Ellesmere Island Paleocene Mollusc Stable Isotope Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Ellesmere Island Paleocene Mollusc Stable Isotope Data LAST UPDATE: 7/2006 (Original receipt by WDC Paleo) CONTRIBUTOR: Karen Bice, Woods Hole Oceanographic Institution IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2006-070 SUGGESTED DATA CITATION: Tripati, A., et al. 2006. Ellesmere Island Paleocene Mollusc Stable Isotope Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2006-070. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Tripati, A., J.C. Zachos, L. Marincovich, Jr., and K.L. Bice. 2001. Late Paleocene Arctic coastal climate inferred from molluscan stable and radiogenic isotope ratios. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 170, pp. 101-113. ABSTRACT: Characterizing polar climates during past warm intervals is important for understanding "greenhouse" climate dynamics because high-latitude surface temperatures and precipitation patterns are extremely sensitive to global climatic conditions. Model-data comparisons of high-latitude climates during past warm intervals (Cretaceous-Eocene, Pliocene) are currently at odds. Specifically, simulations of past warm climates produce polar regions characterized by sub-freezing temperatures and significant seasonality, whereas limited fossil proxy data indicate higher mean annual temperatures and low seasonality (i.e. an equable climate). We have constructed a data set to infer northern hemisphere polar marine temperatures during the late Paleocene. Seasonal and mean annual temperature and the oxygen isotopic composition of precipitation are reconstructed for an Arctic coastal setting during the Thanetian (57-58 Ma) using fossil shell stable isotope profiles. We estimate that coastal water temperatures varied between 10 and 15 degrees C during the seasons of growth, presumably spring, summer and fall. These findings support paleontological evidence, implying Northern Hemisphere polar climates were seasonally warm during the late Paleocene. In addition, estuarine fossil oxygen isotope profiles show periodic excursions to low values (as low as -19 per mil VPDB), which indicate seasonal pulses of isotopically-depleted freshwater. GEOGRAPHIC REGION: Ellesmere Island, Canada PERIOD OF RECORD: Danian, late Paleocene. FUNDING SOURCES: National Science Foundation (USA) OCE-9458367 to Zachos, Geological Society of America grant to Tripati. DESCRIPTION: The data consist of oxygen and carbon isotope measurement of carbonate samples microdrilled from sequential growth increments of 1 specimen of the bivalve Arctica ovata. The sample was collected by L. Marincovich, Jr., from the Mount Moore Formation of the Eureka Sound Group on Ellesmere Island, Canada. At the time of publication (1996), the age of the sample was estimated to be Danian. This sample is Field No. 84LM14. DATA: SAMPLE A. Arctica, (Danian) Eureka Sound Grp., Mount Moore Fm., Ellesmere Isl., Canada Field No. 84LM14; shallow marine to estuarine (?) Location: 78.7666 deg. N, approx. 81 deg. W Column 1: Sample ID Column 2: d18O (PDB) Column 3: d13C (PDB) Sample d18O d13C 21 A -11.06 2.12 22 A -11.93 2.16 23 A -12.15 2.06 24 A -12.50 2.07 25 A -12.12 2.11 26 A -12.97 0.90 27 A -12.32 1.44 28 A -13.08 1.08 29 A -11.51 1.59 30 A -13.27 0.24 31 A -15.79 -0.73 32 A -16.82 -0.50 33 A -12.89 0.89 34 A -12.66 1.21 35 A -11.11 1.58 36 A -9.72 2.25 37 A -9.14 2.37 38 A -9.35 2.28 39 A -9.26 2.40 40 A -12.75 1.06 41 A -15.60 -0.02 42 A -13.33 1.79 43 A -13.00 2.15 44 A -14.17 1.55 45 A -13.57 1.88 46 A -12.25 2.09 47 A -10.62 2.08 48 A -11.89 1.70 49 A -10.54 2.22 50 A -10.91 1.77 --- no 51A --- 52 A -10.01 1.87 53 A -10.40 1.31 54 A -10.01 1.54 55 A -10.93 1.19 56 A -11.41 0.78 57 A -15.66 -1.00 58 A -17.20 -0.51 59 A -18.55 -1.02 60 A -16.02 0.14 61 A -9.83 2.03 62 A -13.41 0.27 63 A -12.23 0.50 64 A -11.82 1.51 65 A -11.93 1.97 66 A -11.30 1.26 67 A -10.68 1.84 68 A -12.63 1.46 69 A -10.80 2.10 70 A -10.46 2.03 71 A -14.00 0.86 72 A -12.53 1.44 73 A -7.74 2.79 74 A -14.01 0.86 75 A -14.94 1.06 76 A -25.98 -4.58 77 A -12.06 1.80 78 A -10.54 1.91 79 A -11.04 1.23 80 A -18.69 -1.62 81 A -12.50 0.95 82 A -14.97 -0.27 83 A -11.99 1.14 84 A -10.83 1.65 85 A -11.33 1.31 86 A -12.29 0.76 87 A -12.48 0.87 88 A -11.89 0.66 89 A -10.47 1.71 90 A -9.45 1.71