936) , used
    this term first time in English in reference to
    Human Influences on climax plant communities
  • The term was first time used by Russian Geologist
    A.P. Pavlov in 1922 in reference to the
    ANTHROPOGENIC STYSTEM

3
CLIMATE AND CLIMATE CHANGE
  • Climate is a measure of the average pattern of
    variation in temperature, humidity, atmospheric
    pressure, wind, precipitation, atmospheric
    particle count and other meteorological variables
    in a given region over long periods of time.
  • Climate change- long term change in statistical
    distribution of weather patterns over periods of
    time that range from decades to millions of years
    and more generally known as Global warming or
    Anthropogenic Global warming

4
SOLAR RADIATION AND CLIMATE
  • Climates are dependent on solar radiation cycle
  • Solar radiation derives atmosphere and
    hydrosphere circulation that shifts air masses ,
    water and energy around the world
  • Amount of radiation cooler warmer climate

5
Earths Temperature
6
EARTHS TEMPERATURE
7
HUMAN IMPACT ON CLIMATE CHANGE
  • History ice core and record of atmospheric
    greenhouse gas concentration of last 10,000 years
    to understood it
  • - CO2 conc. Fluctuations, high during warmer
    climate and low during cooler climate
  • Expected trend of decreasing CO2 conc. Starting
    about 10,000 years ago that accompanies cooling
    global climate as predicted by solar radiation
    cycle
  • But conc. of CO2 started to increase

8
INCREASE OF CO2 CONCENTRATION
  • So, something new influences and different from
    the factors that had controlled it during warm
    and cold cycles of the past few hundred thousands
    of years

9
TRENDS IN CH4 CONCENTRATION
  • Same type of concentration change was apparent in
    ice core Methane data
  • Shift from decreasing to increasing concentration
    took place 5000 years ago
  • New influence on green house gas concentration
    that changed the natural shifts appear to have
    HUMANS

10
  • Paleoclimatologist William F. Ruddiman hypothesis
    set forth in his book Plows, Plagues And
    Petroleum.
  • Anthropocene , it as the era in which humans
    first began to alter the earths climate and ecosy
    stems
  • He emphasized that this change is due to human
    activities, as they started farming about 8000
    years ago
  • -significant deforestation began about 8000
    years
  • -people progressed from stone age to iron age,
    population and agriculture expanded
  • -survey completed in England in 1809 A.D.,
    William revealed that 85 countryside was already
    deforested about 700 years before the industrial
    revolution
  • -deforestation increased atmospheric CO2 conc.
    From 260 ppm. (7000 years ago) to 280-285 ppm
    (200 years ago)

11
WHAT ABOUT METHANE ?
  • Started increasing instead of naturally
    decreasing about 5000 years ago
  • Ruddiman purposes that wet rice farming in
    South-East Asia may have been the cause, as
    methane generated by plant decay in wetlands
  • -rice paddies are tremendous methane generators
  • -emissions from livestock, biomass burning

12
INITIATION OF CLIMATE CHANGE
  • In preindustrial-era increase in atmospheric
    green house gases that date from starting of
    farming may have prevented ICE AGE conditions
    from developing from earth
  • -increase in conc. of CO2 and CH4 to create
    warming of 2C, just enough to keep Northern ice
    sheets from growing

13
EVIDENCE FOR DRAMATIC REVERSALS IN GENERAL TRENDS
  • Occur between 1100 and 1800 A.D.
  • Proposal of Ruddiman, people had hard time during
    this periods like by
  • -bubonic plague, small pox, typhus and cholera
    killed millions of peoples
  • -small pox killed 80-90 of indigenous peoples
    of America (50 million peoples)
  • -rendering of increase of green house gases
  • -reversal effect on conversion of forest land to
    farmland
  • -decreasing of atmospheric concentrations of
    GHGs, leading to global cooling

14
LITTLE ICE AGE (COOLER CLIMATE)
  • Earths climate was teetering on the edge between
    warming and cooling
  • Lower conc. of CO2 sent it on its way toward a
    glacial period
  • Time between 1250 and 1850 A.D. has become ,known
    as Little Ice Age
  • During this period alpine glaciers expanded
  • Expansion of Buffin Island is evidenced by
    surrounding area of dead lichen

15
Buffin island
  • Baffin Island, in the Canadian
  • territory of Nunavut, is the largest
  • island in Canada and the fifth largest
  • island in the world
  • Lichen are scruffy combinations
  • of fungi and photosynthetic
  • bacteria that grow on tundra and rock surfaces
  • They can handle long cold winters but they need
    at least some periods of summer sunlight for
    survive
  • - but lichen in Buffin island are dead, mean
    long time covered by snow during little ice age
  • -in mid 1800 A.D. Ended little ice age when the
    industrial revolution and fossil fuel burning got
    into full swing
  • -today Buffin island is rapidly melting and
    retreating

