# Antarctic Ice Cores 160KYr Methane 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://hurricane.ncdc.noaa.gov/pls/paleox/f?p=519:1:::::P1_STUDY_ID:14651 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/maud/edml2013d13ch4.txt # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Ice Cores #-------------------- # Contribution_Date # Date: 2013-06-10 #-------------------- # Title # Study_Name: Antarctic Ice Cores 160KYr Methane Isotope Data #-------------------- # Investigators # Investigators: Möller, L.; Sowers, T.A.; Bock, M.; Spahni, R.; Behrens, M.; Schmitt, J.; Miller, H.; Fischer, H. #-------------------- # Description_and_Notes # Description: Carbon and hydrogen isotopic data (d13C and dD) of atmospheric methane from the EPICA Dronning Maud Land and Vostok ice cores. # # We reconstructed atmospheric d13CH4 records using wet extraction techniques and continuous flow gas # chromatography combustion isotope ratio mass spectrometry (GC/C/IRMS) measurements performed on ice core # material from both the European Project for Ice Coring in Antarctica (EPICA) core from Dronning Maud Land # (EDML) and the Vostok cores. At the Alfred Wegener Institute (AWI) we analyzed 151 samples from the EDML core # (including 32 replicates, reproducibility of 0.2 , 1s) to construct a high resolution record between 20 kyr and 75 kyr BP # (1.000 years before present, present referring to 1950 AD) with an average temporal resolution of better than one # sample every 500 years. The period covering the two most pronounced climatic excursions in the Greenland # temperature record during MIS 3 (DO events 7 and 8) were sampled with a resolution of ~200 years. A # complementary record of 79 samples of Vostok ice core material was measured at the Pennsylvania State University # (PSU) covering a time period from 50 kyr to 160 kyr BP with an analytical uncertainty of 0.3 (1s), equivalent to an # average temporal resolution of 1660 years. # The two records were corrected for an instrumental interference from atmospheric krypton, for gravitational settling in # the firn, and a minor inter-laboratory offset of 0.14 . # All d13C values are reported versus Vienna PeeDee Belemnite (VPDB). # We further analyzed 20 samples of EDML ice for dD(CH4) with an external precision of about 2.5 (1s). The # measurements were performed at the University of Bern using a purge and trap extraction coupled to a gas # chromatography pyrolysis isotope ratio mass spectrometer (GC/P/IRMS) and cover the MIS 5/4 transition with an # average resolution of 1.5 kyr in between 54 and 85 kyr BP. The dD(CH4) values are reported with respect to # the international Vienna Standard Mean Ocean Water (VSMOW) scale. # # Note: EDML values above 1009m are reprocessed and recalibrated versions of previously published data (Fischer et al., 2008). # #-------------------- # Publication # Authors: Lars Möller, Todd Sowers, Michael Bock, Renato Spahni, Melanie Behrens, Jochen Schmitt, Heinrich Miller, and Hubertus Fischer # Published_Date_or_Year: 2013-08-25 # Published_Title: Independent variations of CH4 emissions and isotopic composition over the past 160,000 years # Journal_Name: Nature Geoscience # Volume: # Edition: # Issue: # Pages: # DOI: 10.1038/ngeo1922 # Online_Resource: # Full_Citation: # Abstract: During the last glacial cycle, greenhouse gas concentrations