Global Warming (Climate Change)

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Global Warming (Climate Change)

• The Greenhouse Effect
• Sunlight streams through the atmosphere and
  heats the Earth. Some of the heat radiates back
  out into space. The rest of the heat is absorbed
  by gases in the troposphere and warms the air.
  The process of heat absorption is called the
  greenhouse effect

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Not every gas in our atmosphere absorbs heat this
way. The gases that do not absorb and radiate
heat are called greenhouse gases. The major
greenhouse gases are water vapor, carbon
dioxide, CFCs , methane and nitrous oxide.
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Major Sources of GHG
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Rising Carbon Dioxide Levels

• In 1958 scientists started
• measuring CO2 levels.
• It quickly became
• apparent that the levels
• where rising.

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Fossil Fuels and Climate Change

• Some scientists believe
• the increase in CO2 may
• be linked to increased
• average atmospheric
• temperatures. Looking at
• ice cores have provided
• some clues to Earths past.

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Average Global Temperatures on the Rise
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Long Term Average Temperatures
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Consequences of a Warmer Earth
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Consequences of a Warmer Earth

• Melting Ice and Rising Sea Levels
• Coastal areas would be flooded
• Coastal aquifers could become too salty
• Change in Global Weather Patterns
• Severe storms could occur more frequently
• and be much stronger
• Floods could occur in one region while drought
  devastates other regions

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Consequences of a Warmer Earth

• Risks to Humans
• Heat could put the very young and very old
• at risk to excessive heat.
• May increase ground level ozone
• Warmer temperature could allow insectbourne
  diseases to spread

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Consequences of a Warmer Earth

• Agriculture
• Droughts and floods would decrease food
• production
• Higher temperatures would put pressure on
• water resources

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What May Help?

• Kyoto Protocol- In 1997
• 160 countries met in
• Kyoto, Japan to try and
• reduce CO2 emissions.
• 55 if attending nations
• signed the treaty to lower
• emissions by 2012.
• U.S. did not sign the treaty