North Iceland Shelf MD99-2269 Holocene Dinoflagellate Assemblage Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: North Iceland Shelf MD99-2269 Holocene Dinoflagellate Assemblage Data LAST UPDATE: 3/2007 (Original receipt by WDC Paleo) CONTRIBUTOR: John Andrews, University of Colorado IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2007-035 SUGGESTED DATA CITATION: Solignac, S., et al. 2007. North Iceland Shelf MD99-2269 Holocene Dinoflagellate Assemblage Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2007-035. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Solignac, S., J. Giraudeau, and A. de Vernal. 2006. Holocene sea surface conditions in the western North Atlantic: Spatial and temporal heterogeneities. Palaeoceanography, 21: 1-16. ABSTRACT: Holocene records of sea surface conditions in the western Nordic seas were obtained from quantitative reconstructions based on dinoflagellate cyst assemblages. Two sediment cores from the east Greenland and the north Iceland shelves provide a detailed account of the long- and short- term dynamics of the opposing flows of Arctic versus Atlantic waters. Both marker species and quantitative reconstructions depict an overall trend toward warmer winter temperatures, saltier surface waters, and decreased sea ice extent. The latter is supported by a close relationship between relative abundances of an Atlantic dinocyst species, Nematosphaeropsis labyrinthus, and ice-rafted debris (IRD) records. We propose that the late Holocene increased IRD delivery in the Denmark Strait region was primarily induced by a combination of less extensive sea ice cover under increased Atlantic water inflow and sustained iceberg calving tied to the readvance of the Greenland ice sheet. Our records thus suggest diminishing polar water supplies throughout the Holocene, although the timing of regime changes differs between the western and eastern sides of the Denmark Strait. Finally, comparison of our records with a core from southern Greenland points to very heterogeneous sea surface conditions in the western North Atlantic, which could be explained by the decoupled dynamics of the two Irminger Current branches. Similarities between the southern Greenland marine record and a continental record nearby suggest a close coupling with atmospheric processes, reminiscent of a North Atlantic Oscillation–like climate pattern. ADDITIONAL REFERENCES FOR MD99-2269: Andersen, C., N. Koc, A. Jennings, and J.T. Andrews. 2004. Nonuniform response of the major surface currents in the Nordic Seas to insolation forcing: Implications for the Holocene climate variability. Paleoceanography, 19: 1-16. doi:10.1029/2002/PA000873, 002004. Andrews, J.T., J. Hardardottir, and J. Stoner. 2002. A very high resolution sediment record from Hunafloaall: Holocene century-scale variability along the N Iceland margin. Nordic Geological Winter Meeting. Andrews, J.T., J. Hardardottir, J.S. Stoner, M.E. Mann, G.B. Kristjansdottir, and N. Koc. 2003. Decadal to millennial-scale periodicities in North Iceland shelf sediments over the last 12,000 cal yrs: long-term North Atlantic oceanographic variability and Solar forcing. Earth and Planetary Science Letters, 210: 453-465. Giraudeau, J., A.E. Jennings, and J.T. Andrews. 