COLLABORATIVE RESEARCH: HIGH RESOLUTION PALEOCEANOGRAPHY IN THE HEART OF THE EQUATORIAL PACIFIC COLD TONGUE

The Eastern Equatorial Pacific (EEP) plays a key role in global climate and ocean biogeochemistry. Using a recently collected series of cores from the Peruvian margin, this collaborative research generates an integrated paleoceanographic data set from this region, including alkenones, trace elements, stable isotopes, and sediment composition. These data are used to document lateral and vertical gradients in key aspects of physical, biological, and geochemical properties of the cold tongue region of the EEP. The approach is structured around three time streams of increasingly high resolution: last glacial maximum (LGM) through Termination I, the Holocene, and the last 2 millennia. The research team tests the hypothesis that the paleoceanography of the EEP has been dictated by two distinct drivers: the remote influence of the high latitude southern ocean, which dominated surface and subsurface properties from the LGM to the middle Holocene, and tropical dynamics which drove the modern El Nino-Southern Oscillation (ENSO) system over the past ~5 ky. Broader impacts include graduate and post-doctoral training, internships for disadvantaged high school students, and collaborations with South American scientists.