# 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-ew0408-87jc.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: EW0408-87JC # Location: Gulf of Alaska # Country: # Northernmost_Latitude: 58.8 # Southernmost_Latitude: 58.8 # Easternmost_Longitude: -144.5 # Westernmost_Longitude: -144.5 # Elevation: -3680 #--------------------------------------- # Data_Collection # Collection_Name: EW0408-87JC-eNd # First_Year: 17761 # Last_Year: 711 # Time_Unit: cal yr BP # Core_Length: 14.085 # Notes: This site is co-located with IODP-U1418 #--------------------------------------- # 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 ## Top depth at sample start,,,centimeter,,Paleoceanography,,,N, ## Bot depth at sample end,,,centimeter,,Paleoceanography,,,N, ## Depth_in_Core depth,,,centimeter,,Paleoceanography,,,N,uncorrected depth in core ## 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 Top Bot Depth_in_Core 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 EW0408-87JC 38 40 39 687 711 744 0.512578572 -1.159257648 0.29 NA NA NA EW0408-87JC 52 53 52.5 1092 1329 2032.32 0.512611112 -0.52449453 0.29 0.512612605 -0.495387804 0.29 EW0408-87JC 82 83 82.5 1962 2708 4088.16 0.512596478 -0.809976136 0.29 0.512614719 -0.454131741 0.29 EW0408-87JC 95 96 95.5 2351.84 3305 4733.16 0.512591531 -0.906459254 0.29 NA NA NA EW0408-87JC 106 107 106.5 2698.84 3811 5219.16 0.51259606 -0.818129636 0.29 0.512593661 -0.864920313 0.29 EW0408-87JC 123 124 123.5 3275.84 4592 5890.16 0.51258839 -0.967737137 0.29 NA NA NA EW0408-87JC 139 141 140 3926.68 5349 6462 0.512592201 -0.893391861 0.29 0.512602876 -0.685165941 0.29 EW0408-87JC 160 162 161 4829.84 6314 7110.32 0.512607422 -0.596483268 0.29 NA NA NA EW0408-87JC 177 178 177.5 5774 7073 7598 0.51259224 -0.892641932 0.29 0.512618602 -0.378387834 0.29 EW0408-87JC 194 195 194.5 7093.84 7854 8098 0.512602935 -0.684011784 0.29 NA NA NA EW0408-87JC 208 209 208.5 8462 8503 8538 0.512590321 -0.930078593 0.29 0.51259079 -0.920922033 0.29 EW0408-87JC 217 218 217.5 9112 9167 9213 0.512605872 -0.626725538 0.29 NA NA NA EW0408-87JC 222 223 222.5 9485 9539 9582 0.512612158 -0.504101592 0.29 0.512634727 -0.063849615 0.29 EW0408-87JC 227 229 228 9870 9947 10016 0.512603547 -0.672080724 0.29 NA NA NA EW0408-87JC 231 232 231.5 10161 10209 10247 0.512589881 -0.938652509 0.29 0.512612142 -0.504402864 0.29 EW0408-87JC 234 235 234.5 10385 10431 10469 0.512576941 -1.191076448 0.29 NA NA NA EW0408-87JC 236 237 236.5 10535 10581 10617 0.512577342 -1.183260001 0.29 0.512616671 -0.416070651 0.29 EW0408-87JC 238 239 238.5 10685 10729 10765 0.512576492 -1.199824751 0.29 NA NA NA EW0408-87JC 240 241 240.5 10835 10878 10913 0.512568215 -1.361299754 0.29 0.512618643 -0.377601402 0.29 EW0408-87JC 242 243 242.5 10986 11026 11060 0.512556199 -1.595692608 0.29 NA NA NA EW0408-87JC 244 246 245 11155 11205.5 11231 0.512560881 -1.504352729 0.29 0.512606912 -0.606437335 0.29 EW0408-87JC 249 251 250 11275 11320 11379 0.512544764 -1.818756829 0.29 NA NA NA EW0408-87JC 252 253 252.5 11456 11508 11561.16 0.512548865 -1.738760256 0.29 0.512618231 -0.385633818 0.29 EW0408-87JC 254 256 255 11615 11695 11763 0.512557765 -1.565133068 0.29 NA NA NA EW0408-87JC 266 268 267 11925 11972 12015 0.512570536 -1.316014454 0.29 0.512621242 -0.326889125 0.29 EW0408-87JC 269 270 269.5 12054 12096 12132 0.512581205 -1.107903859 0.29 NA NA NA EW0408-87JC 271 273 272 12178 12226 12270 0.512564963 -1.424721106 0.29 0.512621942 -0.313235819 0.29 EW0408-87JC 274 275 274.5 12327 12356 12384 0.51257826 -1.16534278 0.29 NA NA NA EW0408-87JC 280 282 281 12658 12694 12727 0.512572512 -1.277471442 0.29 0.512637541 -0.008962155 0.29 EW0408-87JC 283 284 283.5 12764 12787 12813 0.512577407 -1.181992755 0.29 NA NA NA EW0408-87JC 288 289 288.5 12945 12970 12996 0.512575628 -1.216680795 0.29 0.51263834 0.006641623 0.29 EW0408-87JC 293 294 293.5 13123 13153 13183 0.512580019 -1.131036492 0.29 NA NA NA EW0408-87JC 300 302 301 13386 13425 13464 0.512577865 -1.173046692 0.29 0.512642508 0.087944363 0.29 EW0408-87JC 304 305 304.5 13488 13522 13560 0.512589302 -0.949958306 0.29 NA NA NA EW0408-87JC 312 313 312.5 13704 13741 13778 0.512584364 -1.046267863 0.29 0.51264184 0.07490815 0.29 EW0408-87JC 318 319 318.5 13862 13903 13947 0.512580637 -1.118979413 0.29 NA NA NA EW0408-87JC 328 330 329 14141 14190 14248 0.512587663 -0.981923704 0.29 0.512639939 0.037822149 0.29 EW0408-87JC 340 342 341 14523 14654 14770 0.512576943 -1.191030579 0.29 NA NA NA EW0408-87JC 347 348 347.5 14677 14797 14908 0.512586408 -1.006397642 0.29 0.51263627 -0.033755865 0.29 EW0408-87JC 359 361 360 14948 15045 15137 0.512593487 -0.868307305 0.29 NA NA NA EW0408-87JC 368 369 368.5 15135 15218 15293 0.512602497 -0.692551838 0.29 0.512680036 0.819988533 0.29 EW0408-87JC 380 382 381 15395 15474 15548 0.512587789 -0.979462102 0.29 NA NA NA EW0408-87JC 397 398 397.5 15690 15753 15813 0.512598987 -0.761027322 0.29 0.512626768 -0.219099567 0.29 EW0408-87JC 420 421 420.5 16084 16134 16186 0.512601958 -0.703064725 0.29 NA NA NA EW0408-87JC 459 460 459.5 16404 16488 16569 0.51261586 -0.431885629 0.29 0.5126166 -0.417458142 0.29 EW0408-87JC 491 492 491.5 16759 16843 16922 0.512638144 0.002814097 0.29 NA NA NA EW0408-87JC 539 540 539.5 16993 17054 17106 0.512658009 0.390311887 0.29 0.512598045 -0.779398677 0.29 EW0408-87JC 922 923 922.5 17181 17231 17280 0.512646895 0.173519548 0.29 NA NA NA EW0408-87JC 1447 1448 1447.5 17704 17761 17818 0.51264385 0.114119431 0.29 0.512607731 -0.590459482 0.29