fluctuated on decadal and longer timescales. Concentrations of methane, as measured in polar ice cores, show a close connection with Northern Hemisphere temperature variability, but the contribution of the various methane sources and sinks to changes in concentration is still a matter of debate. Here we assess changes in methane cycling over the past 160,000 years by measurements of the carbon isotopic composition d13C of methane in Antarctic ice cores from Dronning Maud Land and Vostok. We find that variations in the d13C of methane are not generally correlated with changes in atmospheric methane concentration, but instead more closely correlated to atmospheric CO2 concentrations. We interpret this to reflect a climatic and CO2-related control on the isotopic signature of methane source material, such as ecosystem shifts in the seasonally inundated tropical wetlands that produce methane. In contrast, relatively stable d13C values occurred during intervals of large changes in the atmospheric loading of methane. We suggest that most methane sources - most notably tropical wetlands - must have responded simultaneously to climate changes across these periods. #------------------ # Publication # Authors: Hubertus Fischer, Melanie Behrens, Michael Bock, Ulrike Richter, Jochen Schmitt, Laetitia Loulergue, Jerome Chappellaz, Renato Spahni, Thomas Blunier, Markus Leuenberger, and Thomas F. Stocker # Published_Date_or_Year: 2008-04-17 # Published_Title: Changing boreal methane sources and constant biomass burning during the last termination # Journal_Name: Nature # Volume: 452 # Edition: # Issue: 7189 # Pages: 864-867 # DOI: 10.1038/nature06825 # Online_Resource: http://www.nature.com/nature/journal/v452/n7189/full/nature06825.html # Full_Citation: # Abstract: Past atmospheric methane concentrations show strong fluctuations in parallel to rapid glacial climate changes in the Northern Hemisphere superimposed on a glacial-interglacial doubling of methane concentrations. The processes driving the observed fluctuations remain uncertain but can be constrained using methane isotopic information from ice cores. Here we present an ice core record of carbon isotopic ratios in methane over the entire last glacial-interglacial transition. Our data show that the carbon in atmospheric methane was isotopically much heavier in cold climate periods. With the help of a box model constrained by the present data and previously published results, we are able to estimate the magnitude of past individual methane emission sources and the atmospheric lifetime of methane. We find that methane emissions due to biomass burning were about 45 Tg methane per year, and that these remained roughly constant throughout the glacial termination. The atmospheric lifetime of methane is reduced during cold climate periods. We also show that boreal wetlands are an important source of methane during warm events, but their methane emissions are essentially shut down during cold climate conditions. #------------------ # Publication # Authors: Benedicte Lemieux-Dudon, Eric Blayo, Jean-Robert Petit, Claire Waelbroeck, Anders Svensson, Catherine Ritz, Jean-Marc Barnola, Bianca Maria Narcisi, Frederic Parrenin # Published_Date_or_Year: 2010-01-01 # Published_Title: Consistent dating for Antarctic and Greenland ice cores # Journal_Name: Quaternary