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Mid-piacenzian of the north Atlantic Ocean

Harry J. Dowsett·Marci M. Robinson·Kevin M. Foley·Timothy D. Herbert·Bette L. Otto-Bliesner·Whittney Spivey
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Abstract

The Piacenzian Age (Pliocene) represents a past climate interval within which frequency and magnitude of environmental changes during a period of past global warmth can be analyzed, climate models can be tested, and results can be placed in a context to better prepare for future change. Here we focus on the North Atlantic region, incorporating new and existing faunal assemblage and alkenone data from Ocean Drilling Program Sites 642, 662, 982, and 999, and International Ocean Discovery Program Sites 1308 and 1313 into our paleoenvironmental reconstruction. Cores and outcrop material containing Piacenzian sediments from the Atlantic Coastal Plain of Virginia, USA, are also included. These data allow us to characterize regional changes in temperature, salinity, upwelling, surface productivity, and diversity, associated with climate transitions, and make nuanced reconstructions of mid-Piacenzian conditions within a high-resolution temporal framework between ~3.40 and ~3.15 Ma, inclusive of Marine Isotope Stages M2 through KM5. We include an initial comparison of estimated sea-surface temperature to coupled climate model simulations, which shows improvement in model adherence to paleoclimate parameters over previous data-model comparisons for the Pliocene.

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Harry J. Dowsett, Marci M. Robinson, Kevin M. Foley, Timothy D. Herbert, Bette L. Otto-Bliesner, Whittney Spivey. 2018-08-12. Mid-piacenzian of the north Atlantic Ocean. https://doi.org/10.29041/strat.16.3.119-144

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