Western Pacific Warm Pool Pleistocene paired d18O-Mg/Ca and SST Reconstruction de Garidel-Thoron, T.; Rosenthal, Y.; Bassinot, F.C.; Beaufort, L. de Garidel-Thoron, T. Rosenthal, Y. Bassinot, F.C. Beaufort, L. Sea Surface Temperature Reconstruction earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,composited,null,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Globigerinoides ruber pink,null,per mil PDB,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (magnesium/calcium,Globigerinoides ruber,null,dimensionless,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (age,null,null,radiocarbon year before present,null,paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (sea surface temperature,magnesium/calcium,null,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,"Globigerinoides ruber, white, 250-300mm") earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (MD97-2140>LATITUDE 2.03>LONGITUDE 141.77) About 850,000 years ago, the period of the glacial cycles changedfrom 41,000 to 100,000 years. This mid-Pleistocene climate transition has been attributed to global cooling, possibly causedby a decrease in atmospheric carbon dioxide concentrations. However, evidence for such cooling is currently restricted to thecool upwelling regions in the eastern equatorial oceans, although the tropical warm pools on the western side of the ocean basins are particularly sensitive to changes in radiativeforcing. Here we present high-resolution records of sea surface temperatures spanning the past 1.75 million years, obtained from oxygen isotopes and Mg/Ca ratios in planktonic foraminifera from the western Pacific warm pool. In contrast with the eastern equatorial regions, sea surface temperatures in the westernPacific warm pool are relatively stable throughout the Pleistocene epoch, implying little long-term change in the tropical net radiation budget. Our results challenge the hypothesis of a gradual decrease in atmospheric carbon dioxide concentrationsas a dominant trigger of the longer glacial cycles since 850,000 years ago. Instead, we infer that the temperature contrast across the equatorial Pacific Ocean increased, which might have had a significant influence on the mid-Pleistocene climate transition. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : de Garidel-Thoron, T. Investigator : Rosenthal, Y. Investigator : Bassinot, F.C. Investigator : Beaufort, L. 2005-07-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/2619 https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/md972140-tab.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/degaridel-thoron2005 https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/md972140-tab.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/degaridel-thoron2005 English https://www.ncdc.noaa.gov/paleo/study/2619 https://www1.ncdc.noaa.gov/pub/data/paleo/paleocean/sediment_files/complete/md972140-tab.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/degaridel-thoron2005 de Garidel-Thoron, T., Y. Rosenthal, F.C. Bassinot, and L. Beaufort. 2005. Stable sea surface temperatures in the western Pacific warm pool over the past 1.75 million years. Nature 433, No.7023, 294-298. START YEAR: 1755 14C yr BP * END YEAR: 6 14C yr BP 141.77 2.03 141.77 2.03