Science Reviews # Volume: 29 # Edition: # Issue: 1-2 # Pages: 8-20 # DOI: 10.1016/j.quascirev.2009.11.010 # Online_Resource: http://www.sciencedirect.com/science/article/pii/S0277379109003734 # Full_Citation: # Abstract: We are hereby presenting a new dating method based on inverse techniques, which aims at calculating consistent gas and ice chronologies for several ice cores. The proposed method yields new dating scenarios simultaneously for several cores by making a compromise between the chronological information brought by glaciological modeling (i.e., ice flow model, firn densification model, accumulation rate model), and by gas and ice stratigraphic constraints. This method enables us to gather widespread chronological information and to use regional or global markers (i.e., methane, volcanic sulfate, Beryllium-10, tephra layers, etc.) to link the core chronologies stratigraphically. Confidence intervals of the new dating scenarios can be calculated thanks to the probabilistic formulation of the new method, which takes into account both modeling and data uncertainties. We apply this method simultaneously to one Greenland (NGRIP) and three Antarctic (EPICA Dome C, EPICA Dronning Maud Land, and Vostok) ices cores, and refine existent chronologies. Our results show that consistent ice and gas chronologies can be derived for depth intervals that are well-constrained by relevant glaciological data. In particular, we propose new and consistent dating of the last deglaciation for Greenland and Antarctic ice and gas records. #------------------ # Publication # Authors: J. Schmitt, B. Seth, M. Bock, C. van der Veen, L. Möller, C.J. Sapart, M. Prokopiou, T. Sowers, T. Röckmann, and H. Fischer # Published_Date_or_Year: 2013 # Published_Title: On the interference of 86Kr2+ during carbon isotope analysis of atmospheric methane using continuous flow combustion - isotope ratio mass spectrometry # Journal_Name: Atmospheric Measurement Techniques Discussions # Volume: 6 # Edition: # Issue: 1 # Pages: 1409-1460 # DOI: 10.5194/amtd-6-1409-2013 # Online_Resource: http://www.atmos-meas-tech-discuss.net/6/1409/2013/amtd-6-1409-2013.html # Full_Citation: # Abstract: Stable carbon isotope analysis of methane (d13C of CH4) on atmospheric samples is one key method to constrain the current and past atmospheric CH4 budget. A frequently applied measurement technique is gas chromatography isotope ratio mass spectrometry coupled to a combustion-preconcentration unit. This report shows that the atmospheric trace gas krypton can severely interfere during the mass spectrometric measurement leading to significant biases in d13C of CH4 if krypton is not sufficiently separated during the analysis. The effect comes about by the lateral tailing of the peak of doubly charged 86Kr in the neighbouring m/z, 44, 45, and 46 Faraday cups. Accordingly, the introduced bias is dependent on the chromatographic separation, the Kr to CH4 mixing ratio in the sample, the mass spectrometer source tuning as well as the detector configuration and can amount to up to several permil in d13C. Apart from technical solutions to avoid this interference we present correction routines to a posteriori remove the bias. #------------------ # Funding_Agency # Funding_Agency_Name: European Research Council (ERC) # Grant: Advanced Grant MATRICs #------------------ # Funding_Agency # Funding_Agency_Name: Schweizerischer Nationalfonds # Grant: #------------------ # Funding_Agency # Funding_Agency_Name: Deutsche Forschungsgemeinschaft # Grant: #------------------ # Funding_Agency # Funding_Agency_Name: European Unions Seventh Framework programme (FP7/2007-2013) # Grant: 243908 #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: 09-44584, 09-68391 #------------------ # Site_Information # Site_Name: EPICA Dronning Maud Land # Location: Antarctica # Country: # Northernmost_Latitude: -75.00 # Southernmost_Latitude: -75.00 # Easternmost_Longitude: 0.0011 # Westernmost_Longitude: 0.0011 # Elevation: 2892 m #------------------ # Data_Collection # Collection_Name: EDMLd13CH4 # Earliest_Year: 78770 # Most_Recent_Year: 9937 # Time_Unit: Cal Year BP # Core_Length: m # Notes: #------------------ # Chronology: # # Tie-points for the manual methane synchronization of Byrd ice core data to EDML ice core gas age scales # # Column 1: tie point No. # Column 2: tie-point EDML depth (m) # Column 3: tie-point gas age ("Unified" gas age, years before 1950 AD, see Lemieux-Dudon et al. 2010, doi:10.1016/j.quascirev.2009.11.010) # Column 4: interpolated EDML CH4 (ppb), (see Schilt et al. 2010, doi:10.1016/j.epsl.2010.09.027) # Column 5: tie-point Byrd depth (m) # Column 6: interpolated Byrd CH4 (ppb), (see Blunier & Brook 2001, doi:10.1126/science.291.5501.109) # # # tie-point EDML depth "Unified" age EDML CH4 Byrd depth Byrd CH4 # (m) years BP (ppb) (m) (ppb) # 1 717.02 11599 609.35 1071.76 574.28 # 2 829.64 14543 529.66 1195.84 543.30 # 3 1070.95 23231 383.60 1446.29 361.95 # 4 1154.20 27748 392.50 1498.37 392.42 # 5 1173.61 28810 419.31 1526.10 417.05 # 6 1233.17 32339 435.59 1595.76 443.86 # 7 1260.48 33728 456.60 1617.35 417.67 # 8 1286.47 35417 467.63 1654.37 449.47 # 9 1337.80 38258 488.11 1716.45 490.03 # 10 1365.07 39433 423.15 1744.35 415.49 # 11 1403.97 41378 443.35 1780.49 422.27 # 12 1436.97 43074 452.35 1806.94 441.63 # 13 1489.88 46719 469.20 1863.57 461.97 # 14 1601.65 53264 491.10 1960.44 488.11 # 15 1627.36 54732 493.91 1973.59 491.04 # 16 1666.48 57333 532.10 2000.30 523.93 # 17 1680.64 58176 538.28 2011.48 533.62 # 18 1688.09 58586 497.84 2017.44 463.90 # 19 1760.37 63448 468.08 2062.90 476.49 # 20 1860.22 71706 470.32 2082.65 460.38 # 21 1914.24 75872 460.21 2100.52 455.18 # 22 1949.26 78706 480.43 2111.69 494.55 # 23 2023.03 85207 550.63 2133.58 546.72 # 24 2065.88 89241 493.35 2139.75 489.08 # # #---------------- # Variables # # Data variables follow (have no #) # 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) # EDML carbon isotopic data of atmospheric methane (d13CH4 ) # Please note that the samples above 1010m are from Fischer et al., 2008, but have here been corrected for Kr interference # and processed similar to the data presented here. Please cite both publications # Column 2 Antarctic unified age scale (see Lemieux-Dudon et al. 2010, doi:10.1016/j.quascirev.2009.11.010) # Column 3: d13CH4 values corrected for machine specific drifts and referenced to VPDB # Column 4: d13C Kr-dev deviations due to mass spectrometer interference with atmospheric krypton (see Schmitt et al. 2013, doi:10.5194/amtd-6-1409-2013) interpolated from Vostok [CH4] data (see Chappellaz et al.,1990 doi:10.1038/345127a0) # Column 5: d13CH4 values corrected for Kr interference # Column 6: d13CH4 values (from column 5) corrected for a constant glacial offset of 0.41 due to gravitational settling in the firn layer depth_m depth, , , m, , , , ,N age_gas_calBPunif age gas unified, , , calendar years before 1950AD, , , Antarctic unified age scale, ,N d13CH4VPDBmc delta13C, CH4, , per mil VPDB, , , corrected for machine specific drifts, ,N d13CVPDBKr-dev delta13C, , , per mil VPDB, , , deviations due to mass spectrometer interference with atmospheric krypton, ,N d13CH4VPDBKr-corr delta13C, CH4, , per mil VPDB, , , corrected for Kr interference, ,N d13CH4VPDBgrav delta13C, CH4, , per mil VPDB, , , corrected for a constant glacial offset of 0.41 due to gravitational settling in the firn layer, ,N d13CH4VPDBstddev delta13C standard deviation, CH4, , per mil VPDB, , , , ,N notes notes, , , , , , Raw data publication, ,N #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: depth_m age_gas_calBPunif d13CH4VPDBmc d13CVPDBKr-dev d13CH4VPDBKr-corr d13CH4VPDBgrav d13CH4VPDBstddev notes 647 9937 -46.1344 0.06 -46.0744 -46.484 Fischer et al., 2008 660 10284 -46.5013 0.16 -46.3413 -46.751 Fischer et al., 2008 672 10592 -46.1051 0.15 -45.9551 -46.365 Fischer et al., 2008 684 10875 -46.0182 0.15 -45.8682 -46.278 0.032 Fischer et al., 2008 684.125 10878 -45.925 0.12 -45.805 -46.215 0.032 Fischer et al., 2008 696 11158 -45.6491 0.12 -45.5291 -45.939 Fischer et al., 2008 709 11448 -45.003 0.18 -44.823 -45.233 Fischer et al., 2008 720.125 11645 -45.5684 0.27 -45.2984 -45.708 Fischer et al., 2008 731 11803 -44.8592 0.13 -44.7292 -45.139 Fischer et al., 2008 743 12029 -44.7787 0.14 -44.6387 -45.049 0.101 Fischer et al., 2008 743.125 12032 -44.5264 0.09 -44.4364 -44.846 0.101 Fischer et al., 2008 757 12393 -44.6705 0.18 -44.4905 -44.901 Fischer et al., 2008 768 12705 -45.7387 0.18 -45.5587 -45.969 Fischer et al., 2008 781 13093 -46.156 0.15 -46.006 -46.416 Fischer et al., 2008 792 13410 -45.9196 0.15 -45.7696 -46.180 0.058 Fischer et al., 2008 792.125 13413 -45.8341 0.18 -45.6541 -46.064 0.058 Fischer et al., 2008 804 13759 -46.0679 0.25 -45.8179 -46.228 Fischer et al., 2008 816 14139 -46.1621 0.22 -45.9421 -46.352 Fischer et al., 2008 828.125 14497 -46.2088 0.29 -45.9188 -46.329 Fischer et al., 2008 839 14786 -44.7614 0.11 -44.6514 -45.061 Fischer et al., 2008 852.125 15121 -45.4936 0.35 -45.1436 -45.554 Fischer et al., 2008 864 15430 -44.0873 0.09 -43.9973 -44.407 Fischer et al., 2008 877 15784 -44.2434 0.27 -43.9734 -44.383 Fischer et al., 2008 888.125 16093 -44.0842 0.29 -43.7942 -44.204 Fischer et al., 2008 913.125 16826 -43.9222 0.32 -43.6022 -44.012 Fischer et al., 2008 924.125 17228 -42.8541 0.31 -42.5441 -42.954 Fischer et al., 2008 934 17633 -43.3115 0.62 -42.6915 -43.102 0.049 Fischer et al., 2008 934.125 17638 -43.0992 0.31 -42.7892 -43.199 0.049 Fischer et al., 2008 961 18770 -42.5783 0.24 -42.3383 -42.748 Fischer et al., 2008 973 19372 -42.8844 0.26 -42.6244 -43.034 0.034 Fischer et al., 2008 973.125 19378 -42.9033 0.21 -42.6933 -43.103 0.034 Fischer et al., 2008 984 19900 -42.6767 0.12 -42.5567 -42.967 Fischer et al., 2008 996 20454 -43.3393 0.28 -43.0593 -43.469 Fischer et al., 2008 1009 21010 -43.454 0.25 -43.204 -43.614 Fischer et al., 2008 1019 21419 -43.2015 0.54 -42.6615 -43.072 1044 22393 -43.4744 0.67 -42.8044 -43.214 1068 23131 -43.751 0.66 -43.091 -43.501 1080 23772 -43.9592 