Gulf of Alaska authigenic and bulk sediment neodymium isotope compositions for the past 22,000 years Du, J.; Haley, B.A.; Mix, A.C. Du, J. Haley, B.A. Mix, A.C. earth science/paleoclimate/paleoceanography (depth at sample end,null,null,meter,null,paleoceanography,null,null,N,Depth of the bottom of sample interval on the CCSF_A depth scale) earth science/paleoclimate/paleoceanography (143Nd/144Nd,oxide and hydroxide minerals,null,dimensionless,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,authigenic Fe-Mn oxyhydroxide) earth science/paleoclimate/paleoceanography (notes,null,null,null,null,paleoceanography,null,null,C,Site name) earth science/paleoclimate/paleoceanography (epsilon neodymium,sediment,two standard deviations,epsilon unit,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,long term external reproducibility) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,meter,null,paleoceanography,null,null,N,Depth of the top of sample interval on the CSF_A depth scale) earth science/paleoclimate/paleoceanography (epsilon neodymium,oxide and hydroxide minerals,null,epsilon unit,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,authigenic Fe-Mn oxyhydroxide) earth science/paleoclimate/paleoceanography (143Nd/144Nd,sediment,null,dimensionless,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (depth at sample end,null,null,meter,null,paleoceanography,null,null,N,Depth of the bottom of sample interval on the CSF_A depth scale) earth science/paleoclimate/paleoceanography (age,null,68% confidence interval lower bound,calendar year before present,null,paleoceanography,null,null,N,also 16% quantile age; Bchron bayesian age model) earth science/paleoclimate/paleoceanography (epsilon neodymium,sediment,null,epsilon unit,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (notes,null,null,null,null,paleoceanography,null,null,N,IODP Core number) earth science/paleoclimate/paleoceanography (notes,null,null,null,null,paleoceanography,null,null,N,IODP Section number) earth science/paleoclimate/paleoceanography (depth at sample end,null,null,meter,null,paleoceanography,null,null,N,Depth of the bottom of sample interval on the CCSF_B depth scale) earth science/paleoclimate/paleoceanography (epsilon neodymium,oxide and hydroxide minerals,two standard deviations,epsilon unit,null,paleoceanography,null,multiple collector inductively-coupled plasma mass spectrometry,N,authigenic Fe-Mn oxyhydroxide; long term external reproducibility) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,meter,null,paleoceanography,null,null,N,Depth of the top of sample interval on the CCSF_B depth scale) earth science/paleoclimate/paleoceanography (age,null,null,calendar year before present,null,paleoceanography,null,null,N,median age; Bchron bayesian age model) earth science/paleoclimate/paleoceanography (age,null,68% confidence interval upper bound,calendar year before present,null,paleoceanography,null,null,N,also 84% quantile age; Bchron bayesian age model) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,centimeter,null,paleoceanography,null,null,N,Depth of the top of sample interval in a section) earth science/paleoclimate/paleoceanography (depth at sample end,null,null,centimeter,null,paleoceanography,null,null,N,Depth of the bottom of sample interval in a section) earth science/paleoclimate/paleoceanography (depth at sample start,null,null,meter,null,paleoceanography,null,null,N,Depth of the top of sample interval on the CCSF_A depth scale) earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,null,null,N,uncorrected depth in core) earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,null,null,N,composite depth) earth science/paleoclimate/paleoceanography (notes,null,null,null,null,paleoceanography,null,null,C,IODP Hole number) earth science/paleoclimate/paleoceanography (depth,null,null,meter,null,paleoceanography,null,null,N,Depth of the mid point of sample interval on the CCSF_B depth scale) earth science/paleoclimate/paleoceanography (depth at sample end,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleocean (EW0408-85JC>LATITUDE 59.555>LONGITUDE -144.1535) (IODP U1419>LATITUDE 59.6>LONGITUDE -144.2) (EW0408-87JC>LATITUDE 58.77>LONGITUDE -144.5) (IODP U1418>LATITUDE 58.8>LONGITUDE -144.5) During the last deglaciation (19,000–9,000 years ago), atmospheric CO2 increased by about 80 ppm. Understanding the mechanisms responsible for this change is a central theme of palaeoclimatology, relevant for predicting future CO2 transfers in a warming world. Deglacial CO2 rise hypothetically tapped an accumulated deep Pacific carbon reservoir, but the processes remain elusive as they are underconstrained by existing tracers. Here we report high-resolution authigenic neodymium isotope data in North Pacific sediment cores and infer abyssal Pacific overturning weaker than today during the Last Glacial Maximum but intermittently stronger during steps of deglacial CO2 rise. Radiocarbon evidence suggestive of relatively ‘old’ deglacial deep Pacific water is reinterpreted here as an increase in preformed 14C age of subsurface waters sourced near Antarctica, consistent with movement of aged carbon out of the deep ocean and release of CO2 to the atmosphere during the abyssal flushing events. The timing of neodymium isotope changes suggests that deglacial acceleration of Pacific abyssal circulation tracked Southern Hemisphere warming, sea-ice retreat and increase of mean ocean temperature. The inferred magnitude of circulation changes is consistent with deep Pacific flushing as a significant, and perhaps dominant, control of the deglacial rise of atmospheric CO2. STUDY NOTES: Authigenic neodymium isotope records were generated by leaching non-decarbonated bulk sediments. These records were used to reconstruct North Pacific circulation in the last 22,000 years. Bulk sediment neodymium isotopes were measured by complete microwave digestion of bulk sediments. Provided Keywords: neodymium isotopes, Gulf of Alaska, North Pacific, Deglaciation, Ocean Circulation NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Du, J. Investigator : Haley, B.A. Investigator : Mix, A.C. 2018-07-02 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/24550 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-ew0408-85tc_jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1418.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1419.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-ew0408-87jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-ew0408-85tc_jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1418.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1419.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-ew0408-87jc.txt English https://www.ncdc.noaa.gov/paleo/study/24550 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-ew0408-85tc_jc.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1418.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1419.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-ew0408-87jc.txt Du, Jianghui; Haley, Brian A.; Mix, Alan C.; Walczak, Maureen H.; Praetorius, Summer K.2018Flushing of the deep Pacific Ocean and the deglacial rise of atmospheric CO2 concentrationsNature Geoscience START YEAR: 22165 cal yr BP * END YEAR: 142 cal yr BP -144.5 58.77 -144.1535 59.6