2004. Timing and mechanisms of surface and intermediate water circulation changes in the Nordic Seas over the last 10,000 cal years: a view from the North Iceland shelf. Quaternary Science Reviews, Vol. 23, Issues 20-22, pp. 2127-2139, November 2004. *Kristjansdottir, G.B., 2005: Holocene climatic and environmental changes on the Iceland shelf: d18O, Mg/Ca, and tephrochronology of core MD99-2269. PhD, Department of Geological Sciences, University of Colorado at Boulder. Moros, M., J.T. Andrews, D.D. Eberl, and E. Jansen. 2006. The Holocene history of drift ice in the northern North Atlantic: Evidence for different spatial and temporal modes. Palaeoceanography, 21: 1 of 10. doi:10.1029/2005PA001214. *Stoner, J.S., A.E. Jennings, G.B. Kristjansdottir, J.T. Andrews, G. Dunhill, and J. Hardardottir. 2007. A paleomagnetic approach toward refining Holocene radiocarbon based chronostratigraphies: Paleoceanographic records from North Iceland (MD99-2269) and East Greenland (MD99-2322) margins. Palaeoceanography, 22, pages 1 of 23. PA 1209, doi: 10.1029/2006/PA001285. *Note that these two publications use the latest and best age/depth model for the core (see Table of radiocarbon dates and the Stoner et al. (2007) paper). Earlier papers (e.g. Andrews et al., 2003a & b) used a linear regression for depth versus age. Stoner et al. (2007) applied a 5th order polynomial to the data from MD99-2269 and a 9th order polynomial that fits the age/depth data from the combined MD99-2269 and MD99-2322 is included with the radiocarbon data table. The coefficients for these equations are listed in the table of radiocarbon dates. For comparison the tables with the paleomagnetic data have both equations applied to the void corrected depths; in other cases the 9th order polynomial is employed. GEOGRAPHIC REGION: North Iceland Shelf, North Atlantic Ocean PERIOD OF RECORD: 10,280 - 3400 YrBP FUNDING SOURCES: Project GR-240 of the Canadian Foundation for Climate and Atmospheric Sciences, project TARDHOL of the French Programme National d’Etudes de la Dynamique du Climat of CNRS-INSU, Natural Sciences and Engineering Research Council of Canada. DESCRIPTION: Holocene dinoflagellate assemblage data from IMAGES core MD99-2269, North Iceland Shelf (66° 37.53’N, 23° 51.16’W, 365 m water depth). Cruise report: Labeyrie, L., Jansen, E., and Cortijo, E., 2003: Les rapports de campagnes a la mer MD114/IMAGES V. Institut Polaire Francais Paul-Emile Victor, Brest. Same site as: B997-327 Helgadottir, G., 1997: Paleoclimate (0 to >14 ka) of W. and NW Iceland: An Iceland/USA Contribution to P.A.L.E., Cruise Report B9-97. Marine Research Institute of Iceland, Reykjavik. DATA: MD99-2269 Column 1: Depth cm. Column 2: Calibrated age, calendar years BP 1950 Column 3: SST_February Column 4: SSS_February Column 5: SST_August Column 6: SSS_August Column 7: Sea ice cover in months/yr Column 8: Seasonality (SST_Aug-SST_Feb) Column 9: dinocysts/cm3 Column 10: dinocysts/g Depth Age SST_Feb SSS_Feb SST_Aug SSS_Aug Sea ice Seas. dinos/cm3 dinos/g 660 3391 2.422 34.783 6.773 33.839 1.507 4.351 889917 683762 670 3439 2.147 34.680 6.937 33.747 1.113 4.790 470847 337066 680 3485 2.305 