Pliocene Northern Hemisphere Glaciation Marine Proxy Data
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               World Data Center for Paleoclimatology, Boulder
                                  and
                     NOAA Paleoclimatology Program
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NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!!


NAME OF DATA SET: Pliocene Northern Hemisphere Glaciation Marine Proxy Data
LAST UPDATE: 2/2007 (Original receipt by WDC Paleo)
CONTRIBUTORS: Manfred Mudelsee and Maureen E. Raymo 
IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2007-022

SUGGESTED DATA CITATION: Mudelsee, M., and M.E. Raymo.  2007. 
Pliocene Northern Hemisphere Glaciation Marine Proxy Data.
IGBP PAGES/World Data Center for Paleoclimatology 
Data Contribution Series # 2007-022.
NOAA/NCDC Paleoclimatology Program, Boulder CO, USA.


ORIGINAL REFERENCE: Mudelsee, M., and M.E. Raymo. 2005.
Slow dynamics of the Northern Hemisphere glaciation.
Paleoceanography, Vol. 20, PA4022, doi:10.1029/2005PA001153
December 2005.


ABSTRACT:
Unraveling the dynamics of the Northern Hemisphere glaciation (NHG) 
in the Pliocene is a key step toward a quantitative theory of the 
climate transition from a greenhouse to an icehouse world. 
Extracting the ice volume signal from marine oxygen isotope (d18O) 
records corrupted with "temperature noise" can be accomplished using 
statistical time series analysis. We use 45 d18O records from benthic 
and planktonic foraminifera and globally distributed sites to reconstruct 
the dynamics of NHG initiation.  We compare d18O amplitudes with those 
of temperature proxy records and estimate a global ice volume–related 
increase of 0.4%, equivalent to an overall sea level lowering of 43 m.  
We find the NHG started significantly earlier than previously assumed, 
as early as 3.6 Ma, and ended at 2.4 Ma. This long-term increase points 
to slow, tectonic forcing such as closing of ocean gateways or mountain 
building as the root cause of the NHG.

GEOGRAPHIC REGION: Global
PERIOD OF RECORD: Pliocene, ~3.6 Ma. - 2.4 Ma.

FUNDING SOURCE: Deutsche Forschungsgemeinschaft (DFG),
Bonn, Germany (MU 1595/2 to M.M.)

DESCRIPTION:
The database consists of 45 marine proxy records for ice volume and temperature 
(d18O, Mg/Ca, faunal assemblages). A new, absolutely dated magnetobiostratigraphic
timescale was developed to redate older time series (published before 1994) and 
erect an accurate time frame for the 2–4 Myr interval. The magnetostratigraphic
dates exhibit an excellent agreement with astronomically tuned dates, with the 
average error ~25,000 years.

Individual data files contain previously published series and original references.
Data currently posted here are series previously archived with NOAA/WDC Paleo.
Additional series will be posted in this directory after permission is obtained 
from the original authors.