Last Glacial Maximum (LGM)

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Last Glacial Maximum (LGM)

• Reading is Chapter 12 in Ruddiman 2nd ed

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Boundary Conditions

• Removed figure for copy right reasons.
• Figure 12-1 from Earth's Climate - Past and
  Present by William Ruddiman 2008

3
Boundary Conditions

• Removed figures for copy right reasons.
• Figure 12-1 from Earth's Climate - Past and
  Present by William Ruddiman 2008
• Figure 7-2 from Earth's Climate - Past and
  Present by William Ruddiman 2008

Obliquity From Analyseries
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CLImate MApping and Prediction

• The project was funded by the NSF
• Imbrie, Hays, and Shackleton
• Reconstruct LGM
• Sediment cores to reconstruct oceanic conditions
• Vegetative zones
• Extent of glaciation

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In class activity part 1

• In groups of four
• Skim the CLIMAP papers for the assumptions
  (modern and/or LGM) used in the model-based LGM
  reconstruction
• CLIMAP (1976), The surface of the ice-age earth,
  Science, 191(4232), 1131-1137.
• CLIMAP (1984), The last interglacial ocean,
  Quatern. Res., 21(2), 123.
• Compare between papers

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CLIMAP assumptions
Assumptions Modern LGM
Sea level
Land albedo
Ice sheets
Ice margins
Ocean temp
Sea Ice
Insolation
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In class activity part 2

• Lets look at the model results from CLIMAP for
  the LGM
• in your web browser, go to
• http//iridl.ldeo.columbia.edu/SOURCES/.CLIMAP/

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Modern vs. LGM
Data Set
aug SST
feb SST
elevation
glacial_ice
relief type
exposed_soil
soil type
vegetation type
vegetative
water
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Temperature in the Tropics
Average of the Tropics Modern LGM
Aug
Feb