34.771 6.388 33.789 1.672 4.083 598024 662924 690 3531 2.406 34.776 6.840 34.116 1.103 4.434 335156 239380 700 3576 2.287 34.711 7.434 33.853 1.145 5.147 295129 409901 710 3620 2.417 34.776 6.821 34.102 1.126 4.404 514372 395671 720 3664 2.287 34.771 6.576 33.952 1.356 4.289 772092 671384 730 3707 3.491 34.810 8.346 34.114 1.086 4.855 645012 390916 740 3749 2.561 34.788 7.267 33.957 1.178 4.706 1135178 630654 745 3770 2.436 34.778 7.031 34.251 1.195 4.595 1290023 405668 750 3791 3.857 34.907 9.434 34.613 0.256 5.577 1022133 555507 755 3811 2.276 34.782 6.803 34.079 1.313 4.527 796179 351255 760 3832 3.349 34.838 8.656 34.348 0.599 5.307 476448 279169 770 3873 2.462 34.654 7.882 33.862 0.813 5.420 401919 251199 785 3934 3.429 34.510 10.083 34.007 0.401 6.654 450298 372147 790 3954 2.544 34.784 7.018 33.907 1.310 4.474 861439 426455 800 3994 1.687 34.674 7.102 34.199 1.652 5.415 631841 619452 810 4034 2.670 34.311 8.782 33.485 1.408 6.112 1281480 739315 820 4073 2.131 34.702 6.947 33.665 1.610 4.816 793450 511903 830 4113 2.514 34.336 9.368 33.463 1.312 6.854 277654 221532 840 4152 2.183 34.776 6.608 34.002 1.456 4.425 767464 599581 850 4192 2.334 34.724 6.879 33.883 1.553 4.545 277654 204157 860 4231 2.404 34.779 6.864 33.782 1.630 4.460 976773 684654 870 4271 4.379 34.445 11.325 33.647 0.481 6.946 265449 170160 890 4351 3.945 34.889 8.535 34.179 1.126 4.590 267865 156765 900 4391 2.469 34.727 7.122 33.985 1.291 4.653 768888 311897 910 4432 4.026 34.911 9.662 34.372 0.814 5.636 307227 177035 920 4473 3.166 34.830 7.445 33.966 1.392 4.279 258760 169003 930 4515 5.292 34.254 13.673 33.559 0.314 8.381 422779 284075 940 4557 2.196 34.642 7.646 33.765 1.423 5.450 670641 372144 955 4622 1.579 34.639 6.485 33.965 2.162 4.906 679184 453758 960 4644 2.361 34.776 6.905 34.053 1.692 4.544 371823 276407 980 4733 2.121 33.901 10.543 32.916 1.045 8.422 402566 243487 990 4778 3.141 33.909 12.153 32.998 0.621 9.012 349495 250032 1000 4824 5.217 34.973 10.414 34.354 0.760 5.197 569547 326650 1010 4872 1.727 34.305 8.216 33.447 1.578 6.489 325710 212285 1020 4919 2.616 34.258 9.786 33.413 1.181 7.170 59187 43842 1030 4968 2.547 34.308 9.663 33.409 1.206 7.116 191098 115119 1040 5018 1.833 34.299 8.747 33.325 1.464 6.914 273840 168000 1050 5069 1.395 34.175 8.669 33.127 1.578 7.274 80962 54704 1060 5120 2.845 34.767 9.050 34.045 1.226 6.205 120238 82923 1070 5173 1.623 34.195 9.323 33.259 1.173 7.700 123219 115158 1080 5226 2.894 34.780 8.549 34.230 1.259 5.655 254008 186770 1090 5281 1.851 34.299 8.767 33.458 1.200 6.916 119880 77342 1100 5336 2.097 34.693 7.904 33.983 1.058 5.807 605143 408881 1110 5392 1.505 34.692 6.819 33.197 1.954 5.314 268618 138463 1120 5450 3.741 34.817 9.397 34.125 1.017 5.656 289304 169184 1130 5508 2.845 34.647 9.088 33.948 0.801 6.243 242057 128073 1140 5567 2.633 34.176 9.159 33.070 0.925 6.526 178733 114572 1150 5627 2.714 34.747 8.010 33.934 1.454 5.296 128878 123921 1160 5689 2.386 34.794 7.379 33.953 1.365 4.993 197816 120619 1170 5751 2.196 34.711 7.475 33.875 1.255 5.279 97235 56205 1180 5814 2.431 34.782 6.918 33.821 1.531 4.487 263924 179540 1190 5877 3.504 34.799 9.125 34.265 0.752 5.621 203529 130467 1200 5942 2.286 34.699 7.459 33.661 1.487 5.173 