# Southwest Atlantic Deglacial Planktonic and Benthic D14C Data #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. # If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. # # # Online_Resource: http://ncdc.noaa.gov/paleo/study/17675 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/sortor2011/sortor2011plank.txt # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Paleoceanography #-------------------- # Contribution_Date # Date: 2015-01-05 #-------------------- # Title # Study_Name: Southwest Atlantic Deglacial Planktonic and Benthic D14C Data #-------------------- # Investigators # Investigators: Sortor, R.N.; Lund, D.C. #-------------------- # Description_and_Notes # Description: Planktonic and benthic foraminiferal D14C data from southwest Atlantic core KNR159-5-36GGC # for the deglacial period (~18-14 KYrBP). #-------------------- # Publication # Authors: Rachel N. Sortor and David C. Lund # Published_Date_or_Year: 2011-10-01 # Published_Title: No evidence for a deglacial intermediate water D14C anomaly in the SW Atlantic # Journal_Name: Earth and Planetary Science Letters # Volume: 310 # Edition: # Issue: 1-2 # Pages: 65-72 # DOI: 10.1016/j.epsl.2011.07.017 # Online_Resource: http://www.sciencedirect.com/science/article/pii/S0012821X1100433X # Full_Citation: # Abstract: The last deglaciation was characterized by an increase in atmospheric pCO2 and decrease in atmospheric radiocarbon activity. One hypothesis is that these changes were due to out-gassing of 14C-depleted carbon from the abyssal ocean. Reconstructions of foraminiferal D14C from the eastern tropical Pacific, Arabian Sea, and high latitude North Atlantic show that severe depletions in 14C occurred at intermediate water depths during the last deglaciation. It has been suggested that 14C-depleted water from the abyss upwelled in the Southern Ocean and was then carried by Antarctic Intermediate Water (AAIW) to these sites. However, locations in the South Pacific in the direct path of modern-day AAIW do not exhibit the D14C excursion and therefore cast doubt upon the AAIW mechanism (De Pol-Holz et al., 2010 and Rose et al., 2010). Here we evaluate whether or not a deglacial 14C anomaly occurred at intermediate depths in the Southwest Atlantic. We find that the deglacial benthic D14C trend at our site is similar to the atmospheric D14C trend. Our results are also largely consistent with results from U/Th-dated corals at shallower water depths on the Brazil Margin (Mangini et al., 2010). We find no evidence in the southwestern Atlantic of a ~300 per mil decrease in intermediate water D14C from 18 to 14 kyr BP like that observed in the eastern tropical Pacific (Marchitto et al., 2007). When our results are paired with those from the South Pacific, it appears AAIW did not carry a highly 14C-depleted signal during the deglaciation. Another source of carbon is apparently required to explain the intermediate-depth D14C anomalies in the North Atlantic, Indian, and Pacific Oceans. #------------------ # Funding_Agency # Funding_Agency_Name: # Grant: #------------------ # Site_Information # Site_Name: KNR159-5-36GGC # Location: Ocean>Atlantic Ocean>South Atlantic Ocean # Country: # Northernmost_Latitude: -27.5167 # Southernmost_Latitude: -27.5167 # Easternmost_Longitude: -46.4667 # Westernmost_Longitude: -46.4667 # Elevation: -1268 m #------------------ # Data_Collection # Collection_Name: Sortor2011plank # Earliest_Year: 19340 # Most_Recent_Year: 4920 # Time_Unit: Cal. Year BP # Core_Length: m # Notes: #------------------ # Chronology: # # The age model for KNR159-5-36GGC was developed using planktonic 14C ages calibrated with CALIB 6.0 (Reimer et al., 2009). # # #---------------- # Variables # # Data variables follow that are preceded by "##" in columns one and two. # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ##UCIAMS UCIAMS sample number,,,,,,,,N ##depth_cm depth, , , cm, , , , ,N ##Species Species,,,,,,,,C ##age_14cBP 14C age, , , years before present, , , , ,N ##age_14cBPerr 14C age error, , , years, , , , ,N ##age_calBP-1s Age -1s error, , , calendar years before present, , , , CALIB 6.0 - MARINE09,N ##age_calBP+1s Age +1s error, , , calendar years before present, , , , CALIB 6.0 - MARINE09,N ##age_calBP Age, , , calendar years before present, , , , CALIB 6.0 - MARINE09,N ##age_calBPerr Age 1s error, , , calendar years before present, , , , ,N ##notes ,,,,,,,,C # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: # Planktonic radiocarbon results KNR159-5-36GGC. UCIAMS depth_cm Species age_14cBP age_14cBPerr age_calBP-1s age_calBP+1s age_calBP age_calBPerr notes 64768 30.5 G.ruber 4920 15 4965 5463 5214 249 64794 40.5 G.ruber 6395 20 6661 7127 6894 233 64769 40.5 G.ruber 6380 15 6643 7111 6877 234 not sonicated prior to radiocarbon analysis 64770 50.5 G.ruber 7825 15 8062 8495 8279 217 92827 57.5 G.ruber 8445 20 8771 9308 9040 269 64771 60.5 G.ruber 9115 20 9621 10130 9876 255 92828 65.5 G.ruber 9425 20 10034 10528 10281 247 77922 67.5 G.ruber 10425 25 11234 11873 11554 320 64783 70.5 G.ruber 10705 30 11718 12391 12055 337 77923 75.5 G.ruber 10990 25 12179 12669 12424 245 64784 80.5 G.ruber 11485 30 12737 13138 12938 201 77924 85.5 G.ruber 12460 30 13621 14197 13909 288 64785 90.5 G.ruber 12705 35 13943 14655 14299 356 77925 95.5 G.ruber 12275 30 13467 13907 13687 220 64786 100.5 G.ruber 12710 30 13953 14657 14305 352 77926 105.5 G.ruber 13295 35 15027 15970 15499 472 64787 110.5 G.ruber 13465 35 15247 16232 15740 493 77927 115.5 G.ruber 13630 30 15644 16597 16121 477 64788 120.5 G.ruber 13350 40 15115 16097 15606 491 77928 125.5 G.ruber 13765 35 15932 16782 16357 425 64789 130.5 G.ruber 13955 35 16339 16944 16642 303 92829 134.5 G.ruber 14340 70 16796 17242 17019 223 64790 140.5 G.ruber 14045 35 16499 16996 16748 249 77929 142.5 G.ruber 11975 25 13255 13658 13457 202 reversal 92906 146.5 G.ruber 15240 90 17829 18502 18166 337 64791 150.5 G.ruber 15500 70 18046 18573 18310 264 64792 160.5 G.ruber 12055 30 13323 13715 13519 196 reversal 64793 170.5 G.ruber 14365 35 16808 17244 17026 218 reversal 77930 180.5 G.ruber 17510 60 19930 20240 20085 155 92910 182.5 G.ruber 17590 80 20135 20962 20549 414 77931 185.5 G.ruber 18780 70 21611 22172 21892 281 77932 190.5 G.ruber 19340 60 22286 22955 22621 335 77933 200.5 G.ruber 15525 50 18050 18590 18320 270 reversal