# Bulk sediment nitrogen isotopes from the northern Peru Margin over the last 25 kyr #----------------------------------------------------------------------- # 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/25430 # Description: NOAA Landing Page # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/bova2018/bova2018-cdh23-14c.txt # Description: NOAA location of the template # # Archive: Paleoceanography # # Dataset_DOI: # # Parameter_Keywords: nitrogen isotopes, carbon isotopes #--------------------------------------- # Contribution_Date # Date: 2018-10-15 #--------------------------------------- # File_Last_Modified_Date # Date: 2018-10-15 #--------------------------------------- # Title # Study_Name: Bulk sediment nitrogen isotopes from the northern Peru Margin over the last 25 kyr #--------------------------------------- # Investigators # Investigators: Bova, Samantha C.; Herbert, Timothy D.; Altabet, Mark A. #--------------------------------------- # Description_Notes_and_Keywords # Description: # Provided Keywords: deglaciation, upwelling, Younger Dryas #--------------------------------------- # Publication # Authors: Bova, S.C., T.D. Herbert, and M.A. Altabet # Published_Date_or_Year: 2018 # Published_Title: Ventilation of northern and southern sources of aged carbon in the eastern equatorial Pacific during the Younger Dryas rise in atmospheric CO2 # Journal_Name: Paleoceanography and Paleoclimatology # Volume: in press # Edition: # Issue: # Pages: # Report_Number: # DOI: # Online_Resource: # Full_Citation: # Abstract: Atmospheric carbon dioxide (CO2) levels rose by ~90 ppmv during the last deglaciation, but the source of this carbon remains unknown. One popular hypothesis suggests carbon accumulated in the deep Southern Ocean, becoming increasingly radiocarbon (14C)-depleted during the last glacial period, and was released into Antarctic Intermediate Water (AAIW) and, subsequently, the atmosphere during deglaciation. Detection of extremely 14C-deplete carbon in the intermediate-depth tropical oceans during periods of atmospheric CO2 rise was initially considered the "smoking gun" for the hypothesis, but attempts to reproduce the anomalies closer to the Southern Ocean source have largely failed. Here, we present new 14C records from four cores recovered at intermediate depths in the eastern equatorial Pacific (EEP). In the context of additional geochemical records, including benthic foraminiferal stable isotopes and sedimentary nitrogen isotopes, we demonstrate that the extreme 14C anomalies observed during the last deglaciation do not reflect the radiocarbon content of AAIW. We show that, although AAIW likely transported modestly 14C-deplete carbon to the EEP subsurface, the extreme 14C signatures might reflect a distinct source of aged carbon arriving from the north, suggesting the North Pacific helped transport deep ocean carbon to the atmosphere during the last deglaciation. In the EEP, additional local hydrothermal inputs of 14C-free carbon near the Galapagos Islands magnified the already low-14C signatures. Finally, regardless of arrival route (North/South Pacific or hydrothermal), 14C-deplete carbon was released from the EEP subsurface during a late deglacial pulse of renewed upwelling, likely contributing to the Younger Dryas rise in atmospheric CO2. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: National Science Foundation # Grant: OCE-1003387 #--------------------------------------- # Site_Information # Site_Name: KNR195-5 CDH23 # Location: Eastern Pacific Ocean # Country: # Northernmost_Latitude: -3.749167 # Southernmost_Latitude: -3.749167 # Easternmost_Longitude: -81.134167 # Westernmost_Longitude: -81.134167 # Elevation: -373 #--------------------------------------- # Data_Collection # Collection_Name: CDH23 14C Bova2018 # First_Year: 14017 # Last_Year: 1102 # Time_Unit: cal yr BP # Core_Length: 17.155 # Notes: #--------------------------------------- # Chronology_Information # Chronology: # # Labcode # depth_top # depth_bottom # mat.dated # 14C.raw # 14C.raw_err # datemeth # reservoir