# North Atlantic Benthic Foraminifera Stable Isotope Data Over the Past 21,000 Years #----------------------------------------------------------------------- # World Data Center for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # NOTE: Please cite original publication, online resource and date accessed when using these data, # If there is no publication information, please cite investigator, title, online resource and date accessed. # # Online_Resource: http://www.ncdc.noaa.gov/paleo/study/17658 # Online_Resource: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/thornalley2010b/thornalley2010b-12-1k-benth.txt # # Archive: Paleoceanography #-------------------- # Contribution_Date # Date: 2015-01-02 #-------------------- # Title # Study_Name: North Atlantic Benthic Foraminifera Stable Isotope Data Over the Past 21,000 Years #-------------------- # Investigators # Investigators: Thornalley, D.J.R.; Elderfield, H. ; McCave, I.N. #-------------------- # Description_and_Notes # Description: Data collected by David J.R. Thornalley (Univ. of Cambridge); Principal Investigator: I. Nick McCave (Univ. of Cambridge); cruise CD-159, funded by UK RAPID program. # Stable isotope values relative to VPDB standard, run in Godwin Laboratory, Univ. of Cambridge. "Ice-volume corrected" for whole ocean changes using Fairbanks (1989) sea-level curve, assuming a LGM to late Holocene shift of 1‰. # RAPiD-12-1K: Vital effect of -0.24 applied to Melonis d18O data. #-------------------- # Publication # Authors: Thornalley, D.J.R., H. Elderfield, and I.N. McCave # Published_Date_or_Year: 2010 # Published_Title: Intermediate and Deep Water Paleoceanography of the Northern North Atlantic Over the Past 21,000 years # Journal_Name: Paleoceanography # Volume: 25 # Issue: 1 # Report Number: PA1211 # DOI: 10.1029/2009PA001833 # Abstract: Benthic foraminiferal stable isotope records from four high-resolution sediment cores, forming a depth transect between 1237 m and 2303 m on the South Iceland Rise, have been used to reconstruct intermediate and deep water paleoceanographic changes in the northern North Atlantic during the last 21 ka (spanning Termination I and the Holocene). Typically, a sampling resolution of ~100 years is attained. Deglacial core chronologies are accurately tied to North Greenland Ice Core Project (NGRIP) ice core records through the correlation of tephra layers and changes in the percent abundance of Neogloboquadrina pachyderma (sinistral) with transitions in NGRIP. The evolution from the glacial mode of circulation to the present regime is punctuated by two periods with low benthic d13C and d18O values, which do not lie on glacial or Holocene water mass mixing lines. These periods correlate with the late Younger Dryas/Early Holocene (11.5–12.2 ka) and Heinrich Stadial 1 (14.7–16.8 ka) during which time freshwater input and sea-ice formation led to brine rejection both locally and as an overflow exported from the Nordic seas into the northern North Atlantic, as earlier reported by Meland et al. (2008). The export of brine with low d13C values from the Nordic seas complicates traditional interpretations of low d13C values during the deglaciation as incursions of southern sourced water, although the spatial extent of this brine is uncertain. The records also reveal that the onset of the Younger Dryas was accompanied by an abrupt and transient (~200–300 year duration) decrease in the ventilation of the northern North Atlantic. During the Holocene, Iceland-Scotland Overflow Water only reached its modern flow strength and/or depth over the South Iceland Rise by 7–8 ka, in parallel with surface ocean reorganizations and a cessation in deglacial meltwater input to the North Atlantic. #-------------------- # Funding_Agency # Funding_Agency_Name: # Grant: #--------------------- # Site_Information # Site_Name: RAPiD-12-1K # Location: North Atlantic Ocean # Country: # Northernmost_Latitude: 62.0905 # Southernmost_Latitude: 62.0905 # Easternmost_Longitude: -17.819667 # Westernmost_Longitude: -17.819667 # Elevation: -1938 #------------------ # Data_Collection # Collection_Name: RAPiD-12-1K benthics Th2010b # Earliest_Year: 11693 # Most_Recent_Year: 0 # Time_Unit: calyr BP # Core_Length: # Notes: Stable isotope values relative to VPDB standard, run in Godwin Laboratory, Univ. of Cambridge; vital effect of -0.24 applied to Melonis d18O data. "Ice-volume corrected" for whole ocean changes using Fairbanks (1989) sea-level curve, assuming a LGM to late Holocene shift of 1 ‰ # #------------------ # Chronology: # # #------------------ # Variables # # Data line variables format: one variable per line, shortname- 9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # Data line format: tab-delimited text, variable short name as header ## depth_top depth bottom of sample interval,,,cm,,paleoceanography,,,N ## depth_bot depth top of sample interval,,,cm,,paleoceanography,,,N ## depth_cm depth,,,cm,,,,,N ## age_calkaBP age,,,calendar kyr before 1950AD,,,,,N ## numshells number of shells,,, ,,paleoceanography,,,N ## d18Oc.wuell delta 18O,Cibicidoides wuellerstorfi,,per mil VPDB,,paleoceanography,,,N ## d18Oc.wuell-ivc delta 18O,Cibicidoides wuellerstorfi ice-volume corrected,,per mil VPDB,,paleoceanography,,,N ## d13Cc.wuell delta 13C,Cibicidoides wuellerstorfi,,per mil VPDB,,paleoceanography,,,N ## d18Om.barle-.24 delta 18O,Melonis barleanuum,,per mil VPDB,,paleoceanography,vital effect of -0.24 applied,,N ## d18Om.barle-ivc delta 18O,Melonis barleanuum ice-volume corrected,,per mil VPDB,,paleoceanography,,,N ## notes notes,,, ,,,,,C #----------------- # Data: # Missing Value: NaN depth_top depth_bot depth_cm age_calkaBP numshells d18Oc.wuell d18Oc.wuell-ivc d13Cc.wuell d18Om.barle-.24 d18Om.barle-ivc notes 0 1 0.5 0.000 15 2.82 2.82 1.24 NaN NaN 8 9 8.5 0.250 18 2.79 2.78 1.38 NaN NaN 16 17 16.5 0.500 20 2.80 2.79 1.40 NaN NaN 24 25 24.5 0.771 10 2.82 2.80 1.36 NaN NaN number of shells: >10 32 33 32.5 1.064 10 2.80 2.78 1.39 NaN NaN number of shells: >10 40 41 40.5 1.357 10 2.79 2.76 1.42 NaN NaN number of shells: >10 48 49 48.5 1.650 18 2.82 2.79 1.36 NaN NaN 56 57 56.5 1.917 12 2.82 2.78 1.41 NaN NaN 64 65 64.5 2.158 23 2.82 2.78 1.34 NaN NaN 72 73 72.5 2.399 17 2.74 2.70 1.34 NaN NaN 80 81 80.5 2.640 17 2.81 2.76 1.39 NaN NaN 88 89 88.5 2.881 15 2.79 2.74 1.42 NaN NaN 96 97 96.5 3.347 21 2.78 2.71 1.46 NaN NaN 104 105 104.5 3.814 19 2.82 2.74 1.42 NaN NaN 112 113 112.5 4.281 21 2.95 2.86 1.38 NaN NaN 120 121 120.5 4.802 15 2.95 2.85 1.36 NaN NaN 128 129 128.5 5.378 22 2.86 2.75 1.39 NaN NaN 136 137 136.5 5.953 15 2.83 2.71 1.41 NaN NaN 144 145 144.5 6.529 19 2.96 2.83 1.15 NaN NaN 152 153 152.5 6.909 21 3.03 2.90 1.19 NaN NaN 160 161 160.5 7.290 22 3.01 2.87 1.14 NaN NaN 168 169 168.5 7.670 18 2.89 2.74 1.26 NaN NaN 176 177 176.5 8.051 7 2.96 2.81 1.30 NaN NaN 184 185 184.5 8.133 1 2.95 2.80 1.44 NaN NaN 192 193 192.5 8.216 2 3.10 2.95 0.82 NaN NaN 200 201 200.5 8.298 3 2.99 2.84 1.31 NaN NaN 208 209 208.5 8.380 2 2.93 2.78 1.01 NaN NaN 216 217 216.5 8.463 1 2.87 2.72 1.24 NaN NaN 224 225 224.5 8.592 1 2.91 2.74 1.19 NaN NaN 232 233 232.5 8.722 3 3.10 2.93 0.57 NaN NaN 240 241 240.5 8.852 8 3.28 3.10 0.56 NaN NaN 248 249 248.5 8.982 21 3.44 3.26 0.78 NaN NaN 256 257 256.5 9.112 10 2.98 2.78 1.05 NaN NaN 264 265 264.5 9.241 11 3.31 3.11 0.83 NaN NaN 272 273 272.5 9.371 9 3.24 3.03 0.76 NaN NaN 280 281 280.5 9.501 10 3.04 2.82 0.93 NaN NaN 288 289 288.5 9.631 11 3.06 2.83 0.61 NaN NaN 312 313 312.5 9.878 3 3.15 2.90 0.67 NaN NaN 320 321 320.5 9.913 2 3.42 3.17 0.98 NaN NaN 328 329 328.5 9.948 1 3.11 2.85 1.05 NaN NaN 347 348 347.5 10.031 NaN NaN NaN NaN 3.10 2.84 359 360 359.5 10.084 2 2.81 2.54 1.19 NaN NaN 376 377 376.5 10.158 1 2.77 2.50 0.87 NaN NaN 380 381 380.5 10.175 NaN NaN NaN NaN 2.93 2.66 412 413 412.5 10.280 NaN NaN NaN NaN 3.02 2.74 444 445 444.5 10.373 1 3.12 2.84 0.43 NaN NaN 460 461 460.5 10.483 NaN NaN NaN NaN 3.01 2.72 464 465 464.5 10.516 NaN NaN NaN NaN 3.03 2.74 468 469 468.5 10.549 NaN NaN NaN NaN 2.97 2.67 472 473 472.5 10.582 NaN NaN NaN NaN 2.98 2.68 492 493 492.5 10.729 NaN NaN NaN NaN 2.96 2.65 508 509 508.5 10.838 NaN NaN NaN NaN 3.02 2.71 540 541 540.5 11.055 NaN NaN NaN NaN 2.95 2.62 572 573 572.5 11.273 NaN NaN NaN NaN 2.99 2.62 584 585 584.5 11.355 NaN NaN NaN NaN 2.71 2.33 588 589 588.5 11.391 NaN NaN NaN NaN 2.89 2.50 608 609 608.5 11.586 1 3.22 2.79 1.11 NaN NaN 611 612 611.5 11.615 6 2.90 2.47 0.56 NaN NaN 619 620 619.5 11.693 1 2.95 2.52 0.66 NaN NaN