# EPICA Dome C Ice Core Terminations I and II Air Isotopes and CO2 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:15077 # # Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/epica_domec/edc2013d18oatm.txt # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Ice Cores #-------------------- # Contribution_Date # Date: 2013-09-16 #-------------------- # Title # Study_Name: EPICA Dome C Ice Core Terminations I and II Air Isotopes and CO2 Data #-------------------- # Investigators # Investigators: Landais, A.; Dreyfus, G.B.; Capron, E.; Jouzel, J.; Masson-Delmotte, V.; Roche, D.M.; Prié, F.; Caillon, N.; Chappellaz, J.; Leuenberger, M.; Lourantou, A.; Parrenin, F.; Raynaud, D.; Teste, G. #-------------------- # Description_and_Notes # Description: This dataset gathers published and new data of d15N, d18Oatm and CO2 from the EPICA Dome C ice core over Terminations I and II. # #-------------------- # Publication # Authors: Landais, A., Dreyfus, G.B., Capron, E., Jouzel, J., Masson-Delmotte, V., Roche, D.M., Prié, F., Caillon, N., Chappellaz, J., Leuenberger, M., Lourantou, A., Parrenin, F., Raynaud, D., Teste, G. # Published_Date_or_Year: 2013-12-01 # Published_Title: Two-phase change in CO2, Antarctic temperature and global climate during Termination II # Journal_Name: Nature Geoscience # Volume: 6 # Edition: # Issue: 12 # Pages: 1062-1065 # DOI: 10.1038/ngeo1985 # Online_Resource: http://www.nature.com/ngeo/journal/v6/n12/abs/ngeo1985.html # Full_Citation: # Abstract: The end of the Last Glacial Maximum (Termination I), roughly 20 thousand years ago (ka), was marked by cooling in the Northern Hemisphere, a weakening of the Asian monsoon, a rise in atmospheric CO2 concentrations and warming over Antarctica. The sequence of events associated with the previous glacial-interglacial transition (Termination II), roughly 136 ka, is less well constrained. Here we present high-resolution records of atmospheric CO2 concentrations and isotopic composition of N2 - an atmospheric temperature proxy - from air bubbles in the EPICA Dome C ice core that span Termination II. We find that atmospheric CO2 concentrations and Antarctic temperature started increasing in phase around 136 ka, but in a second phase of Termination II, from 130.5 to 129 ka, the rise in atmospheric CO2 concentrations lagged that of Antarctic temperature unequivocally. We suggest that during this second phase, the intensification of the low-latitude hydrological cycle resulted in the development of a CO2 sink, which counteracted the CO2 outgassing from the Southern Hemisphere oceans over this period. #------------------ # Publication # Authors: Gabrielle B. Dreyfus, Jean Jouzel, Michael L. Bender, Amaëlle Landais, Valérie Masson-Delmotte, Markus Leuenberger # Published_Date_or_Year: 2010-01-01 # Published_Title: Firn processes and d15N: potential for a gas-phase climate proxy # Journal_Name: Quaternary Science Reviews # Volume: 29 # Edition: # Issue: 1-2 # Pages: 28-42 # DOI: 10.1016/j.quascirev.2009.10.012 # Online_Resource: http://www.sciencedirect.com/science/article/pii/S0277379109003576 # Full_Citation: # Abstract: In order to quantify the sequence of events between changes in atmospheric composition and climate changes recorded in ice cores, we must accurately account for the age difference between ice and gas at a given depth. This gas age-ice age difference depends on the age of the ice at the bottom of the firn layer, where the bubbles are closed-off. Firn densification models are used to calculate how this age difference varied in the past, but have an uncertainty on the order of 1000 years for central Antarctic sites. Here we explore the possibility that d15N of N2 is a gas phase proxy of climate, which can be used to synchronize gas and ice records. We present the d15N record from the EPICA Dome C (EDC) ice core covering the last three glacial terminations and five glacial-interglacial cycles between 300 and 800 ka. Previous studies have shown that gravitational settling enriches d15N as a function of the diffusive column height in the firn. If densification models' prediction of deeper firn close-off under glacial conditions is correct, then we would expect heavier d15N during glacial periods, and a negative correlation with temperature. Instead, EDC d15N is positively correlated with the ice deuterium content, a proxy for temperature, as previously reported at Vostok, Dome Fuji, and EPICA Dronning Maud Land. We propose a mechanism that links accumulation rate, firn permeability, and convective mixing in the top meters of the firn to explain this correlation between d15N and ice deuterium content. The tightest correlation is observed over glacial terminations, supporting the idea that d15N is a property in the gas phase that records changes in surface conditions linked to deglacial warming. #------------------ # Publication # Authors: A. Lourantou, J. Chappellaz, J.