2. The Changing Global Environment

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2. The Changing Global Environment

• Geological Base Climate Climate Change Water
  Human Impacts on Plants Animals Food Resources

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Figure 2.2, Plate Tectonics
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Figure 2.3, Global Tectonic Plates
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Geology Human Settlement A Restless Earth

• Plate Tectonics/Continental Drift
• Break-up of Africa centered supercontinent
  Pangaea c. 250 million yrs Before Present (BP)
• Formation of Tethys Sea
• Removal of Australia from main evolutionary line
  in Pangaea and around Tethys Sea
• Removal and return of India to create Himalayan
  Mountain Range
• Formation of major fold mountain ranges along
  leading edges of North and South American Plates
• At human scale, problems of earthquakes and
  volcanic activity along plate boundaries
• Plate Tectonic Theory confirms Evolutionary
  Theory
• Collapse of Reptiles as dominant species c. 65
  million years BP, probably because of impact of
  asteroid in Yucatan peninsula

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Figure 2.3, Global Tectonic Plates
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Figure 2.7, Global Earthquakes and Volcanoes
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Climate Change

• Climate change natural, anthropogenic, or both?
• Glacial, interglacial, interstadial climates
• Natural change--a historic pattern of 400 to 600
  years interval for the past 2,000 years?
• Evidence for change (the church wine production
  in Europe).
• Shift in North Atlantic Drift
• Rice cultivation in China
• Deforestation in Europe
• Recent anthropogenic change
• Burning hydrocarbons produces carbon dioxide.
  CO2 main contributor to Global Warming (Table
  2.1)
• Large scale CO2 production began late 1770s
  w/Industrial Revolution coal burning
• Modern CO2 production largely from automobile
  fleet
• Only EU has attempted to mitigate automobile CO2
  output

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Figure 2.11 Global Pressure Systems
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Climate

• Planetary heat transfer from Equatorial to Polar
  regions
• Planet takes in more solar radiation between
  Tropics of Cancer and Capricorn than it loses,
  loses more from Polar regions than is coming in
  (see Fig. 2.1)
• Hot air and water masses move polewards, cold air
  and water returns toward Equator
• Planetary heat transfer us
• Warms west coasts of continental masses
• W. Europe main beneficiary
• Provided main power source (wind) for planetary
  movement (ships) from late 1400s to mid-1800s

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Table 2.1 (3rd edn) the Worlds Major CO2
Polluters
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Table 2.1 (4th edn) the Worlds Major CO2
Polluters
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Water on Earth A Scarce Polluted Resource

• Only 3 of worlds water is fresh water, most of
  it is ice, there is rarely enough where humans
  want it!
• Except when it floods. Floods cause more
  fatalities than any other natural disaster. Too
  many people live in flood prone regions (e.g.
  Bangladesh)
• Much water is polluted runoff has been
  increased by deforestation
• Water more valuable than oil
• Most destructive use of water is in agriculture
  (evaporation)
• Use in closed systems (water for sewage disposal,
  washing etc.) allows recycling (tho at some cost)
• When there is water policy it tends to underprice
  water
• Texas had no comprehensive water plan until
  Senate Bill 2 took effect 9/1/2001

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Human Impacts on Plants Animals

• For most of human history we collected and hunted
  food
• C. 20,000 BP Agricultural Revolution (AR)
  improved food supply, but still erratic. Protein,
  inputs dropped. AR encouraged human crowding (bad
  for health-poor waste disposal etc.) Food surplus
  made urban life civilization possible, allowed
  division of labor, elites
• Population rose rapidly, then leveled off
• AR Plants chosen for productivity, ease of
  cultivation
• Animal resources added later to do work, for
  protein, for fiber
• Organic Society marked by 3Fs. Food, Fiber, Fuel
  all grown in Organic Society
• Land resources allocated between 3Fs according to
  population pressure, environmental needs etc.
• Humans lived on, at best, c. 3 million cals. each
  per year

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Figure 2.19 World Bioregions
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Food resources environment, diversity,
globalization

• Industrial Revolution c. 200 years BP transformed
  human societies and economies
• Better transport made food supply much more
  reliable
• Better public health began inexorable increase in
  human life expectancy
• Fossil fuel inputs took fuel out of 3F equation,
  then fiber, thus more land for food
• Population skyrocketed, in part because of more
  reliable food supply (remember that deaths drop
  before births in classical version of Demographic
  Transition-DR)
• Global population currently showing signs of
  reduced rates of increase (i.e. reaching stage 3
  of DR)
• Fossil fuel inputs to food now immense in
  developed world (10 calories in, 1 cal vegetable
  energy out 10 cals vegetable energy in, 1 cal
  beef protein out)
• Calorie consumption per head in America now c.
  100 million calories per year
• Rest of developed world much lower (Germany c.
  40, Japan below 30)
• LDCs starting to catch up very quickly in
  consumption (remember increase in Chinas CO2
  output)

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World Population Grain Production
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Grain for people vs grain for biofuels

• World grain supply only just keeping pace w/world
  population growth
• North America and EU are worlds only large scale
  exporters of grain
• Grain in NA, EU requires high fossil energy
  inputs
• Public policy in US has reduced world grain
  supply by diverting corn to biofuel production,
  casuing sharp rises in grain prices
• Biofuels from food grains actually have negative
  impact (more calories in than calories out) as
  well as other negatives (increase in greenhouse
  gasses)

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The next 50 years in energy (this is your life
part 1)

• Serious and accelerating climate change (now
  looks fundamentally irreversible, although better
  public policy could reduce impact)
• Short term energy crisis (likely to see 30
  years of steadily rising prices and accelerating
  demands for efficiencies in usage of fossil fuels
  and electricity, most of which still comes from
  fossil fuels)
• Some solutions unlikely if examined closely-clean
  coal for example. World has coal in abundance but
  generating electricity with coal results in much
  higher CO2 output per unit energy generated than
  using natural gas. China, India, building huge
  new coal plants
• Long term energy stability, assuming renewed
  investments in nuclear power, substantial
  investment in wind power, ramped up research into
  alternate fuels
• Main shortfalls will be in liquid hydrocarbons
  for air transport and as raw materials for
  plastics

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The next 50 years in the environment (this is
your life part 2)

• Global warming, global warming, global warming
• Plausible rise in hurricane/cyclone frequency
• Massive rise in flood related deaths in LDCs
• Serious threats to coastal cities around world
• What is currently happening to New Orleans will
  become commonplace
• Capital coast of defending coastal cities will
  necessitate huge increases in public spending or
  abandonment of such cities
• Potable water will become substantially more
  expensive, not least as salt water from rising
  sea levels penetrates coastal aquifers

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Books worth reading

• Kenneth S. Deffeyes, 2005. Beyond Oil the View
  from Hubberts Peak. NY Hill Wang
• Bruce Podobnik, 2006. Global Energy Shifts
  Fostering Sustainability in a Turbulent Age.
  Philadelphia Temple University Press
• Spencer W. Weart, 2003. The Discovery of Global
  Warming. Cambridge Harvard University Press