Kuroshio Extension Oxygen Isotope Data During the Pliocene-Pleistocene Climate Transition Venti, N.L.; Billups, K. Venti, N.L. Billups, K. earth science/paleoclimate/paleoceanography (depth,null,null,meter,null,paleoceanography,null,null,N,core top depth) earth science/paleoclimate/paleoceanography (age,null,null,calendar kiloyear before present,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth,null,null,meter,null,paleoceanography,null,null,N,"mbsf; unique(""recompressed"")") earth science/paleoclimate/paleoceanography (depth,null,null,meter,null,paleoceanography,null,null,N,shipboard reported depth) earth science/paleoclimate/paleoceanography (notes,null,null,null,null,paleoceanography,null,null,N,core recovery percent) earth science/paleoclimate/paleoceanography (delta 18O,Globigerinoides ruber,null,per mil PDB,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean (ODP 1208>LATITUDE 36.127>LONGITUDE 158.2016) The Pliocene–Pleistocene climate transition offers an opportunity to study the effect of glaciation on the ocean–climate system. We present a Globigerinoides ruber δ18O record from Ocean Drilling Program Site 1208 (Kuroshio Current Extension; KCE). This exclusively (sub)tropical foraminifer, a summer/fall mixed-layer dweller at the KCE, affords the first long (3.0 Ma to 1.8 Ma) orbital-scale (2.5-kyr time step) account of the sea surface in this area. The section's temperature-corrected benthic foraminiferal δ18O record constrains global changes in ice volume, yielding a Δδ18O record that primarily reflects summer/fall KCE hydrography (temperature and salinity). A 0.3‰ decrease in Δδ18O values at 2.7 Ma coincides with the onset of Northern Hemisphere glaciation, indicating as much as 1.5°C warming during the summer/fall to suggest that the subtropical North Pacific sea surface provided heat and moisture for expanding ice sheets. On the orbital scale, the 41-kyr cycle that dominates high-latitude climate is absent from the Δδ18O record, indicating a stable surface water hydrographic regime on this time scale. Rather, the Δδ18O record varies at and is coherent with the 19-kyr precessional component of the regional insolation curve, supporting a direct response to subtropical insolation and insensitivity to extra-regional forcing factors, such as ice sheets. STUDY NOTES: Oxygen isotope measurements of Globigerinoides ruber span the Plio-Pleistocene boundary (3.0 to 1.76 Ma) at 2500-year time step. Stable-isotope analyses were conducted at the University of Delaware with the GV Instruments IsoPrime dual-inlet mass spectrometer. Oxygen isotopic values have been corrected to the Peedee Belemnite standard using NBS-19 and Carrara Marble as an in-house standard. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Venti, N.L. Investigator : Billups, K. 2013-04-02 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/14170 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/venti2013/venti2013.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/venti2013/venti2013.txt English https://www.ncdc.noaa.gov/paleo/study/14170 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/venti2013/venti2013.txt Venti, N.L., and Billups, K.2013Surface water hydrography of the Kuroshio Extension during the Pliocene-Pleistocene climate transitionMarine Micropaleontology101106-11410.1016/j.micro2013.02.004 START YEAR: 3000000 cal yr BP * END YEAR: 1760000 cal yr BP 158.2016 36.127 158.2016 36.127