Can a better understanding of climate-society interactions during the MWP-to-LIA epochs help us plan for future (anthropogenic) climate change effects?

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• What do we know about climate patterns during
  the MWP LIA? How different are they from the
  20th Century?
• What do we know about socioeconomic changes
  during that time?

• Can a better understanding of climate-society
  interactions during the MWP-to-LIA epochs help us
  plan for future (anthropogenic) climate change
  effects?

Welcome and Aloha!
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There is a good deal of overlapping proxy and
model data consistent with a La Niña like
tropical Pacific in Medieval times (both in the
tropics and the mid-latitudes). As simulated by
models or inferred from proxy records, changes in
tropical SST would drive very large climate
changes in the Pacific basin. What would
happen to ecosystems and cultures in this region
if this pattern were to reoccur?
One goal is to examine the pros and cons for
cool tropical Pacific during MWP. Some of the
cultural/ecologic changes associated with late
Medieval (MWP-LIA transition) are described
collectively in Patrick Nunn's papers.
Welcome and Aloha!
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PACIFIC MARINE PROXY RECORDS
Source Graham et al. Clim. Change (2007)
CORRELATIONS SST WITH NINO3 SST
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Two reference sources on these events yield very
similar results about 35 precip deficit for
50-100 years
MONO LAKE MODERN NATURAL LEVEL
14C dates
LOW STANDS FROM STINE (1994)
LOW STANDS FROM STINE (1994)
Graham and Hughes (In press).
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Source Graham et al. (2007), Climatic Change
lt -1.5C
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PDSI MCA - POST-MCA DIFFERENCES
COVARIANCE PC 1 vs PALMYRA CORAL d18O
PDSI Cook et al. (2004) Palmyra Cobb et al.
(2003)
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CCM3 MCA SIMULATION GCM FORCED WITH
INFERRED MCA TROPICAL PACIFIC SST PATTERN BASED
ON THE PALMYRA MINDANAO PROXY RECORDS 40
ENSEMBLE MEMBERS IDEALIZED ENSO VARIABILITY
DEC. - MARCH
MARCH - JUNE
Simulations by T. Xi and M. Hoerling, NOAA
CDC c.f. Herweijer, Seager, and Cook, 2005
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Session 1 Paleoenvironmental studies archives,
proxy records, pre-history, and early history of
Pacific Island societies A Shock to the system
Climatic disruption of Pacific Island societies
around AD 1300 Patrick Nunn Environmental
change and cultural response in the Pacific
Islands over the last millennium Simon Haberle