Author: "Loulergue L" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Loulergue L"' showing total 44 results

Start Over Author "Loulergue L"

44 results on '"Loulergue L"'

1. Robustness of a plasma acceleration based Free Electron Laser

Author: Labat, M., Loulergue, L., Andre, T., Andriyash, I., Ghaith, A., Khojoyan, M., Marteau, F., Valleau, M., Briquez, F., and Benabderrahmane, C.
Subjects: Physics - Accelerator Physics
Abstract: Laser Plasma Accelerators (LPA) can sustain GeV/m accelerating fields offering outstanding new possibilities for compact applications. Despite the impressive recent developments, the LPA beam quality is still significantly lower than in the conventional radio-frequency accelerators, which is an issue in the cases of demanding applications such as Free Electron Lasers (FELs). If the electron beam duration is below few tens of femtosecond keeping pC charges, the mrad level divergence and few percent energy spread are particularly limiting. Several concepts of transfer line were proposed to mitigate those intrinsic properties targetting undulator radiation applications. We study here the robustness of the chromatic matching strategy for FEL amplification at 200~nm in a dedicated transport line, and analyze its sensitivity to several parameters. We consider not only the possible LPA source jitters, but also various realistic defaults of the equipment such as magnetic elements misalignements or focussing strength errors, unperfect undulator fields, etc...
Published: 2018
Full Text: View/download PDF

2. Orbital and Millennial Antarctic Climate Variability over the Past 800,000 Years

Author: Jouzel, J., Masson-Delmotte, V., Cattani, O., Dreyfus, G., Falourd, S., Hoffmann, G., Minster, B., Nouet, J., Barnola, J. M., Chappellaz, J., Fischer, H., Gallet, J. C., Johnsen, S., Leuenberger, M., Loulergue, L., Luethi, D., Oerter, H., Parrenin, F., Raisbeck, G., Raynaud, D., Schilt, A., Schwander, J., Selmo, E., Souchez, R., Spahni, R., Stauffer, B., Steffensen, J. P., Stenni, B., Stocker, T. F., Tison, J. L., Werner, M., and Wolff, E. W.
Published: 2007
Full Text: View/download PDF

3. Synchronising EDML and NorthGRIP ice cores using δ 18O of atmospheric oxygen (δ 18O atm) and CH 4 measurements over MIS5 (80–123 kyr)

Author: Capron, E., Landais, A., Lemieux-Dudon, B., Schilt, A., Masson-Delmotte, V., Buiron, D., Chappellaz, J., Dahl-Jensen, D., Johnsen, S., Leuenberger, M., Loulergue, L., and Oerter, H.
Published: 2010
Full Text: View/download PDF

4. One-to-one coupling of glacial climate variability in Greenland and Antarctica

Author: Barbante, C., Barnola, J.-M., Becagli, S., Beer, J., Bigler, M., Boutron, C., Blunier, T., Castellano, E., Cattani, O., Chappellaz, J., Dahl-Jensen, D., Debret, M., Delmonte, B., Dick, D., Falourd, S., Faria, S., Federer, U., Fischer, H., Freitag, J., Frenzel, A., Fritzsche, D., Fundel, F., Gabrielli, P., Gaspari, V., Gersonde, R., Graf, W., Grigoriev, D., Hamann, I., Hansson, M., Hoffmann, G., Hutterli, M. A., Huybrechts, P., Isaksson, E., Johnsen, S., Jouzel, J., Kaczmarska, M., Karlin, T., Kaufmann, P., Kipfstuhl, S., Kohno, M., Lambert, F., Lambrecht, Anja, Lambrecht, Astrid, Landais, A., Lawer, G., Leuenberger, M., Littot, G., Loulergue, L., Luthi, D., Maggi, V., Marino, F., Masson-Delmotte, V., Meyer, H., Miller, H., Mulvaney, R., Narcisi, B., Oerlemans, J., Oerter, H., Parrenin, F., Petit, J.-R., Raisbeck, G., Raynaud, D., Rothlisberger, R., Ruth, U., Rybak, O., Severi, M., Schmitt, J., Schwander, J., Siegenthaler, U., Siggaard-Andersen, M.-L., Spahni, R., Steffensen, J. P., Stenni, B., Stocker, T. F., Tison, J.-L., Traversi, R., Udisti, R., Valero-Delgado, F., van den Broeke, M. R., van de Wal, R. S. W., Wagenbach, D., Wegner, A., Weiler, K., Wilhelms, F., Winther, J.-G., and Wolff, E.
Abstract: Author(s): EPICA Community Members; EPICA Community Members; C. Barbante [1, 2]; J.-M. Barnola [3]; S. Becagli [4]; J. Beer [5]; M. Bigler [6, 7]; C. Boutron [3]; T. Blunier [6]; [...]
Published: 2006
Full Text: View/download PDF

5. Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core

Author: Tison, Jean-Louis, de Angelis, M., Littot, G., Wolff, Eric, Ficher, Hubertus, Hansson, M., Bigler, Matthias, Udisti, Roberto, Wegner, Anna, Jouzel, Jean, Stenni, Barbara, Johnsen, Sigfus J., Masson-Delmotte, Valerie, Landais, Amaelle, Lipenkov, V., Loulergue, L., Barnola, J.-M., Petit, J. R., Delmonte, Barbara, Dreyfus, G., Dahl-Jensen, Dorthe, Durand, G., Bereiter, Bernhard, Schilt, A., Spahni, Renato, Pol, K., Lorrain, R., Souchez, R., Samyn, D., Tison, Jean-Louis, de Angelis, M., Littot, G., Wolff, Eric, Ficher, Hubertus, Hansson, M., Bigler, Matthias, Udisti, Roberto, Wegner, Anna, Jouzel, Jean, Stenni, Barbara, Johnsen, Sigfus J., Masson-Delmotte, Valerie, Landais, Amaelle, Lipenkov, V., Loulergue, L., Barnola, J.-M., Petit, J. R., Delmonte, Barbara, Dreyfus, G., Dahl-Jensen, Dorthe, Durand, G., Bereiter, Bernhard, Schilt, A., Spahni, Renato, Pol, K., Lorrain, R., Souchez, R., and Samyn, D.
Abstract: An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges in the near future, it is essential to judge how deep these records remain unaltered, since the proximity of the bedrock is likely to interfere both with the recorded temporal sequence and the ice properties. In this paper, we present a multiparametric study (δD-δ18Oice, δ18Oatm, total air content, CO2, CH4, N2O, dust, high-resolution chemistry, ice texture) of the bottom 60 m of the EPICA (European Project for Ice Coring in Antarctica) Dome C ice core from central Antarctica. These bottom layers were subdivided into two distinct facies: the lower 12 m showing visible solid inclusions (basal dispersed ice facies) and the upper 48 m, which we will refer to as the "basal clean ice facies". Some of the data are consistent with a pristine paleoclimatic signal, others show clear anomalies. It is demonstrated that neither large-scale bottom refreezing of subglacial water, nor mixing (be it internal or with a local basal end term from a previous/initial ice sheet configuration) can explain the observed bottom-ice properties. We focus on the high-resolution chemical profiles and on the available remote sensing data on the subglacial topography of the site to propose a mechanism by which relative stretching of the bottom-ice sheet layers is made possible, due to the progressively confining effect of subglacial valley sides. This stress field change, combined with bottom-ice temperature close to the pressure melting point, induces accelerated migration recrystallization, which results in spatial chemical sorting of the impurities, depending on their state (dissolved vs. solid) and if they are involved or not in salt formation. This chemical sorting effect is responsible for the progressive build-up of the visible solid aggregates that therefore mainly originate "from within", and not from inco
Published: 2015

