Central and Southern Atlantic Ocean benthic foraminiferal Mg/Ca, DCO2-3 and BWT Data from core top samples Weldeab, S.; Arce, A.; Kasten, S. Weldeab, S. Arce, A. Kasten, S. Other Reconstruction earth science/paleoclimate/climate reconstructions|paleoceanography (depth at sample end,null,null,centimeter,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (depth at sample start,null,null,centimeter,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/instrumental (carbonate ion,sea water,null,micromole per kilogram,null,instrumental,anomalized,null,N,0 cm sediment depth; the difference between in situ and saturation values (Delta CO2-3)) earth science/paleoclimate/instrumental (carbonate ion,sediment pore water,null,micromole per kilogram,null,instrumental,anomalized,null,N,0-10 cm sediment depth; the difference between in situ and saturation values (Delta CO2-3)) earth science/paleoclimate/paleoceanography (sample identification,null,null,null,null,paleoceanography,null,null,C,core name) earth science/paleoclimate/paleoceanography (notes,null,null,null,null,paleoceanography,null,null,C,null) earth science/paleoclimate/instrumental (carbonate ion,sediment pore water,null,micromole per kilogram,null,instrumental,anomalized,null,N,1-10 cm sediment depth; the difference between in situ and saturation values (Delta CO2-3)) earth science/paleoclimate/instrumental|paleoceanography (longitude,null,null,degree east,null,instrumental|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (longitude,null,null,degree east,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (collection water depth,null,null,meter,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (magnesium/calcium,benthic foraminifer,null,millimole per mole,null,paleoceanography,null,null,N,Globobulimina spp.) earth science/paleoclimate/climate reconstructions|paleoceanography (sample identification,null,null,null,null,climate reconstructions|paleoceanography,null,null,C,core name) earth science/paleoclimate/instrumental (carbonate ion,null,null,micromole per kilogram,null,instrumental,anomalized,null,N,deviation from average Delta CO3-2 values) earth science/paleoclimate/instrumental|paleoceanography (latitude,null,null,degree north,null,instrumental|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (notes,null,null,null,null,climate reconstructions|paleoceanography,null,null,C,species measured) earth science/paleoclimate/climate reconstructions|paleoceanography (latitude,null,null,degree north,null,climate reconstructions|paleoceanography,null,null,N,null) earth science/paleoclimate/climate reconstructions|paleoceanography (sea water temperature,magnesium/calcium,null,degree Celsius,null,climate reconstructions|paleoceanography,null,null,N,bottom water; Calculated using Mg/Ca[mmol/mol]?=?(0.36?±?0.02)*BWT[°C]?+?2.22?±?0.19; r-squared=0.92) earth science/paleoclimate/instrumental|paleoceanography (collection water depth,null,null,meter,null,instrumental|paleoceanography,null,null,N,null) 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 (Central and Southern Atlantic Ocean>LATITUDE >LONGITUDE ) (Gulf of Guinea>LATITUDE >LONGITUDE ) Existing benthic foraminiferal Mg/Ca-temperature calibrations are surrounded by substantial uncertainties mainly due to low temperature sensitivity of Mg/Ca in most benthic foraminifers and the effect of carbonate ion concentration on benthic foraminiferal Mg/Ca. Here we present Mg/Ca analysis of Rose Bengal stained and exceptionally well-preserved tests of the infaunal benthic foraminifer Globobulimina spp. from 39 eastern equatorial Atlantic core top samples. Mg/Ca in Globobulimina spp. varies between 2.5 mmol/mol and 9.1 mmol/mol corresponding to bottom water temperatures (BWT) between 1.8? and 19.1? and ??CO?_(3 pore water)^(2-) between 33.7±4 and -34.3±4 µmol/kg in sediment depths between 1 and 10 cm. Mg/Ca and BWT are linearly correlated with a best fit of Mg/Ca[mmol/mol]=(0.36±0.02)*BWT[°C]+2.22±0.19 (r2=0.92, p: 11*10-20, and n=39). Using total alkalinity and pH data of pore water samples from 64 Atlantic multi-corer sites, we obtained ??CO?_(3 pore water)^(2-)data from the depth habitat range of Globobulimina spp. (= 1 cm = 10 cm below sediment surface). We show that ??CO?_(3 pore water)^(2-) is significantly lower than and linearly co-varies with the ??CO?_3^(2-) of the overlying bottom water: ??CO?_(3 pore water)^(2-)=(0.67±0.05)*??CO?_(3 bottom water)^(2-)-(39.84±1.98); r2=0.75, p: 6*10-20, n=64. We found a Mg/Ca sensitivity of 0.009±0.0044 mmol/mol per µmol/kg ??CO?_(3 pore water)^(2-) and Mg/Ca temperature sensitivity of 0.32 ±0.06 mmol/mol/°C after a correction for the ??CO?_(3 pore water)^(2-) effect. This study provides a robust Mg/Ca-temperature calibration, highlights that ??CO?_(3 pore water)^(2-) is spatially and most likely temporally variable, and contradicts the notion that infaunal foraminiferal Mg/Ca is relatively immune from ??CO?_(3 )^(2-) changes in the overlying bottom water. Furthermore, comparison of down core Mg/Ca data of Cibicides pachyderma and Globobulimina spp. demonstrates that the high temperature sensitivity of Mg/Ca in Globobulimina spp. presents a more robust paleothermometer to reconstruct past changes in the thermal state of the deep ocean. STUDY NOTES: Benthic foramineral Mg/Ca-temperature calibration using Rose Bengel stained core top samples Provided Keywords: pore water chemistry, bottom water calibration NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Weldeab, S. Investigator : Arce, A. Investigator : Kasten, S. 2017-06-26 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/22277 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-bwt.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-dco23pore.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-dco23-bw.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-bwt.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-dco23pore.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-dco23-bw.txt English https://www.ncdc.noaa.gov/paleo/study/22277 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-bwt.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-dco23pore.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/weldeab2016-epsl/weldeab2016-epsl-dco23-bw.txt Weldeab, S., A. Arce, and S. Kasten2016Mg/Ca-DCO2-3 pore-water -temperature calibration for Globobulimina spp.: A sensitive paleothermometer for deep-sea temperature reconstructionEarth and Planetary Science Letters43895-10210.1016/j.epsl.2016.01.009 -54.2583 -44.455 14.005 30.1933