noaa-forcing-24270 Paleo-pCO2 Database Tanzania Early Cenozoic Boron Isotope and CO2 Data Anagnostou, E.; John, E.H.; Edgar, K.M.; Foster, G.L.; Ridgwell, A.; Inglis, G.N.; Pancost, R.D.; Lunt, D.J.; Pearson, P.N. Paleo-pCO2 Database Tanzania Early Cenozoic Boron Isotope and CO2 Data 2018-05-25 NCDC-Paleoclimatology ONLINE Files Pending https://www.ncdc.noaa.gov/paleo/study/24270 Investigator E. Anagnostou Investigator E.H. John Investigator K.M. Edgar Investigator G.L. Foster Investigator A. Ridgwell Investigator G.N. Inglis Investigator R.D. Pancost Investigator D.J. Lunt Investigator P.N. Pearson earth science paleoclimate paleoceanography delta 11B,planktic foraminifer,two standard deviations,per mil,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,column chemistry earth science paleoclimate climate reconstructions|paleoceanography pH,delta 11B,null,dimensionless,null,climate reconstructions|paleoceanography,null,null,N,null earth science paleoclimate climate forcing|paleoceanography carbon dioxide,bulk atmosphere,null,parts per million,null,climate forcing|paleoceanography,null,null,N,based on 11B of planktic foram earth science paleoclimate climate reconstructions|paleoceanography sea surface temperature,magnesium/calcium,null,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,null earth science paleoclimate climate forcing|climate reconstructions|paleoceanography age,null,null,million years ago,null,climate forcing|climate reconstructions|paleoceanography,null,null,N,null earth science paleoclimate paleoceanography delta 11B,planktic foraminifer,null,per mil,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,column chemistry earth science paleoclimate paleoceanography magnesium/calcium,planktic foraminifer,null,millimole per mole,null,paleoceanography,null,null,N,null earth science paleoclimate climate forcing|paleoceanography carbon dioxide,bulk atmosphere,two standard deviations upper bound,parts per million,null,climate forcing|paleoceanography,null,null,N,based on 11B of planktic foram earth science paleoclimate climate forcing|paleoceanography carbon dioxide,bulk atmosphere,two standard deviations lower bound,parts per million,null,climate forcing|paleoceanography,null,null,N,based on 11B of planktic foram earth science paleoclimate climate reconstructions|paleoceanography pH,delta 11B,two standard deviations upper bound,dimensionless,null,climate reconstructions|paleoceanography,null,null,N,null earth science paleoclimate climate reconstructions|paleoceanography pH,delta 11B,two standard deviations lower bound,dimensionless,null,climate reconstructions|paleoceanography,null,null,N,null earth science paleoclimate climate forcing carbon dioxide geoscientificInformation 53200000 cal yr BP 36900000 cal yr BP Complete -9.902254 -8.856207 39.460912 39.704584 Continent Africa Eastern Africa Tanzania Tanzania Drilling Project>LATITUDE >LONGITUDE None Please cite original publication, online resource, dataset and publication DOIs (where available), and date accessed when using downloaded data. If there is no publication information, please cite investigator, title, online resource, and date accessed. The appearance of external links associated with a dataset does not constitute endorsement by the Department of Commerce/National Oceanic and Atmospheric Administration of external Web sites or the information, products or services contained therein. For other than authorized activities, the Department of Commerce/NOAA does not exercise any editorial control over the information you may find at these locations. These links are provided consistent with the stated purpose of this Department of Commerce/NOAA Web site. English DOC/NOAA/NESDIS/NCEI National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce https://www.ncdc.noaa.gov/data-access/paleoclimatology-data DATA Center Contact Bruce Bauer bruce.a.bauer@noaa.gov paleo@noaa.gov 303-497-6280 303-497-6513

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Boulder CO 80305-3328 USA online ASCII Eleni Anagnostou, Eleanor H. John, Kirsty M. Edgar, Gavin L. Foster, Andy Ridgwell, Gordon N. Inglis, Richard D. Pancost, Daniel J. Lunt, Paul N. Pearson 2016 Nature 533 380-384 10.1038/nature17423 https://www.nature.com/articles/nature17423

The Early Eocene Climate Optimum (EECO, which occurred about 51 to 53 million years ago), was the warmest interval of the past 65 million years, with mean annual surface air temperature over ten degrees Celsius warmer than during the pre-industrial period. Subsequent global cooling in the middle and late Eocene epoch, especially at high latitudes, eventually led to continental ice sheet development in Antarctica in the early Oligocene epoch (about 33.6 million years ago). However, existing estimates place atmospheric carbon dioxide (CO2) levels during the Eocene at 500-3,000 parts per million, and in the absence of tighter constraints carbon-climate interactions over this interval remain uncertain. Here we use recent analytical and methodological developments to generate a new high-fidelity record of CO2 concentrations using the boron isotope (d11B) composition of well preserved planktonic foraminifera from the Tanzania Drilling Project, revising previous estimates. Although species-level uncertainties make absolute values difficult to constrain, CO2 concentrations during the EECO were around 1,400 parts per million. The relative decline in CO2 concentration through the Eocene is more robustly constrained at about fifty per cent, with a further decline into the Oligocene. Provided the latitudinal dependency of sea surface temperature change for a given climate forcing in the Eocene was similar to that of the late Quaternary period, this CO2 decline was sufficient to drive the well documented high- and low-latitude cooling that occurred through the Eocene. Once the change in global temperature between the pre-industrial period and the Eocene caused by the action of all known slow feedbacks (apart from those associated with the carbon cycle) is removed, both the EECO and the late Eocene exhibit an equilibrium climate sensitivity relative to the preindustrial period of 2.1 to 4.6 degrees Celsius per CO2 doubling (66 per cent confidence), which is similar to the canonical range (1.5 to 4.5 degrees Celsius), indicating that a large fraction of the warmth of the early Eocene greenhouse was driven by increased CO2 concentrations, and that climate sensitivity was relatively constant throughout this period. STUDY NOTES: Paleo-CO2 derived from boron isotope measurements on planktonic foraminifera samples from Tanzania Drilling Project cores TDP3/5-1, TDP2/19-1, TDP2/9-3, PP98L-2, and TDP18/18-2 for the early Cenozoic (53.2 - 36.9 ma), contributed to the Paleo-pCO2 Database.

GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/anagnostou2016boron.xlsx Excel File; Tanzania Early Cenozoic Boron Isotope and CO2 Data GET DATA https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/anagnostou2016boron.txt NOAA Template File; Tanzania Early Cenozoic Boron Isotope and CO2 Data USA/NOAA DIF Version 9.8.4 2018-12-11 2018-12-11