6. Can we retrieve a clear paleoclimatic signal from the deeper part of the EPICA Dome C ice core?

Author: Tison, J.-L., de Angelis, M., Littot, G., Wolff, E., Fischer, H., Hansson, M., Bigler, M., Udisti, R., Wegner, A., Jouzel, J., Stenni, B., Johnsen, S., Masson-Delmontte, V., Landais, A., Lipenkov, V., Loulergue, L., Barnola, J.-M., Petit, J.-R., Delmonte, B., Dreyfuss, G., Dahl-Jensen, D., Durand, G., Bereiter, B., Schilt, A., Spahni, R., Pol, K., Lorrain, R., Souchez, R., Samyn, D., Tison, J.-L., de Angelis, M., Littot, G., Wolff, E., Fischer, H., Hansson, M., Bigler, M., Udisti, R., Wegner, A., Jouzel, J., Stenni, B., Johnsen, S., Masson-Delmontte, V., Landais, A., Lipenkov, V., Loulergue, L., Barnola, J.-M., Petit, J.-R., Delmonte, B., Dreyfuss, G., Dahl-Jensen, D., Durand, G., Bereiter, B., Schilt, A., Spahni, R., Pol, K., Lorrain, R., Souchez, R., and Samyn, D.
Abstract: An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges in the near future, it is essential to judge how deep these records remain unaltered, since the proximity of the bedrock is likely to interfere both with the recorded temporal sequence and the ice properties. In this paper, we present a multiparametric study (δD-δ18Oice, δ18Oatm, total air content, CO2, CH4, N2O, dust, high resolution chemistry, ice texture) of the bottom 60m of the EPICA Dome C ice core from central Antarctica. These bottom layers have been subdivided in two sections: the lower 12m showing visible solid inclusions (basal ice) and the 48m above which we refer to as “deep ice”. Some of the data are consistent with a pristine paleoclimatic signal, others show clear anomalies. It is demonstrated that neither large scale bottom refreezing of subglacial water, nor mixing (be it internal or with a local basal end-term from a previous/ initial ice sheet configuration) can explain the observed bottom ice properties. We focus on the high-resolution chemical profiles and on the available remote sensing data on the subglacial topography of the site to propose a mechanism by which relative stretching of the bottom ice sheet layers is made possible, due to the progressively confining effect of subglacial valley sides. This stress field change, combined with bottom ice temperature close to the pressure melting point, induces accelerated migration recrystallization, which results in spatial chemical sorting of the impurities, depending on their state (dissolved vs. solid) and if they are involved or not in salt formation. This chemical sorting effect is responsible for the progressive build-up of the visible solid aggregates that therefore mainly originate “from within”, and not from incorporation processes of allochtone material at the ice–bedrock interface. We also discuss how th
Published: 2015

7. Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core

Author: Tison, J.-L., de Angelis, M., Littot, G., Wolff, E., Fischer, H., Hansson, Margareta, Bigler, M., Udisti, R., Wegner, A., Jouzel, J., Stenni, B., Johnsen, S., Masson-Delmotte, V., Landais, A., Lipenkov, V., Loulergue, L., Barnola, J. -M., Petit, J. -R., Delmonte, B., Dreyfus, G., Dahl-Jensen, D., Durand, G., Bereiter, B., Schilt, A., Spahni, R., Pol, K., Lorrain, R., Souchez, R., Samyn, D., Tison, J.-L., de Angelis, M., Littot, G., Wolff, E., Fischer, H., Hansson, Margareta, Bigler, M., Udisti, R., Wegner, A., Jouzel, J., Stenni, B., Johnsen, S., Masson-Delmotte, V., Landais, A., Lipenkov, V., Loulergue, L., Barnola, J. -M., Petit, J. -R., Delmonte, B., Dreyfus, G., Dahl-Jensen, D., Durand, G., Bereiter, B., Schilt, A., Spahni, R., Pol, K., Lorrain, R., Souchez, R., and Samyn, D.
Abstract: An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges in the near future, it is essential to judge how deep these records remain unaltered, since the proximity of the bedrock is likely to interfere both with the recorded temporal sequence and the ice properties. In this paper, we present a multiparametric study (delta D-delta O-18(ice), delta O-18(atm), total air content, CO2, CH4, N2O, dust, high-resolution chemistry, ice texture) of the bottom 60 m of the EPICA (European Project for Ice Coring in Antarctica) Dome C ice core from central Antarctica. These bottom layers were subdivided into two distinct facies: the lower 12 m showing visible solid inclusions (basal dispersed ice facies) and the upper 48 m, which we will refer to as the basal clean ice facies. Some of the data are consistent with a pristine paleoclimatic signal, others show clear anomalies It is demonstrated that neither large-scale bottom refreezing of subglacial water, nor mixing (be it internal or with a local basal end term from a previous/initial ice sheet configuration) can explain the observed bottom-ice properties. We focus on the high-resolution chemical profiles and on the available remote sensing data on the subglacial topography of the site to propose a mechanism by which relative stretching of the bottom-ice sheet layers is made possible, due to the progressively confining effect of subglacial valley sides. This stress field change, combined with bottom-ice temperature close to the pressure melting point, induces accelerated migration recrystallization, which results in spatial chemical sorting of the impurities, depending on their state (dissolved vs. solid) and if they are involved or not in salt formation. This chemical sorting effect is responsible for the progressive build-up of the visible solid aggregates that therefore mainly originate from within, a
Published: 2015
Full Text: View/download PDF

8. Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core

Author: Tison, J. -L., de Angelis, M., Littot, G., Wolff, E., Fischer, H., Hansson, M., Bigler, M., Udisti, R., Wegner, A., Jouzel, J., Stenni, B., Johnsen, S., Masson-Delmotte, V., Landais, A., Lipenkov, V., Loulergue, L., Barnola, J. -M., Petit, J. -R., Delmonte, B., Dreyfus, G., Dahl-Jensen, D., Durand, G., Bereiter, B., Schilt, A., Spahni, R., Pol, K., Lorrain, R., Souchez, R., Samyn, D., Tison, J. -L., de Angelis, M., Littot, G., Wolff, E., Fischer, H., Hansson, M., Bigler, M., Udisti, R., Wegner, A., Jouzel, J., Stenni, B., Johnsen, S., Masson-Delmotte, V., Landais, A., Lipenkov, V., Loulergue, L., Barnola, J. -M., Petit, J. -R., Delmonte, B., Dreyfus, G., Dahl-Jensen, D., Durand, G., Bereiter, B., Schilt, A., Spahni, R., Pol, K., Lorrain, R., Souchez, R., and Samyn, D.
Published: 2015

9. Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core

Author: Tison, J.-L., primary, de Angelis, M., additional, Littot, G., additional, Wolff, E., additional, Fischer, H., additional, Hansson, M., additional, Bigler, M., additional, Udisti, R., additional, Wegner, A., additional, Jouzel, J., additional, Stenni, B., additional, Johnsen, S., additional, Masson-Delmotte, V., additional, Landais, A., additional, Lipenkov, V., additional, Loulergue, L., additional, Barnola, J.-M., additional, Petit, J.-R., additional, Delmonte, B., additional, Dreyfus, G., additional, Dahl-Jensen, D., additional, Durand, G., additional, Bereiter, B., additional, Schilt, A., additional, Spahni, R., additional, Pol, K., additional, Lorrain, R., additional, Souchez, R., additional, and Samyn, D., additional
Published: 2015
Full Text: View/download PDF

10. Supplementary material to "Can we retrieve a clear paleoclimatic signal from the deeper part of the EPICA Dome C ice core?"

Author: Tison, J.-L., primary, de Angelis, M., additional, Littot, G., additional, Wolff, E., additional, Fischer, H., additional, Hansson, M., additional, Bigler, M., additional, Udisti, R., additional, Wegner, A., additional, Jouzel, J., additional, Stenni, B., additional, Johnsen, S., additional, Masson-Delmotte, V., additional, Landais, A., additional, Lipenkov, V., additional, Loulergue, L., additional, Barnola, J.-M., additional, Petit, J.-R., additional, Delmonte, B., additional, Dreyfus, G., additional, Dahl-Jensen, D., additional, Durand, G., additional, Bereiter, B., additional, Schilt, A., additional, Spahni, R., additional, Pol, K., additional, Lorrain, R., additional, Souchez, R., additional, and Samyn, D., additional
Published: 2015
Full Text: View/download PDF

