Greenhouse%20Earth

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Greenhouse Earth

• Greenhouse Effect Intro

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Greenhouse Effect

• The earths atmosphere traps sunlight like glass
  on a greenhouse
• The Earth absorbs the heat and releases it to
  warm the air
• The rest of the heat gets trapped by the gases in
  the troposphere
• Some gases radiate heat instead of trapping them
  these are the greenhouse gases

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• Major greenhouse gases
• Water Vapor H2O
• Carbon Dioxide CO2
• Chlorofluorocarbons CFCs
• Methane (natural gas) CH4
• Nitrous oxide NO2
• Ozone (in the troposphere) O3
• Water vapor and CO2 are the most abundant

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How can we tell how much CO2 is in the
atmosphere?

• Carbon dioxide naturally fluctuates
• Photosynthesis, pollutants
• 1958 Charles Keeling measured the CO2 in the
  air at Mauna Loa in Hawaii
• Reasoning the air comes from the Pacific, far
  from forests and cities
• Most accurate representation of the atmosphere

• March 1958 314ppm
• (.0314)
• An increase was seen in only a few years
• 1968 320ppm
• 1978 332ppm
• 1988 348ppm
• 1994 358ppm

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• Greenhouses gases trap heat near the surface
• More greenhouse gases warmer Earth
• We are releasing more CO2 into the atmosphere
  than ever before
• Prediction Earths temperature will increase by
  4º by 2050
• This predicted increase in temperature is known
  as global warming

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• The Earth has had drastic changes in its climate
  in the past
• Ice ages
• These took thousands of years
• No one is sure what the effects of global warming
  will be or how severe
• Computer simulations tell us

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Weather

• If the Earth heats up significantly, oceans will
  warm which will make hurricanes and typhoons more
  common
• If the weather patterns are affected, it could
  change the ocean patterns
• Disruptions in weather would affect agriculture
  farming weather may shift Northward out of the
  Midwest

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Oceans

• Polar ice caps melt and raise sea levels
• Glaciers mass of ice and snow on land
• Iceberg chunk of glaciers that breaks off and
  falls into the water
• Higher sea levels would cause parts of land to be
  covered
• California, Louisiana, parts of Florida
• US is shrinking

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STOP IT!

• Reduce burning fossil fuels
• Plant more trees
• 100 million new trees would reduce 18 million
  tons of carbon in the atmosphere
• Review
• Global Warming Interactive