EGU General Assembly 2020
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Cooling and freshening of the eastern equatorial Pacific over the last 2000 years

Gerald Rustic1,2, Athanasios Koutavas2,3, and Thomas Marchitto4
Gerald Rustic et al.
  • 1Rowan University, School of Earth and Environment, Department of Geology, Glassboro, United States of America (
  • 2Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States
  • 3College of Staten Island, City University of New York, NY, United States
  • 4University of Colorado, Department of Geological Sciences, Boulder, CO, United States

Sea surface temperatures in the eastern equatorial Pacific exert powerful influence on the climate beyond the tropics through strong atmosphere-ocean coupling. Records of eastern Pacific sea surface temperatures are of vital importance for identifying the linkages between short-term climate variability and long-term climate trends. Here we reconstruct eastern equatorial Pacific sea surface temperature and salinity from paired trace metal and stable isotope analyses in foraminifera from a sediment core near the Galápagos Islands. Sea surface temperatures are correlated with reconstructed Northern and Southern hemisphere temperature records suggesting a common origin. We propose that this temperature signal originates in the extra-tropics and is transmitted to the eastern Pacific surface via its source waters. We find exceptions to this cooling during the Little Ice Age and during the last century, where notable sea surface temperature increases are observed. We calculate δ18Osw from paired stable isotope and trace element analyses and derive salinity, which reveals a significant trend toward fresher surface waters in the eastern equatorial Pacific. The overall trend toward cooler and fresher sea surface conditions is consistent with longer-term trends from both the Eastern and Western Pacific.

How to cite: Rustic, G., Koutavas, A., and Marchitto, T.: Cooling and freshening of the eastern equatorial Pacific over the last 2000 years , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12476,, 2020


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