-M. Barnola, V. Masson-Delmotte, D. Raynaud # Published_Date_or_Year: 2010-08-01 # Published_Title: Changes in atmospheric CO2 and its carbon isotopic ratio during the penultimate deglaciation # Journal_Name: Quaternary Science Reviews # Volume: 29 # Edition: # Issue: 17-18 # Pages: 1983-1992 # DOI: 10.1016/j.quascirev.2010.05.002 # Online_Resource: http://www.sciencedirect.com/science/article/pii/S027737911000137X # Full_Citation: # Abstract: The largest natural increases in atmospheric CO2 concentration as recorded in ice cores occur when the Earth climate abruptly shifts from a glacial to an interglacial state. Open questions remain regarding the processes at play, the sequences of events and their similarities along different glacial-interglacial transitions. Here we provide new combined data of atmospheric CO2 and its carbon isotopic ratio (d13CO2) for the penultimate glacial-interglacial transition (Termination II) from the Antarctic EPICA Dome C ice core. Together with the strongest Antarctic warming, this transition bears the largest CO2 increase (104 ppmv) of the last nine Terminations, ending with an overshoot of 21 ppmv occurring within ~300 y and leading to higher levels than those of the late pre-industrial Holocene. The full CO2 rise is accompanied by an overall decrease of the d13CO2 minimum values, on which three positive excursions are superimposed. Peak-to-peak d13CO2 changes in our record can reach ~1‰. The ice core atmospheric d13CO2 appears more depleted by ~0.2‰ during Termination II compared to Termination I, paralleling a similar carbon isotopic depletion recorded in marine data. During both terminations, most of CO2 and d13CO2 variations are attributed to southern ocean stratification breakdown and decreased efficiency of the biological pump. Compared to Termination I, Termination II ice core data point to different timings of decrease in iron supply and sea-ice extent, suggesting that they could account for distinct patterns of the carbon cycle. #------------------ # Publication # Authors: G.B. Dreyfus, F. Parrenin, B. Lemieux-Dudon, G. Durand, V. Masson-Delmotte, J. Jouzel, J.-M. Barnola, L. Panno, R. Spahni, A. Tisserand, U. Siegenthaler, and M. Leuenberger # Published_Date_or_Year: 2007-06-21 # Published_Title: Anomalous flow below 2700 m in the EPICA Dome C ice core detected using d18O of atmospheric oxygen measurements # Journal_Name: Climate of the Past # Volume: 3 # Edition: # Issue: 2 # Pages: 341-353 # DOI: 10.5194/cp-3-341-2007 # Online_Resource: http://www.clim-past.net/3/341/2007/cp-3-341-2007.html # Full_Citation: # Abstract: While there are no indications of mixing back to 800 000 years in the EPICA Dome C ice core record, comparison with marine sediment records shows significant differences in the timing and duration of events prior to stage 11 (~430 ka, thousands of years before 1950). A relationship between the isotopic composition of atmospheric oxygen (d18O of O2, noted d18Oatm) and daily northern hemisphere summer insolation has been observed for the youngest four climate cycles. Here we use this relationship with new d18O of O2 measurements to show that anomalous flow in the bottom 500 m of the core distorts the duration of events by up to a factor of 2. By tuning d18Oatm to orbital precession we derive a corrected thinning function and present a revised age scale for the interval corresponding to Marine Isotope Stages 11-20 in the EPICA Dome C ice core. Uncertainty in the phasing of d18Oatm with respect to insolation variations in the precession band limits the accuracy of this new agescale to ±6 kyr (thousand of years). The previously reported ~30 kyr duration of interglacial stage 11 is unchanged. In contrast, the