PresentDay Glaciers Points to Consider

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Present-Day GlaciersPoints to Consider

• Land Area Covered
• As a Source of Water
• As Hazards to Mankind
• Icebergs
• Surging Glaciers
• Outburst Floods
• Contributors to Landslides and Mudflows

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Present-Day GlaciersLand Area Coveredcurrently
about 10
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Present-Day GlaciersAs a Source of Water

• Just over 2 of worlds water supply.
• 75 of worlds fresh-water supply.
• Most is inaccessible (Antarctica, Greenland)
• Important water source (together with snow melt)
  in areas near mountains.
• Melting ? rise in sea level ( 200 feet if all
  of it melted).

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Present-Day GlaciersAs Hazards to Mankind
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Past GlaciationsPoints to Consider

• Land Area Covered During Great Ice Age
• Multiple Glaciations
• Legacies of the Great Ice Age
• Landscape Effects
• Natural Resources
• Effects on Organisms

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Past GlaciationsLand Area Covered

• 30 of worlds land area
• Principally in Northern Hemisphere
• Major Ice Sheets
• Mountain Ice Caps

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Past GlaciationsMultiple Glaciations

• Perhaps 35 in last 2.0 to 2.5 Myr.
• Not always the same areas covered.
• Each glaciation followed by an
  interglaciation.

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Past GlaciationsLegacies

• Landscape Effects
• Direct areas of glacial erosion and deposition.
• Indirect examples - effects of
• Related changes in climate.
• Pluvial lakes
• Changes in volume of ocean water sea level
  response.
• Post-glacial changes - Great Lakes.

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Past GlaciationsLegacies

• Natural Resources
• Water Resources - lakes, ground water.
• Mineral Resources - sand and gravel, clay, peat

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Past GlaciationsLegaciesEffects on Organisms

• Shifts of vegetation belts, associated animal
  life.
• Migration of animals, including man.

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Future GlaciationsPoints to Consider

• Link of Glaciers and Climate
• Prediction of the Next Glaciation

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Future GlaciationLink of Glaciers and Climate

• What climatic factors cause and maintain a
  glaciation, then end it?
• What causes changes in our climate?

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Future GlaciationsPrediction

• Of the next glaciation. How long to develop
  full-glacial conditions?
• Of the next cold (periglacial) climate?
• Only a century?
• Methodology
• Study all evidence of climatic change
• Includes behavior of glaciers themselves.
• Is a change local, or regional, even global?
• Mans effects on climate?