# Southern Ocean 120KYr Nitrogen and Silicon Isotope 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/17917 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/robinson2014b/robinson2014odp1094.txt # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Paleoceanography #-------------------- # Contribution_Date # Date: 2015-01-27 #-------------------- # Title # Study_Name: Southern Ocean 120KYr Nitrogen and Silicon Isotope Data #-------------------- # Investigators # Investigators: Robinson, R.S.; Brzezinski, M.A.; Beucher, C.P.; Horn, M.G.S.; Bedsole, P. #-------------------- # Description_and_Notes # Description: Nitrogen (d15N) and Silicon (d30Si) isotope data measured on diatoms from Southern Ocean sediment cores. #-------------------- # Publication # Authors: Rebecca S. Robinson, Mark A. Brzezinski, Charlotte P. Beucher, Matthew G. S. Horn and Patrick Bedsole # Published_Date_or_Year: 2014-12-01 # Published_Title: The changing roles of iron and vertical mixing in regulating nitrogen and silicon cycling in the Southern Ocean over the last glacial cycle # Journal_Name: Paleoceanography # Volume: 29 # Edition: # Issue: 12 # Pages: 1179-1195 # DOI: 10.1002/2014PA002686 # Online_Resource: http://www.sciencedirect.com/science/article/pii/S0012821X13007280 # Full_Citation: # Abstract: The Southern Ocean plays a critical role in the air-sea CO2 balance through biological and physical mechanisms. Vertical supply of deep waters returns nutrients and CO2 to the surface and stimulates phytoplankton growth. Photosynthesis in the Southern Ocean is limited by iron and only a fraction of the carbon and nutrients that return to the surface are consumed for potential sequestration in the deep sea. Here we present the most spatially extensive data set of silicon and nitrogen isotope measurements from diatom frustules to date to examine the controls on nutrient drawdown during the last glacial period and across the glacial termination in both the Antarctic and Subantarctic zones. The new data confirm existing views that differing silicon and nitrate consumption patterns in the Antarctic zone are likely the result, at least in part, of iron addition during the last glacial maximum (LGM). However, earlier in the glacial, a more coordinated response in the two proxy records, with both reflecting enhanced consumption during episodes of increased iron accumulation and export production, implies a different system response than observed for the LGM. A collapse of the expected equatorward gradient in silicon isotope values and contraction of the nitrogen isotope gradient during the deglaciation suggests that nutrient supply increased not only in the Antarctic Zone, but also in the Subantarctic, perhaps due to enhanced deep mixing locally. Enhanced deep water ventilation across the Southern Ocean likely increased the nutrient content of mode waters during the deglaciation. #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: 00752191 #------------------ # Site_Information # Site_Name: ODP1094 # Location: Ocean>Atlantic Ocean>South Atlantic Ocean # Country: # Northernmost_Latitude: -53.2 # Southernmost_Latitude: -53.2 # Easternmost_Longitude: 5.1 # Westernmost_Longitude: 5.1 # Elevation: m #------------------ # Data_Collection # Collection_Name: Robinson2014ODP1094 # Earliest_Year: 147700 # Most_Recent_Year: 1500 # Time_Unit: Cal. Year BP # Core_Length: m # Notes: #------------------ # Chronology: # # # #---------------- # 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) # ##depth_mbsf depth, , , meters below sea floor, , , , ,N ##depth_m depth, , , common meters, , , , ,N ##age_calkaBP