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USGS · 70029327

Middle Pliocene sea surface temperature variability

H.J. Dowsett·M.A. Chandler·T. M. Cronin·Gary S. Dwyer
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Abstract

Estimates of sea surface temperature (SST) based upon foraminifer, diatom, and ostracod assemblages from ocean cores reveal a warm phase of the Pliocene between about 3.3 and 3.0 Ma. Pollen records and plant megafossils, although not as well dated, show evidence for a warmer climate at about the same time. Increased greenhouse forcing and altered ocean heat transport are the leading candidates for the underlying cause of Pliocene global warmth. Despite being a period of global warmth, this interval encompasses considerable variability. Two new SST reconstructions are presented that are designed to provide a climatological error bar for warm peak phases of the Pliocene and to document the spatial distribution and magnitude of SST variability within the mid-Pliocene warm period. These data suggest long-term stability of low-latitude SST and document greater variability in regions of maximum warming. Copyright 2005 by the American Geophysical Union.

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H.J. Dowsett, M.A. Chandler, T. M. Cronin, Gary S. Dwyer. 2005-06-10. Middle Pliocene sea surface temperature variability. https://doi.org/10.1029/2005pa001133

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