360992 291123 1210 6008 2.234 34.663 8.139 33.876 1.269 5.905 124703 89074 1220 6074 2.345 33.580 8.699 33.275 1.022 6.354 200388 111327 1230 6141 2.556 34.789 7.281 33.959 1.184 4.725 370853 204891 1240 6209 2.086 34.705 7.313 33.917 1.228 5.227 252291 150173 1250 6277 2.466 34.653 7.919 33.885 0.793 5.453 169847 90344 1260 6346 2.363 34.288 8.886 33.725 0.981 6.523 294562 170267 1270 6416 1.569 34.120 7.964 33.207 1.403 6.395 267169 149758 1280 6486 0.117 32.139 9.314 31.769 2.328 9.197 201833 124588 1290 6557 2.116 33.564 8.463 33.085 1.443 6.347 189679 122374 1300 6628 3.046 34.824 7.726 34.011 1.386 4.680 150930 105990 1310 6700 0.423 32.993 8.987 32.402 1.846 8.564 140692 108782 1320 6771 -0.041 32.632 8.950 32.492 2.104 8.991 156006 107147 1330 6844 1.913 34.351 7.526 33.685 1.581 5.613 194002 125975 1340 6916 0.374 33.053 8.297 32.367 1.947 7.923 508320 287187 1350 6989 0.293 32.871 8.798 32.528 1.925 8.505 252189 141679 1360 7061 1.220 32.861 9.030 32.371 1.591 7.810 236940 127387 1370 7134 3.219 34.832 7.959 34.122 0.919 4.740 385512 184455 1380 7207 1.531 32.987 8.623 32.578 1.339 7.092 205571 128482 1390 7280 -0.765 32.041 9.183 31.761 2.550 9.948 180017 120012 1400 7353 2.984 34.756 8.273 33.933 1.324 5.289 94087 56004 1410 7425 1.575 33.724 7.910 32.852 1.635 6.335 58817 35864 1420 7497 2.068 33.569 8.866 33.074 1.284 6.798 110350 75790 1430 7569 1.752 34.214 7.485 33.252 1.649 5.733 85432 59328 1440 7641 2.065 34.358 8.261 33.155 1.357 6.196 74516 51038 1450 7712 2.010 33.064 10.465 32.705 1.395 8.455 120855 68668 1460 7783 2.450 34.784 7.017 33.993 1.162 4.567 201930 112183 1480 7923 0.495 32.968 9.214 32.366 1.839 8.719 237226 152068 1490 7992 1.131 33.729 7.995 32.992 1.865 6.864 165954 103721 1500 8060 1.568 33.047 9.169 32.838 1.517 7.601 177271 104277 1510 8128 3.056 34.828 7.678 33.971 1.208 4.622 141390 86742 1520 8195 1.716 32.429 9.247 32.283 1.621 7.531 342491 231413 1525 8228 2.587 34.272 7.605 33.433 1.423 5.018 107324 75580 1530 8261 2.468 34.787 7.078 33.990 1.165 4.610 186883 110581 1535 8294 2.367 34.784 6.950 33.984 1.523 4.583 227615 156822 1540 8326 2.476 34.788 7.093 33.974 1.192 4.617 385631 231378 1545 8358 3.204 34.834 7.878 34.141 0.872 4.674 214173 133858 1550 8390 0.767 31.851 9.534 31.688 1.892 8.767 154916 105925 1555 8422 1.518 32.945 8.988 32.521 1.512 7.470 146943 83019 1560 8454 1.329 33.839 9.772 32.669 1.023 8.443 222123 123402 1565 8485 -0.058 31.862 9.540 31.486 2.090 9.598 167304 98414 1570 8516 1.645 34.231 7.694 33.528 1.295 6.049 216428 128826 1575 8547 1.393 34.121 8.097 33.216 1.572 6.704 159851 88316 1580 8577 0.228 32.961 8.946 32.364 2.005 8.718 167150 94435 1585 8608 0.880 31.851 9.547 31.690 1.867 8.667 122453 70782 1590 8638 2.373 34.784 6.959 33.989 1.517 4.586 326599 159317 1595 8667 2.451 34.786 7.069 34.010 1.136 4.618 28540 14270 1600 8697 1.819 34.683 7.492 34.005 1.482 5.673 34325 18430 1605 8726 0.463 32.293 9.467 31.912 1.910 9.004 199163 119259 1610 8755 1.493 33.009 8.991 32.555 1.510 7.498 380172 195965 1615 8783 0.943 32.395 9.151 32.276 1.775 8.208 250471 138637 1620 8812 2.507 34.788 7.095 34.127 1.100 4.588 188850 103197 1625 8840 0.997 33.008 8.541 32.817 1.781 7.544 322056 182986 1630 