11. Can we retrieve a clear paleoclimatic signal from the deeper part of the EPICA Dome C ice core?

Author: Tison, J.-L., primary, de Angelis, M., additional, Littot, G., additional, Wolff, E., additional, Fischer, H., additional, Hansson, M., additional, Bigler, M., additional, Udisti, R., additional, Wegner, A., additional, Jouzel, J., additional, Stenni, B., additional, Johnsen, S., additional, Masson-Delmotte, V., additional, Landais, A., additional, Lipenkov, V., additional, Loulergue, L., additional, Barnola, J.-M., additional, Petit, J.-R., additional, Delmonte, B., additional, Dreyfus, G., additional, Dahl-Jensen, D., additional, Durand, G., additional, Bereiter, B., additional, Schilt, A., additional, Spahni, R., additional, Pol, K., additional, Lorrain, R., additional, Souchez, R., additional, and Samyn, D., additional
Published: 2015
Full Text: View/download PDF

12. What caused the glacial/interglacial CH4 changes? Carbon isotopic constraints on methane sources from the EDML ice core

Author: Fischer, Hubertus, Behrens, Melanie, Bock, Michael, Salzer, U., Schmitt, Jochen, Loulergue, L., Chappellaz, J., Spahni, R., Blunier, T., Leuenberger, M., and Stocker, T.
Published: 2007

13. Synchronising EDML and NorthGRIP ice cores using δ18O of atmospheric oxygen (δ18Oatm ) and CH4 measurements over MIS5 (80-123 kyrs BP)

Author: Capron, E., Landais, A., Lemieux-Dudon, B., Schilt, A., Masson-Delmotte, V., Buiron, D., Chappellaz, J., Dahl-Jensen, D., Johnsen, S., Leuenberger, M., Loulergue, L., Oerter, Hans, Capron, E., Landais, A., Lemieux-Dudon, B., Schilt, A., Masson-Delmotte, V., Buiron, D., Chappellaz, J., Dahl-Jensen, D., Johnsen, S., Leuenberger, M., Loulergue, L., and Oerter, Hans
Published: 2010

14. Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period

Author: Capron, E., Landais, A., Chappellaz, J., Schilt, A., Buiron, D., Dahl-jensen, D., Johnsen, S. J., Jouzel, J., Lemieux-dudon, B., Loulergue, L., Leuenberger, M., Masson-delmotte, V., Meyer, H., Oerter, H., Stenni, B., Capron, E., Landais, A., Chappellaz, J., Schilt, A., Buiron, D., Dahl-jensen, D., Johnsen, S. J., Jouzel, J., Lemieux-dudon, B., Loulergue, L., Leuenberger, M., Masson-delmotte, V., Meyer, H., Oerter, H., and Stenni, B.
Abstract: Since its discovery in Greenland ice cores, the millennial scale climatic variability of the last glacial period has been increasingly documented at all latitudes with studies focusing mainly on Marine Isotopic Stage 3 (MIS 3; 28-60 thousand of years before present, hereafter ka) and characterized by short Dansgaard-Oeschger (DO) events. Recent and new results obtained on the EPICA and NorthGRIP ice cores now precisely describe the rapid variations of Antarctic and Greenland temperature during MIS 5 (73.5-123 ka), a time period corresponding to relatively high sea level. The results display a succession of abrupt events associated with long Greenland InterStadial phases (GIS) enabling us to highlight a sub-millennial scale climatic variability depicted by (i) short-lived and abrupt warming events preceding some GIS (precursor-type events) and (ii) abrupt warming events at the end of some GIS (rebound-type events). The occurrence of these sub-millennial scale events is suggested to be driven by the insolation at high northern latitudes together with the internal forcing of ice sheets. Thanks to a recent NorthGRIP-EPICA Dronning Maud Land (EDML) common timescale over MIS 5, the bipolar sequence of climatic events can be established at millennial to sub-millennial timescale. This shows that for extraordinary long stadial durations the accompanying Antarctic warming amplitude cannot be described by a simple linear relationship between the two as expected from the bipolar seesaw concept. We also show that when ice sheets are extensive, Antarctica does not necessarily warm during the whole GS as the thermal bipolar seesaw model would predict, questioning the Greenland ice core temperature records as a proxy for AMOC changes throughout the glacial period.
Published: 2010
Full Text: View/download PDF

15. Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period

Author: Capron, Emilie, Landais, A., Chappellaz, J., