Upwelling Intensification As Part of the Pliocene-Pleistocene Climate Transition
Jeremy R. Marlow,1*
Carina B. Lange,2
Gerold Wefer,3
Antoni Rosell-Melé4
A deep-sea sediment core underlying the Benguela
upwelling system off southwest Africa provides a continuous time series
of sea surface temperature (SST) for the past 4.5 million years. Our results indicate that temperatures in the region have declined by
about 10°C since 3.2 million years ago. Records of paleoproductivity suggest that this cooling was associated with an increase in
wind-driven upwelling tied to a shift from relatively stable global
warmth during the mid-Pliocene to the high-amplitude
glacial-interglacial cycles of the late Quaternary. These observations
imply that Atlantic Ocean surface water circulation was radically
different during the mid-Pliocene.
1 Department of Fossil Fuels and Environmental
Geochemistry, Drummond Building, University of Newcastle, Newcastle
upon Tyne, NE1 7RU, UK.
2 Geosciences Research
Division, Scripps Institution of Oceanography, University of California
at San Diego, La Jolla, CA 92093, USA.
3 Department
of Earth Sciences (FB-5), University of Bremen, Postfach 330440, 28334 Bremen, Germany.
4 Department of Geography,
University of Durham, Durham, DH1 3LE,UK.
*
To whom correspondence should be addressed. E-mail:
J.R.Marlow{at}ncl.ac.uk