0.81 -43.1492 -43.559 1092 24433 -43.5152 0.7 -42.8152 -43.225 1104 25119 -43.6102 0.72 -42.8902 -43.300 1116 25766 -43.7708 0.69 -43.0808 -43.491 1140 26991 -43.7237 0.69 -43.0337 -43.444 1163 28264 -43.8261 0.61 -43.2161 -43.626 1188 29595 -44.1199 0.72 -43.3999 -43.810 1200 30265 -43.8402 0.59 -43.2502 -43.660 1213 31147 -44.0623 0.57 -43.4923 -43.902 1224 31897 -43.7952 0.36 -43.4352 -43.845 1236 32545 -45.0469 0.55 -44.4969 -44.907 0.026 1236.125 32554 -45.0349 0.59 -44.4449 -44.855 0.026 1248 33330 -44.3318 0.59 -43.7418 -44.152 1260 33718 -44.4459 0.53 -43.9159 -44.326 1268.125 34268 -45.1178 0.82 -44.2978 -44.708 1272 34540 -44.9343 0.68 -44.2543 -44.664 0.335 1272.125 34548 -45.5848 0.66 -44.9248 -45.335 0.335 1277.125 34851 -44.7073 0.56 -44.1473 -44.557 1280.125 35035 -44.8245 0.63 -44.1945 -44.605 1284 35279 -44.4735 0.55 -43.9235 -44.334 0.14 1284.125 35286 -44.7642 0.56 -44.2042 -44.614 0.14 1289.125 35569 -45.6513 0.72 -44.9313 -45.341 1292.125 35712 -45.075 0.71 -44.365 -44.775 1296 35895 -45.3724 0.7 -44.6724 -45.082 0.095 1296.125 35901 -44.9915 0.51 -44.4815 -44.892 0.095 1299.125 36045 -45.4153 0.82 -44.5953 -45.005 1304.125 36304 -44.8415 0.63 -44.2115 -44.622 1308 36501 -45.0899 0.56 -44.5299 -44.940 0.059 1308.125 36508 -45.2672 0.62 -44.6472 -45.057 0.059 1311.125 36674 -45.5815 0.71 -44.8715 -45.282 1316.125 36982 -45.0165 0.53 -44.4865 -44.897 1320 37262 -44.8639 0.45 -44.4139 -44.824 0.221 1320.125 37271 -45.4351 0.58 -44.8551 -45.265 0.221 1325.125 37573 -45.8681 0.43 -45.4381 -45.848 1328 37747 -45.4014 0.39 -45.0114 -45.421 0.063 1328.125 37754 -45.5061 0.62 -44.8861 -45.296 0.063 1332 37969 -45.157 0.52 -44.637 -45.047 0.26 1332.125 37976 -45.6972 0.54 -45.1572 -45.567 0.26 1340 38351 -45.8974 0.54 -45.3574 -45.767 0.194 1340.125 38357 -46.3652 0.62 -45.7452 -46.155 0.194 1344 38516 -45.2525 0.57 -44.6825 -45.093 0.127 1344.125 38521 -45.4961 0.56 -44.9361 -45.346 0.127 1349.125 38718 -45.7706 0.83 -44.9406 -45.351 1352 38834 -45.6553 0.58 -45.0753 -45.485 0.17 1352.125 38839 -45.3948 0.66 -44.7348 -45.145 0.17 1356 38998 -45.1655 0.61 -44.5555 -44.966 0.16 1356.125 39003 -45.5064 0.63 -44.8764 -45.286 0.16 1361.125 39220 -45.9378 0.72 -45.2178 -45.628 1364 39370 -44.2269 0.68 -43.5469 -43.957 0.201 1364.125 39378 -43.8046 0.66 -43.1446 -43.555 0.201 1368 39600 -44.3039 0.67 -43.6339 -44.044 0.345 1368.125 39608 -45.014 0.69 -44.324 -44.734 0.345 1373 39910 -45.4737 0.82 -44.6537 -45.064 1376 40063 -45.3859 0.73 -44.6559 -45.066 0.301 1376.125 40068 -44.7846 0.73 -44.0546 -44.465 0.301 1380 40226 -44.7752 0.66 -44.1152 -44.525 0.517 1380.125 40231 -45.8485 0.7 -45.1485 -45.559 0.517 1385.125 40452 -45.3683 0.79 -44.5783 -44.988 1392 40721 -45.0013 0.64 -44.3613 -44.771 1395.41 40882 -45.735 0.61 -45.125 -45.535 0.332 1395.535 40888 -45.1206 0.66 -44.4606 -44.871 0.332 1403 41318 -44.7944 0.41 -44.3844 -44.794 1407.3 41558 -45.8325 0.78 -45.0525 -45.463 0.126 1407.425 41564 -45.3496 0.55 -44.7996 -45.210 0.126 1416 42018 -45.1223 0.55 -44.5723 -44.982 1418.99 42165 -45.7261 0.7 -45.0261 -45.436 0.019 1419.115 42172 -45.6634 0.6 -45.0634 -45.473 0.019 1427 42552 -45.3968 0.5 -44.8968 -45.307 1431.3 42765 -45.7 0.56 -45.14 -45.550 0.208 1431.425 42772 -46.187 0.63 -45.557 -45.967 0.208 1440 43239 -45.6282 0.65 -44.9782 -45.388 0.11 1440.125 43246 -45.2188 0.46 -44.7588 -45.169 0.11 1444.3 43548 -45.724 0.52 -45.204 -45.614 0.148 1444.425 43560 -46.0607 0.56 -45.5007 -45.911 0.148 1451 44202 -45.8128 0.59 -45.2228 -45.633 1455.3 44555 -46.5876 0.52 -46.0676 -46.478 0.168 1455.425 44564 -47.054 0.65 -46.404 -46.814 0.168 1465 45246 -46.6079 0.57 -46.0379 -46.448 0.08 1465.125 45254 -46.6871 0.49 -46.1971 -46.607 0.08 1466 45309 -47.1401 0.62 -46.5201 -46.930 0.102 1466.125 45316 -46.6362 0.32 -46.3162 -46.726 0.102 1475 45850 -47.2924 0.49 -46.8024 -47.212 1480.425 46169 -47.0248 0.4 -46.6248 -47.035 1487 46554 -46.6736 0.42 -46.2536 -46.664 1492 46834 -46.6599 0.46 -46.1999 -46.610 1499 47190 -47.0273 0.57 -46.4573 -46.867 0.284 1499.125 47196 -46.4095 0.52 -45.8895 -46.300 0.284 1504 47462 -46.3603 0.59 -45.7703 -46.180 1511 47885 -45.9057 0.53 -45.3757 -45.786 1516 48187 -46.26 0.52 -45.74 -46.150 1524.125 48664 -46.2266 0.57 -45.6566 -46.067 1528 48913 -46.0315 0.52 -45.5115 -45.922 1536 49422 -45.9743 0.37 -45.6043 -46.014 1540 49671 -46.9899 0.49 -46.4999 -46.910 1548 50169 -46.9992 0.5 -46.4992 -46.909 1552 50405 -47.0706 0.45 -46.6206 -47.031 1560 50879 -47.0889 0.48 -46.6089 -47.019 1578 51921 -47.525 0.48 -47.045 -47.455 1589 52558 -47.2978 0.47 -46.8278 -47.238 1602 53283 -46.7583 0.46 -46.2983 -46.708 1615 54011 -46.4702 0.52 -45.9502 -46.360 0.051 1615.125 54018 -46.4491 0.6 -45.8491 -46.259 0.051 1627 54711 -46.2069 0.44 -45.7669 -46.177 1639 55482 -46.3175 0.5 -45.8175 -46.228 0.009 1639.125 55490 -46.299 0.5 -45.799 -46.209 0.009 1651 56325 -46.3462 0.45 -45.8962 -46.306 1662 57051 -46.3832 0.41 -45.9732 -46.383 1674 57795 -45.9836 0.41 -45.5736 -45.984 1680 58139 -46.2025 0.5 -45.7025 -46.113 1687 58526 -45.3548 0.41 -44.9448 -45.355 1692 58804 -45.7163 0.48 -45.2363 -45.646 1698 59135 -46.5375 0.57 -45.9675 -46.378 1704 59487 -46.69 0.67 -46.02 -46.430 1709 59800 -45.3349 0.53 -44.8049 -45.215 0.213 1709.125 59807 -45.7907 0.56 -45.2307 -45.641 0.213 1716 60239 -46.1518 0.57 -45.5818 -45.992 1722 60632 -45.3341 0.5 -44.8341 -45.244 1727 60964 -45.391 0.58 -44.811 -45.221 1734 61443 -45.0916 0.52 -44.5716 -44.982 1740 61867 -45.0814 0.61 -44.4714 -44.881 1747 62395 -45.3398 0.54 -44.7998 -45.210 1751 62700 -45.1228 0.51 -44.6128 -45.023 1758 63253 -44.4809 0.5 -43.9809 -44.391 0.147 1758.125 63263 -44.7647 0.49 -44.2747 -44.685 0.147 1765 63812 -45.7399 0.63 -45.1099 -45.520 1770 64212 -45.5524 0.56 -44.9924 -45.402 1775 64619 -45.4822 0.57 -44.9122 -45.322 1782 65202 -44.9646 0.54 -44.4246 -44.835 1788 65728 -45.5775 0.56 -45.0175 -45.428 1800 66715 -46.1511 0.59 -45.5611 -45.971 1806 67216 -46.0766 0.54 -45.5366 -45.947 1812 67745 -46.3815 0.48 -45.9015 -46.312 1819 68344 -46.3793 0.53 -45.8493 -46.259 1824 68761 -46.7261 0.25 -46.4761 -46.886 1830 69245 -47.2358 0.58 -46.6558 -47.066 1837 69853 -47.41 0.56 -46.85 -47.260 1842 70286 -47.8704 0.48 -47.3904 -47.800 1854 71259 -49.2515 0.55 -48.7015 -49.112 1860 71690 -49.0721 0.61 -48.4621 -48.872 0.046 1860.125 71699 -49.0003 0.63 -48.3703 -48.780 0.046 1866 72110 -47.5432 0.47 -47.0732 -47.483 0.452 1866.125 72118 -48.6081 0.63 -47.9781 -48.388 0.452 1872 72519 -48.6272 0.49 -48.1372 -48.547 1878 72973 -48.6763 0.56 -48.1163 -48.526 1890 73989 -49.2659 0.59 -48.6759 -49.086 1902 74968 -49.6878 0.54 -49.1478 -49.558 1926.125 76769 -48.7179 0.44 -48.2779 -48.688 1950 78770 -48.9454 0.48 -48.4654 -48.875