# Gulf of Alaska authigenic and bulk sediment neodymium isotope compositions for the past 22,000 years #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # Template Version 3.0 # Encoding: UTF-8 # NOTE: Please cite original publication, online resource and date accessed when using this data. # If there is no publication information, please cite Investigator, title, online resource and date accessed. # # Description/Documentation lines begin with # # Data lines have no # # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/24550 # Description: NOAA Landing Page # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/du2018/du2018-iodp-u1419.txt # Description: NOAA location of the template # # Archive: Paleoceanography # # Dataset_DOI: # # Parameter_Keywords: radiogenic isotope #--------------------------------------- # Contribution_Date # Date: 2018-07-03 #--------------------------------------- # File_Last_Modified_Date # Date: 2018-07-03 #--------------------------------------- # Title # Study_Name: Gulf of Alaska authigenic and bulk sediment neodymium isotope compositions for the past 22,000 years #--------------------------------------- # Investigators # Investigators: Du, Jianghui; Haley, Brian A.; Mix, Alan C. #--------------------------------------- # Description_Notes_and_Keywords # Description: 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 #--------------------------------------- # Publication # Authors: Du, Jianghui; Haley, Brian A.; Mix, Alan C.; Walczak, Maureen H.; Praetorius, Summer K. # Published_Date_or_Year: 2018 # Published_Title: Flushing of the deep Pacific Ocean and the deglacial rise of atmospheric CO2 concentrations # Journal_Name: Nature Geoscience # Volume: # Edition: # Issue: # Pages: # Report_Number: # DOI: 10.1038/s41561-018-0205-6 # Online_Resource: # Full_Citation: # Abstract: 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. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: National Science Foundation # Grant: OCE-1357529 #--------------------------------------- # Site_Information # Site_Name: IODP U1419 # Location: Gulf of Alaska # Country: # Northernmost_Latitude: 59.6 # Southernmost_Latitude: 59.6 # Easternmost_Longitude: -144.2 # Westernmost_Longitude: -144.2 # Elevation: -721 #--------------------------------------- # Data_Collection # Collection_Name: IODP-U1419-eNd # First_Year: 22165 # Last_Year: 16511 # Time_Unit: cal yr BP # Core_Length: 16.97247632 # Notes: This site is co-located with EW0408-85TC/JC #--------------------------------------- # Chronology_Information # Chronology: #--------------------------------------- # Variables # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) ## Site notes,,,dimensionless,,Paleoceanography,,,C,Site name ## H IODP Hole number,,,dimensionless,,Paleoceanography,,,C, ## C IODP Core number,,,dimensionless,,Paleoceanography,,,N, ## S IODP Section number,,,dimensionless,,Paleoceanography,,,N, ## Top depth at sample start,,,centimeter,,Paleoceanography,,,N,Depth of the top of sample interval in a section ## Bot depth at sample end,,,centimeter,,Paleoceanography,,,N,Depth of the bottom of sample interval in a section ## t_csf_a depth at sample start,,,meter,,Paleoceanography,,,N,Depth of the top of sample interval on the CSF_A depth scale ## b_csf_a depth at sample end,,,meter,,Paleoceanography,,,N,Depth of the bottom of sample interval on the CSF_A depth scale ## t_ccsf_a depth at sample start,,,meter,,Paleoceanography,,,N,Depth of the top of sample interval on the CCSF_A depth scale ## b_ccsf_a depth at sample end,,,meter,,Paleoceanography,,,N,Depth of the bottom of sample interval on the CCSF_A depth scale ## t_ccsf_b depth at sample start,,,meter,,Paleoceanography,,,N,Depth of the top of sample interval on the CCSF_B depth scale ## b_ccsf_b depth at sample end,,,meter,,Paleoceanography,,,N,Depth of the bottom of sample interval on the CCSF_B depth scale ## ccsf_b_mid depth,,,meter,,Paleoceanography,,,N,Depth of the mid point of sample interval on the CCSF_B depth scale ## Age_16% age,,68% confidence interval lower bound,calendar year before present,,Paleoceanography,,,N,also 16% quantile age; Bchron bayesian age model ## Age_50% age,,,calendar year before present,,Paleoceanography,,,N,median age; Bchron bayesian age model ## Age_84% age,,68% confidence interval upper bound,calendar year before present,,Paleoceanography,,,N,also 84% quantile age; Bchron bayesian age model ## Authigenic_143Nd/144Nd 143Nd/144Nd,oxide and hydroxide minerals,,dimensionless,,Paleoceanography,,multiple collector inductively-coupled plasma mass spectrometry,N,authigenic Fe-Mn oxyhydroxide ## Authigenic_eNd epsilon neodymium,oxide and hydroxide minerals,,epsilon unit,,Paleoceanography,,multiple collector inductively-coupled plasma mass spectrometry,N,authigenic Fe-Mn oxyhydroxide ## Authigenic_eNd_err epsilon neodymium,oxide and hydroxide minerals,two standard deviations,epsilon unit,,Paleoceanography,,multiple collector inductively-coupled plasma mass spectrometry,N,authigenic Fe-Mn oxyhydroxide; long term external reproducibility ## Bulk_sediment_143Nd/144Nd 143Nd/144Nd,sediment,,dimensionless,,Paleoceanography,,multiple collector inductively-coupled plasma mass spectrometry,N, ## Bulk_sediment_eNd epsilon neodymium,sediment,,epsilon unit,,Paleoceanography,,multiple collector inductively-coupled plasma mass spectrometry,N, ## Bulk_sediment_eNd_err epsilon neodymium,sediment,two standard deviations,epsilon unit,,Paleoceanography,,multiple collector inductively-coupled plasma mass spectrometry,N,long term external reproducibility #------------------------ # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: NA Site H C S Top Bot t_csf_a b_csf_a t_ccsf_a b_ccsf_a t_ccsf_b b_ccsf_b ccsf_b_mid Age_16% Age_50% Age_84% Authigenic_143Nd/144Nd Authigenic_eNd Authigenic_eNd_err Bulk_sediment_143Nd/144Nd Bulk_sediment_eNd Bulk_sediment_eNd_err IODP-U1419 B 1 5 90 93 6.9 6.93 6.9 6.93 5.899707 5.9253579 5.91253245 16443 16511 16585 0.512643903 0.115142561 0.29 NA NA NA IODP-U1419 D 2 1 130 134 6.8 6.84 7.038415 7.078415 6.018055977 6.052257177 6.035156577 16671 16728 16784 0.512652488 0.282612122 0.29 0.512600684 -0.727924469 0.29 IODP-U1419 E 2 4 102 106 14.5 14.54 15.098783 15.13878 12.90991243 12.94411363 12.92701303 17825 17866 17901 0.512664828 0.523326374 0.29 NA NA NA IODP-U1419 E 2 5 140 144 16.4 16.44 16.998783 17.03878 14.53446943 14.56867063 14.55157003 17985 18022 18064 0.512649327 0.220949372 0.29 0.512613882 -0.470466552 0.29 IODP-U1419 E 2 6 25 29 16.8 16.84 17.398783 17.43878 14.87648143 14.91068263 14.89358203 18116 18166 18223 0.512648147 0.197937204 0.29 NA NA NA IODP-U1419 E 2 6 110 114 17.6 17.64 18.198783 18.23878 15.56050543 15.59470663 15.57760603 18481 18532 18579 0.512644485 0.126510603 0.29 0.512626237 -0.229453715 0.29 IODP-U1419 D 3 3 15 19 18.15 18.19 19.545173 19.58517 16.71170927 16.74591047 16.72880987 19329 19438 19524 0.512646284 0.161590042 0.29 NA NA NA IODP-U1419 D 3 3 55 59 18.55 18.59 19.945173 19.98517 17.05372127 17.08792247 17.07082187 19790 19876 19955 0.512649083 0.216203853 0.29 0.512612737 -0.492795304 0.29 IODP-U1419 D 3 3 135 139 19.35 19.39 20.745173 20.78517 17.73774527 17.77194647 17.75484587 20259 20338 20412 0.512659103 0.411657711 0.29 NA NA NA IODP-U1419 D 3 4 135 139 20.86 20.9 22.255173 22.29517 19.02884057 19.06304177 19.04594117 20519 20581 20650 0.512657639 0.383098784 0.29 0.512615612 -0.436728752 0.29 IODP-U1419 D 3 6 15 19 22.56 22.6 23.955173 23.99517 20.48239157 20.51659277 20.49949217 21312.84 21390 21458 0.512632289 -0.111406125 0.29 NA NA NA IODP-U1419 E 3 4 50 54 23.33 23.37 24.845153 24.88515 21.24335117 21.27755237 21.26045177 21517 21574 21633 0.512660847 0.445674785 0.29 0.512627198 -0.210706494 0.29 IODP-U1419 E 3 4 84 88 23.73 23.77 25.245153 25.28515 21.58536317 21.61956437 21.60246377 21668 21719 21769 0.512674903 0.719868815 0.29 NA NA NA IODP-U1419 E 3 5 15 19 24.43 24.47 25.945153 25.98515 22.18388417 22.21808537 22.20098477 21772 21817 21855.16 0.512635941 -0.040155823 0.29 0.512618609 -0.378254426 0.29 IODP-U1419 E 3 5 55 59 24.83 24.87 26.345153 26.38515 22.52589617 22.56009737 22.54299677 21908 21958 22020 0.512639518 0.02961844 0.29 NA NA NA IODP-U1419 E 3 5 95 99 25.23 25.27 26.745153 26.78515 22.86790817 22.90210937 22.88500877 22079 22165 22252 0.51263662 -0.026919436 0.29 0.512625862 -0.236768809 0.29