Ice Core Records Vostok

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Ice Core Records- Vostok
Petit et al., 1999
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Terminations
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Sequence of Events during Termination
Insolation Increase at high latitudes
Temperature, CO2, CH4 increase and Dust
decreases Ice Volume decreases No one
factor (insolation, greenhouse gases, albedo) can
account for the temperature change. They must
act together as amplifiers.
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Higher Resolution Record
Temperature rise in Antarctica precedes global
CO2 rise Does Southern Ocean control CO2?
Monnin EPICA Dome C (Science 2001)
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Timing during Termination I
How important is dust?
Röthlisberger et al., GRL, 2004
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EPICA Antarctic Ice Core
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Reduced Temperature Cycles
Interglacials were less warm at gt 400K yrs
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Weak interglacials have lower CO2
Siegenthaler et al., Science 2005 (EPICA gas
consortium)
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Weak interglacials have lower CH4
Spahni et al., Science 2005, EPICA gas consortium
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Mudelsee (based only on Vostok data) pCO2 922
1.646 dDt-2000
Does ability to predict global CO2 from Antarctic
temperatures indicate dominance of S. Ocean
mechanisms controlling CO2?
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Termination V (450K yrs BP)
CO2 increase precedes temperature and CH4
increase and dust decrease
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Where do we stand?
Looks like Temperature and Dust changes
precede CO2 and CH4 changes (except Term V).
Increasing evidence that Southern Ocean may be an
important factor in controlling CO2. Is it a
combination of ocean circulation changes and iron
fertilization in the S. Ocean? What is the
implication for future climate change?