16
  • Starting of current episode of GLOBAL WARMING
  • The very recent shift warmer to warmer climate is
    taken as CLIMATE CHANGE which is a focus of
    Scientific Research and international
    Environ-mental Policy

17
GREEN HOUSE GASES
  • In modern-era climate change is generally
    reflected by GLOBAL WARMING which caused by
    green house gases that are continuously added by
    human activities that are linked with human
    dominant ecosystems i.e. Urban- techno-ecosystem
    and agro-ecosystem.
  • Major green house gases are carbon dioxide,
    methane, nitrous oxide, ozone, CFCs, sulphur
    hexafluoride and Perfluorocarbon.

18
GREEN HOUSE GASES AND HUMAN ACTIVITIES
  • I Increase of Carbon dioxide (CO2) conc.
  • -deforestation for farmland (CO2 consumers)
  • -burning of fossil fuels ( 1kg of FF release 3kg
    of CO2)
  • -animal husbandry (increased respiration rate)
  • -industrial effluents( hot water and other
    chemicals, effect ocean flora and warming leads
    to reduction of capacity of sinks)
  • -conc. Increasing rate is 2.0 ppm in the
    2000-2009s
  • -has risen to 392 ppm (parts per million) in
    2013

19
GREEN HOUSE GASES AND HUMAN ACTIVITIES
  • II Increase of Methane (CH4) conc.
  • - GWP-25
  • -wet rice cultivation for food
  • -animal husbandry (ruminants release CH4)
  • -methane hydrate in glaciers
  • -burning of organic matter
  • -natural gas and oil extraction
  • -landfills and there decomposition
  • III Increase of Nitrous oxide (N2O) conc.
  • - GWP-298
  • -released from cultivation practices
  • -fertilizers
  • -fossil fuel burning
  • -industries

20
GREEN HOUSE GASES AND HUMAN ACTIVITIES
  • IV Release of chlorofluorocarbons (CFCs)
  • - GWP-10,000
  • -refrigerators
  • -volatile cleaning liquids
  • -spray propellants
  • V Stratospheric ozone (O3)
  • -air pollution
  • VI Sulphur hexafluoride (SF6)
  • - GWP-22,800
  • -electric transmission system
  • -magnesium and aluminium processing
  • VII Perfluorocarbon (PCFs)
  • - GWP-12,200
  • -semiconductor manufacturing

21
SOME COMMON EFFECTS
  • GLOBAL CHANGES
  • -Temperature increase
  • -Droughts
  • -Intensity of Hurricanes increases
  • -Heavy rain events
  • -Rising of sea level
  • -Melting of glaciers
  • Nearly 1000mm rain fall on Mumbai in 18 hours,
    July, 26.2005, made flooded conditions
  • Spain and Portugal experienced their worst
    drought in 60 years, wheat harvest went down by
    50
  • In 2003, European summer was very hot , killed
    30,000 peoples
  • Central America and Canada were usually wet ,
    experienced floods

22
SOME COMMON EFFECTS contd..
  • Warmer oceans will damage corals that are home to
    a million different kinds of plants and animals,
    effect marine life
  • Erosion and loss of top soil, desertification
  • Rise of levels of salt into coastal marshes and
    aquifers
  • Drying of fresh water, Himalayan Glaciers
  • In 2007, water scarcity in Australia, irrigation
    was cut off
  • 2500 sq. Km of China becomes desert each year
  • Glaciers and lakes feeding the yellow river in
    China are shrinking
  • Worlds third largest ice field has melted in
    Nepal, threat of flood to densely populated
    valleys
  • Extinction of stressed plant and animal species

23
SOME COMMON EFFECTS contd..
  • Spread of Waterborne Diseases
  • Malaria
  • Dengue Fever
  • Cholera
  • Typhoid fever
  • Evidence the Caribbean region has experienced a
    marked increase in the incidence of dengue and
    dengue hemorrhagic fever in the past decade
    (Caribbean Epidemiology Centre -CAREC).
  • The region is southeast of the Gulf of Mexico and
    the North American mainland, east of Central
    America, and north of South America.

24
REFERENCES
  1. Rajagopalan, R.2009. Environment And Ecology
    Oxford University Press, New York
  2. Hadson, Travis.2011, Living With Earth, An
    Introduction To Environmental Geology Pearson
    Education, U.S.A.
  3. Wright, T. Richard and Boore, F. Dorothy. 2011,
    Environmental Science, Toward A Sustainable
    Future Pearson US
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