Paleo-pCO2 Database Atlantic 30,000 Year Boron Isotope and CO2 Data Henehan, M.J.; Rae, J.W.B.; Foster, G.L.; Erez, J.; Prentice, K.C.; Kucera, M.; Bostock, H.C.; Martínez-Botí, M.A.; Milton, J.A.; Wilson, P.A.; Marshall, B.J.; Elliott, T. Henehan, M.J. Rae, J.W.B. Foster, G.L. Erez, J. Prentice, K.C. Kucera, M. Bostock, H.C. Martínez-Botí, M.A. Milton, J.A. Wilson, P.A. Marshall, B.J. Elliott, T. earth science/paleoclimate/climate forcing|climate reconstructions|paleoceanography (age,null,null,calendar year before present,null,climate forcing|climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (pH,delta 11B,null,dimensionless,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate forcing|climate reconstructions|paleoceanography (age,null,two standard deviations,calendar year before present,null,climate forcing|climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (delta 11B,Globigerinoides ruber sensu stricto,null,per mil,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,column chemistry) earth science/paleoclimate/paleoceanography (delta 11B,Globigerinoides ruber sensu stricto,two standard deviations,per mil,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,column chemistry) earth science/paleoclimate/climate forcing|paleoceanography (carbon dioxide,bulk atmosphere,null,parts per million,null,climate forcing|paleoceanography,null,null,N,based on planktic foram delta 11B) 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 planktic foram delta 11B) 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 planktic foram delta 11B) 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 (ODP 999A>LATITUDE 12.75>LONGITUDE -78.73) (GeoB1523-1>LATITUDE 3.82>LONGITUDE -41.62) The boron isotope-pH proxy, applied to mixed-layer planktic foraminifera, has great potential for estimating past CO2 levels, which in turn is crucial to advance our understanding of how this greenhouse gas influences Earth's climate. Previous culture experiments have shown that, although the boron isotopic compositions of various planktic foraminifera are pH dependent, they do not agree with the aqueous geochemical basis of the proxy. Here we outline the results of culture experiments on Globigerinoides ruber (white) across a range of pH (~7.5-8.2) and analysed via multicollector inductively-coupled plasma mass spectrometry (MC-ICPMS), and compare these data to core-top and sediment-trap samples to derive a robust new species-specific boron isotope-pH calibration. Consistent with earlier culture studies, we show a reduced pH dependency of the boron isotopic composition of symbiont-bearing planktonic foraminifera compared to borate ion in seawater. We also present evidence for a size fraction effect in the d11B of G. ruber. Finally, we reconstruct atmospheric CO2 concentrations over the last deglacial using our new calibration at two equatorial sites, ODP Site 999A and Site GeoB1523-1. These data provide further grounding for the application of the boron isotope-pH proxy in reconstructions of past atmospheric CO2 levels. STUDY NOTES: Paleo-CO2 derived from boron isotope measurements on marine sediment cores ODP999 and GeoB1523-1 for the last 30,000 years, contributed to the Paleo-pCO2 Database NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Henehan, M.J. Investigator : Rae, J.W.B. Investigator : Foster, G.L. Investigator : Erez, J. Investigator : Prentice, K.C. Investigator : Kucera, M. Investigator : Bostock, H.C. Investigator : Martínez-Botí, M.A. Investigator : Milton, J.A. Investigator : Wilson, P.A. Investigator : Marshall, B.J. Investigator : Elliott, T. 2018-05-09 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/24031 https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/henehan2013boron.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/henehan2013boron.txt https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/henehan2013boron.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/henehan2013boron.txt English https://www.ncdc.noaa.gov/paleo/study/24031 https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/henehan2013boron.xlsx https://www1.ncdc.noaa.gov/pub/data/paleo/climate_forcing/trace_gases/Paleo-pCO2/henehan2013boron.txt Michael J. Henehan, James W.B. Rae, Gavin L. Foster, Jonathan Erez, Katherine C. Prentice, Michal Kucera, Helen C. Bostock, Miguel A. Martínez-Botí, J. Andy Milton, Paul A. Wilson, Brittney J. Marshall, Tim Elliott2013Calibration of the boron isotope proxy in the planktonic foraminifera Globigerinoides ruber for use in palaeo-CO2 reconstructionEarth and Planetary Science Letters364111-12210.1016/j.epsl.2012.12.029https://www.sciencedirect.com/science/article/pii/S0012821X12007157 START YEAR: 30880 cal yr BP * END YEAR: 3915 cal yr BP -78.73 3.82 -41.62 12.75