age, , , calendar Kyears before present, , , , ,N ##d15Ndiat delta 15N, diatoms, , per mil v. air, , , , ,N ##d30Sidiat delta 30Si, diatoms, , per mil v. NBS28, , , , ,N ##notes Notes-Sample Description,,,,,,,,C # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: # # depth_mbsf depth_m age_calkaBP d15Ndiat d30Sidiat notes 0.05 0.57 1.5 5.1 1.34 B-001-01W-5-6 0.35 0.87 2.4 4.8 B-001-01W-35-36 0.65 1.17 3.2 5.6 1.31 B-001-01W-65-66 0.95 1.47 4 4.2 B-001-01W-95-96 1.25 1.77 4.9 4.8 1.22 B-001-01W-125-126 1.55 2.07 5.7 4.6 B-001-02W-5-6 1.85 2.37 6.5 4.6 1.15 B-001-02W-35-36 2.15 2.67 7.2 4.2 B-001-02W-65-66 2.45 2.97 7.5 4.2 1.18 B-001-02W-95-96 2.75 3.27 7.9 5.5 B-001-02W-125-126 3.05 3.57 8.2 4.9 1.2 B-001-03W-5-6 3.35 3.87 8.6 4.2 B-001-03W-35-36 3.65 4.17 8.9 5.5 1.29 B-001-03W-65-66 3.95 4.47 9.3 5.2 B-001-03W-95-96 4.25 4.77 9.6 4.9 1.32 B-001-03W-125-126 4.55 5.07 10 4.9 1.26 B-001-04W-5-6 4.9 5.42 10.4 5.1 1.41 B-001-04W-35-36 5.15 5.67 10.7 5.1 1.39 B-001-04W-65-66 5.45 5.97 11 4.9 1.43 B-001-04W-95-96 5.75 6.27 11.4 5.6 1.15 B-001-04W-125-126 6.05 6.57 11.7 5 1.12 B-001-05W-5-6 6.35 6.87 12.3 4.7 1.13 B-001-05W-35-36 6.65 7.17 13.2 5.2 1.11 B-001-05W-65-66 6.95 7.47 14.1 4.6 1.15 B-001-05W-95-96 7.25 7.77 15.1 5.3 1.1 B-001-05W-125-126 7.55 8.07 16.5 4.9 1.27 B-001-06W-5-6 7.85 8.37 17.9 5.3 0.68 B-001-06W-35-36 8.15 8.67 19.3 4.2 0.81 B-001-06W-65-66 8.45 8.97 20.7 4.3 0.76 B-001-06W-95-96 8.75 9.27 22.1 3.6 1.01 B-001-06W-125-126 9.05 9.57 23.5 4.9 0.94 B-001-07W-5-6 9.55 10.57 28.2 3.3 0.95 B-002-01W-5-6 9.85 10.87 29.6 3.9 0.83 B-002-01W-35-36 10.15 11.17 31 4.4 0.93 B-002-01W-65-66 10.45 11.47 32.5 4.4 0.99 B-002-01W-95-96 10.75 11.77 33.9 4 0.87 B-002-01W-125-126 12.15 13.69 43 3.6 0.95 A-002-06W-5-6 12.45 13.99 44.4 3 0.92 A-002-06W-35-36 12.75 14.29 45.9 4.4 1.01 A-002-06W-65-66 13.05 14.59 47.3 4.1 1.01 A-002-06W-95-96 13.35 14.89 48.7 5.7 A-002-06W-125-126 13.6 15.14 49.9 4.3 0.98 A-002-06W-150-151 14.39 16.81 57.9 4.2 1.4 A-003-01W-29-30 15.19 16.91 58.3 4.2 1.32 C-002-05W-29-30 14.69 17.11 59.2 4.5 1.27 A-003-01W-59-60 15.49 17.19 59.6 4.9 1.14 C-002-05W-59-60 14.89 17.31 60.1 4.2 1.13 A-003-01W-89-90 15.79 17.49 60.9 3.7 1.17 C-002-05W-89-90 15.19 17.61 61.4 3 1.21 A-003-01W-119-120 16.09 17.79 62.2 4.5 1.12 C-002-05W-119-120 15.39 17.81 62.3 4.2 1.05 A-003-01W-149-150 16.39 18.09 63.6 3.7 1.24 C-002-05W-149-150 16.69 18.41 69.8 4.1 1.56 C-002-06W-29-30 16.99 18.71 71.7 4.1 1.42 C-002-06W-59-60 17.29 19.01 73.6 3.7 1.67 C-002-06W-89-90 17.59 19.31 75.5 4.6 1.5 C-002-06W-119-120 17.89 19.61 77.4 3.3 1.51 C-002-06W-149-150 18.19 19.89 79.2 3.8 1.4 C-002-07W-29-30 18.49 20.21 82.6 2.9 C-002-07W-59-60 18.61 20.37 85.1 5.3 C-003-01W-21-22 18.91 20.67 89.9 4.7 C-003-01W-51-52 19.21 20.97 94.6 4.3 C-003-01W-81-82 19.51 21.27 99.3 3.3 C-023-01W-111-112 19.81 21.57 104 3.7 C-003-01W-141-142 20.11 21.87 108.8 5.1 C-003-02W-21-22 20.41 22.17 113.5 4.2 C-003-02W-51-52 20.71 22.47 116.5 3.9 C-003-02W-81-82 21.01 22.77 118.1 4.7 C-003-02W-111-112 21.31 23.07 119.7 3.7 C-003-02W-141-142 21.69 24.11 124.4 3.8 A-003-06W-21-22 21.99 24.41 125.2 2.7 A-003-06W-51-52 22.95 24.71 126 4.1 C-003-04A-5-6 23.25 25.01 126.8 4.1 C-003-04A-35-36 23.85 25.61 128.3 5.8 C-003-04A-93-94 24.13 25.89 129.1 3.5 C-003-04A-123-124 24.43 26.19 129.9 5.4 C-003-05A-3-4 24.73 26.49 131.6 4.8 C-003-05A-33-34 25.03 26.79 133.8 4 C-003-05A-63-64 25.33 27.09 135.8 4 C-003-05A-93-94 25.63 27.39 137.8 5 C-003-05A-123-124 25.93 27.69 139.8 4.9 C-003-06A-3-4 26.23 27.99 141.7 5.3 C-003-06A-33-34 26.53 28.29 143.7 4.4 C-003-06A-63-64 26.83 28.59 145.7 4.6 C-003-06A-93-94 27.13 28.89 147.7 3.9 C-003-06A-123-124