8867 1.242 26.523 7.731 29.893 2.953 6.489 390377 280847 1635 8895 1.680 33.588 8.170 33.535 1.461 6.490 277654 162371 1640 8922 1.995 31.130 7.674 32.292 1.863 5.679 319607 184744 1645 8949 2.323 34.785 7.013 34.209 1.127 4.690 148274 84728 1650 8975 2.618 34.797 7.315 34.097 1.104 4.697 304352 171950 1655 9002 2.724 34.168 7.556 33.597 1.179 4.832 257878 146893 1660 9027 2.413 34.721 7.651 33.827 1.355 5.238 495506 300306 1665 9053 2.473 34.798 7.454 34.246 0.992 4.981 254770 146420 1670 9078 0.589 32.341 9.496 31.979 1.862 8.907 141539 87250 1675 9103 1.283 32.932 9.038 32.427 1.578 7.755 226581 124952 1680 9128 2.526 34.790 6.945 33.817 1.494 4.419 156219 95722 1685 9152 2.065 34.726 6.521 33.769 1.887 4.456 88517 50581 1690 9176 2.572 34.792 7.187 33.955 1.172 4.615 192707 104166 1695 9200 2.367 34.784 6.824 33.882 1.498 4.457 135541 107147 1700 9224 2.540 34.792 7.233 33.829 1.445 4.693 155749 127663 1705 9247 1.735 33.590 8.190 33.264 1.618 6.455 274490 143963 1710 9269 2.452 34.786 7.059 33.996 1.162 4.607 187044 115459 1715 9292 2.618 34.796 7.307 34.094 1.098 4.689 243329 149281 1720 9314 2.421 34.786 6.858 33.858 1.485 4.437 147726 93794 1730 9358 1.261 33.775 9.943 32.563 1.037 8.682 192610 88516 1740 9400 2.454 34.791 7.049 33.879 1.409 4.595 211444 113072 1750 9441 0.044 31.987 9.539 31.724 2.329 9.495 198504 103387 1760 9481 2.185 33.333 10.571 32.879 1.009 8.386 123142 82369 1770 9519 2.457 34.787 7.087 34.002 1.152 4.630 310662 184918 1780 9557 1.872 34.275 7.653 33.536 1.646 5.781 274237 160185 1790 9593 1.241 30.585 7.775 31.605 2.511 6.534 190280 124250 1800 9628 2.442 34.789 7.006 33.866 1.418 4.564 227310 154483 1810 9663 2.003 34.754 7.133 34.142 1.477 5.130 371629 186748 1820 9696 2.172 34.780 7.076 34.114 1.247 4.904 217585 134311 1830 9728 1.012 34.665 5.474 33.838 2.384 4.462 831182 324681 1840 9759 2.442 34.788 6.992 33.863 1.420 4.550 320370 192222 1850 9790 2.188 34.771 6.723 34.014 1.347 4.535 767594 334707 1860 9819 2.316 34.773 6.663 33.972 1.299 4.347 299012 153182 1870 9848 2.479 34.799 7.462 34.257 0.975 4.983 350241 186119 1885 9889 1.217 34.138 7.851 33.400 1.665 6.634 580938 337303 1890 9903 2.053 34.753 6.813 33.904 1.610 4.760 371985 192738 1900 9929 2.406 34.732 8.010 34.074 0.992 5.604 214292 138253 1910 9955 2.057 34.759 7.188 34.162 1.441 5.131 818723 432424 1920 9980 1.709 34.215 7.973 33.901 1.254 6.264 285047 168667 1930 10005 1.450 33.633 9.161 33.316 1.318 7.711 396434 213903 1940 10029 0.603 32.309 9.495 31.975 1.867 8.892 363849 217874 1950 10053 1.556 34.180 7.481 33.644 1.801 5.925 293262 203654 1960 10076 2.135 34.705 7.303 33.708 1.584 5.168 745750 503885 1970 10099 2.132 34.036 8.069 33.585 1.460 5.937 536862 337649 1980 10122 1.659 34.669 7.021 33.815 1.712 5.362 257435 141968 1990 10145 2.175 34.715 7.755 34.102 1.152 5.580 217852 198047 2000 10168 2.161 33.015 8.632 33.064 1.275 6.471 567513 366137 2010 10190 1.800 33.574 8.569 33.178 0.962 6.769 520601 327938 2020 10213 2.471 34.208 7.576 33.775 1.436 5.105 446875 354663 2030 10235 2.145 34.760 7.320 34.240 1.243 5.175 281468 223387 2040 10258 2.521 34.132 8.283 33.604 1.270 5.762 389298 290521 2050 10280 2.513 33.694 9.018 33.717 1.013 6.505 217852 207478