duration of stage 15.1 is reduced by a factor of 2, from 31 to 16 kyr. #------------------ # Funding_Agency # Funding_Agency_Name: European Union Seventh Framework programme (FP7/2007-2013) # Grant: 243908 #------------------ # Funding_Agency # Funding_Agency_Name: French ANBR CITRONNIER # Grant: #------------------ # Site_Information # Site_Name: EPICA Dome C # Location: Antarctica # Country: # Northernmost_Latitude: -75.1 # Southernmost_Latitude: -75.1 # Easternmost_Longitude: 123.4 # Westernmost_Longitude: 123.4 # Elevation: 3240 m #------------------ # Data_Collection # Collection_Name: EDC2013d18Oatm # Earliest_Year: 152470 # Most_Recent_Year: 1380 # Time_Unit: Cal Year BP # Core_Length: m # Notes: #------------------ # Chronology: # # # #---------------- # 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) # Termination I d18Oair data 134.5 to 780.2m. Termination II d18Oair data 1388.77 to 1870.02 # ## depth_m depth, , , m, , , , ,N ## d18Oair delta 18O, air, , per mil, , , , ,N #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: depth_m d18Oair 134.5 0.250 146.05 0.117 157.6 0.029 168.05 -0.010 189.5 -0.026 201.05 -0.040 212.05 -0.041 244.5 -0.098 256.05 -0.140 268.15 -0.160 278.05 -0.279 287.95 -0.291 299.5 -0.145 311.05 -0.186 333.05 -0.072 345.925 -0.102 355.6 -0.032 362.75 0.024 376.225 0.187 384.15 0.324 389.425 0.268 395.42 0.386 400.425 0.427 406.275 0.492 411.675 0.541 417.425 0.582 422.685 0.633 428.025 0.635 433.475 0.642 438.995 0.688 447.855 0.767 449.925 0.802 453.395 0.844 455.475 0.862 461.425 0.963 468.825 1.058 470.555 1.039 474.298 1.062 477.925 1.092 481.225 1.088 483.425 1.080 488.375 1.104 490.895 1.100 493.975 1.105 498.445 1.081 499.475 1.049 503.015 1.035 510.425 1.012 516.535 1.021 521.425 0.933 524.315 0.906 526.505 0.952 532.375 0.954 533.062 0.987 537.425 0.940 545.145 0.940 547.825 0.970 549.085 0.999 557.673 0.998 558.945 0.953 561.625 0.965 564.375 0.930 573.295 0.892 577.715 0.899 585.5 0.914 596.5 0.845 602 0.809 607.5 0.795 613 0.711 618.5 0.729 629.5 0.680 635 0.682 640.5 0.686 643.8 0.653 651.5 0.595 655.9 0.607 668 0.455 679 0.531 690 0.520 717.5 0.530 734 0.410 747.2 0.439 750.5 0.447 754.9 0.559 767 0.595 772.5 0.563 780.2 0.489 1388.77 0.056 1394.27 -0.031 1399.77 -0.042 1405.27 0.038 1407.47 0.108 1408.02 -0.052 1410.77 -0.010 1413.52 -0.123 1416.27 0.002 1419.02 -0.015 1421.77 -0.106 1424.52 0.021 1427.27 0.098 1432.77 0.032 1435.52 -0.023 1438.27 -0.148 1441.02 -0.131 1443.77 -0.126 1446.52 0.028 1449.27 -0.062 1452.02 -0.008 1454.77 0.092 1460.27 0.077 1463.02 0.360 1465.77 0.393 1471.27 0.547 1474.02 0.525 1476.77 0.623 1479.52 0.523 1482.27 0.525 1490.52 0.523 1493.27 0.527 1496.02 0.581 1498.77 0.630 1501.52 0.590 1504.27 0.568 1507.02 0.642 1509.77 0.683 1515.27 0.695 1518.02 0.654 1520.77 0.651 1523.52 0.612 1526.27 0.603 1529.02 0.633 1531.77 0.599 1537.27 0.608 1542.77 0.523 1545.52 0.562 1548.27 0.519 1551.02 0.546 1553.77 0.443 1556.52 0.521 1559.27 0.397 1562.02 0.385 1564.77 0.346 1573.02 0.294 1578.52 0.212 1581.27 0.224 1584.02 0.180 1586.77 0.113 1589.52 0.042 1592.27 -0.021 1595.18 -0.069 1597.77 -0.115 1600.52 -0.046 1603.27 -0.169 1606.02 -0.177 1608.77 -0.247 1611.52 -0.238 1614.27 -0.260 1617.02 -0.260 1619.77 -0.235 1622.68 -0.296 1625.27 -0.320 1628.02 -0.311 1630.77 -0.380 1633.52 -0.345 1636.27 -0.394 1639.02 -0.289 1641.77 -0.374 1644.52 -0.348 1647.27 -0.349 1650.21 -0.399 1652.77 -0.385 1655.52 -0.374 1658.27 -0.363 1661.02 -0.304 1663.77 -0.352 1669.27 -0.353 1672.02 -0.272 1674.77 -0.209 1677.52 -0.178 1683.02 -0.044 1685.77 0.022 1691.28 0.122 1694.02 0.173 1696.77 0.203 1699.52 0.353 1702.27 0.394 1705.53 0.457 1707.77 0.500 1710.52 0.588 1713.27 0.667 1716.02 0.731 1718.77 0.865 1721.52 0.895 1724.27 0.909 1727.02 0.956 1729.77 1.016 1732.7 0.978 1735.27 1.036 1738.02 1.011 1740.77 0.998 1743.52 1.078 1746.27 1.173 1749.02 1.145 1751.77 1.084 1754.52 1.140 1760.18 1.072 1762.77 1.053 1765.52 1.123 1768.27 1.063 1773.83 1.017 1776.52 1.065 1779.37 0.991 1782.02 1.044 1784.77 1.021 1784.84 0.993 1787.52 1.003 1787.58 0.969 1790.42 0.975 1793.02 0.978 1795.83 0.975 1801.33 0.915 1804.57 0.934 1806.83 0.923 1809.52 0.890 1812.41 0.852 1815.08 0.803 1817.77 0.797 1817.83 0.776 1823.33 0.657 1828.83 0.647 1834.38 0.644 1839.77 0.558 1845.33 0.559 1867.27 0.728 1870.02 0.689