age # calib.14C # calib.14C_97.5% confidence interval lower bound # calib.14C_97.5% confidence interval upper bound # calib_method # calib_curve # # Labcode depth_top depth_bottom mat.dated 14C.raw 14C.raw_err datemeth reservoir age calib.14C calib.14C_97.5% confidence interval lower bound calib.14C_97.5% confidence interval upper bound calib_method calib_curve # OS-77623 30.25 29.25 Neogloboquadrina dutertrei 1680 40 14C AMS 505.086 1102 987 1220 Bchron intcal13 # OS-101833 42.75 41.75 Neogloboquadrina dutertrei 2110 20 14C AMS 501.773 1485 1420 1546 Bchron intcal13 # OS-101834 118.75 117.75 Neogloboquadrina dutertrei 3000 20 14C AMS 504.599 2577 2498 2712 Bchron intcal13 # OS-77579 160.25 159.25 Neogloboquadrina dutertrei 3420 35 14C AMS 509.649 3048 2957 3157 Bchron intcal13 # OS-77576 260.75 259.75 Neogloboquadrina dutertrei 3980 35 14C AMS 509.787 3748 3646 3831 Bchron intcal13 # OS-77575 350.75 349.75 Neogloboquadrina dutertrei 4540 40 14C AMS 493.992 4520 4432 4780 Bchron intcal13 # OS-84123 400.25 399.25 Neogloboquadrina dutertrei 4800 35 14C AMS 508.887 4853 4828 4954 Bchron intcal13 # OS- 77546 460.75 459.75 Neogloboquadrina dutertrei 5290 50 14C AMS 536.799 5500 5333 5585 Bchron intcal13 # OS-84122 500.25 499.25 Neogloboquadrina dutertrei 5720 30 14C AMS 561.623 5920 5782 5982 Bchron intcal13 # OS-84108 550.25 549.25 Neogloboquadrina dutertrei 6230 35 14C AMS 552.944 6456 6401 6544 Bchron intcal13 # OS-84168 600.25 599.25 Neogloboquadrina dutertrei 6510 45 14C AMS 536.911 6810 6692 6922 Bchron intcal13 # OS- 77574 660.75 659.75 Neogloboquadrina dutertrei 6900 40 14C AMS 517.119 7317 7255 7413 Bchron intcal13 # OS-84121 781.25 780.25 Neogloboquadrina dutertrei 7950 40 14C AMS 535.666 8256 8177 8335 Bchron intcal13 # OS- 77580 850.5 849.5 Neogloboquadrina dutertrei 8640 45 14C AMS 548.959 9023 8807 9132 Bchron intcal13 # OS-84120 900.25 899.25 Neogloboquadrina dutertrei 8600 45 14C AMS 552.48 8929 8754 9067 Bchron intcal13 # OS- 77547 1000.5 999.5 Neogloboquadrina dutertrei 9220 60 14C AMS 499.423000000001 9690 9558 9932 Bchron intcal13 # OS-84115 1100.25 1099.25 Neogloboquadrina dutertrei 9920 40 14C AMS 533.578 10619 10519 10701 Bchron intcal13 # OS-84130 1230.25 1229.25 Neogloboquadrina dutertrei 10750 45 14C AMS 547.536 11906 11740 12051 Bchron intcal13 # OS-84124 1285.25 1284.25 Neogloboquadrina dutertrei 10900 50 14C AMS 690.199000000001 11915 11739 12074 Bchron intcal13 # OS- 77573 1360.75 1359.75 Neogloboquadrina dutertrei 11650 55 14C AMS 878.503000000001 12700 12620 12737 Bchron intcal13 # OS-84155 1440.25 1439.25 Neogloboquadrina dutertrei 12000 55 14C AMS 748.744000000001 13110 13037 13229 Bchron intcal13 # OS- 77544 1500.25 1499.25 Neogloboquadrina dutertrei 12200 70 14C AMS 674.796 13364 13225 13468 Bchron intcal13 # OS-84116 1600.25 1599.25 Neogloboquadrina dutertrei 12600 55 14C AMS 649.876 13779 13616 13957 Bchron intcal13 # OS- 77543 1700.25 1699.25 Neogloboquadrina dutertrei 12800 95 14C AMS 652.271000000001 14017 13788 14330 Bchron intcal13 # #--------------------------------------- # 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) ## depth_cm depth,,,centimeter,,,,,N, ## age_calyr age,,,calendar year before present,,,,,N, ## benthic_14Cage age,benthic foraminifer,,radiocarbon year before present,,paleoceanography,,accelerator mass spectrometry,N, ## benthic_14Cage_sd Delta 14C,benthic foraminifer,one standard deviation,radiocarbon year,,,,,N, ## Labcode sample identification,,,,,,,,C,sample identification used by 14C laboratory #------------------------ # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: NA depth_cm age_calyr benthic_14Cage benthic_14Cage_sd labcode 30 1102 1960 20 OS-98324 160 3048 3330 25 OS-98322 260.5 3748 4290 25 OS-98323 350.5 4520 4695 25 OS-98329 500 5920 6370 50 OS-102576 550 6456 6380 50 OS-102573 600 6810 6850 25 OS-102720 900 8929 8990 30 OS-98333 1000.25 9690 9510 30 OS-98332 1100 10619 10150 35 OS-98330 1230 11906 10950 45 OS-102354 1360.5 12700 11575 40 OS-98331 1440 13110 12200 45 OS-98321 1500 13364 12350 40 OS-98328 1700 14017 12950 45 OS-98326