ENVIRONMENTAL SCIENCE

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ENVIRONMENTAL SCIENCE

• ENVS 1401

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Science

• Astronomy
• Physics
• Chemistry
• Geology
• Biology
• Cell biology
• Microbiology
• Anatomy
• Physiology
• Ecology

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Science

• What do the Sciences have in common?
• Why are they science?
• Use Scientific Method.
• Rational, organized procedure for discovery,
  understanding of nature.
• Empirical based on experience
• Factual information data
• Repeatable

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Scientific Method
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EXPERIMENT

• Controlled process for testing a hypothesis
• Experimental variable subject of hypothesis
• Controlled variables ALL other effects that
  could influence outcome
• Held constant across all treatments

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EXPERIMENT

• Example Redi's experiment
• Dogma Maggots are spontaneously generated from
  spoiled meat.
• Redis hypothesis Maggots come from flies (not
  spontaneous generation)

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A hypothesis may be verified, but never proven!
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Proof (Geometry)
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Biological hypothesis

• Homunculus hypothesis
• Reproduction by fully formed embryo
• in father ??
• in mother ??
• Discovery of sperm ovum verification !
• living cells could contain homunculi

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Biological hypothesis

• Homunculus hypothesis
• Sperm ovum later shown NOT to contain homunculi
• Chromosomes, DNA instead
• Hypothesis FALSIFIED !

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Theory Law

• Theory (only a theory ??)
• Well-tested, verified hypothesis
• General applicability
• Shown highly reliable in predicting future
  results
• But, never proven.
• Law
• Old and well-accepted theory
• Law of Gravity, Laws of Thermodynamics
• Still, never proven !

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LIMITS of SCIENCE

• Science studies phenomena that are
• observable,
• objectively
• quantifiable,
• measurable
• repeatable.

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LIMITS of SCIENCE

• Science can NOT address questions of Religion,
  Philosophy, Arts.
• Religion.
• Is there a god? What is nature of God?
• Philosophy.
• What is justice? Is capital punishment "cruel
  and unusual?"
• Arts.
• Is jazz good music?
• Should DaVinci have painted a background in the
  Mona Lisa?

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Frontier Consensus Science

• Frontier science
• Investigations in new and controversial areas
• Results meaning uncertain
• Genetic engineering of crop plants
• Estrogen-like properties of PCBs
• Consensus science
• Well-established theory, widely accepted
• Germ theory of disease
• Plant nutrition with fertilizers

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Difficulty of Environmental Science

• Complexity of systems (esp. on global scale)
• Difficulty of controlled experiments
• Difficulty interpreting and understanding results

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Difficulties of Environmental Science.

• How would we design experiments to test these
  hypotheses??
• Manipulative science
• Impractical to experiment on global scale
• Long time to obtain results
• Natural experiment
• Compare place to place, or time to time

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Difficulties of Environmental Science.

• Example
• Addition of CO2 to atmosphere from burning fossil
  fuels (coal, petroleum)
• CO2 absorbs heat ? warming of atmosphere,
• CO2 promotes plant growth (removes CO2 from air),
• CO2 absorbed in oceans, promotes growth of
  corals, etc.,
• Warming atmosphere allows growth of crops farther
  north,
• Warming atmosphere produces more more violent
  storms,
• Warming atmosphere may melt glaciers, permafrost,
  raise sea levels, destroy coastal cities,
• more ??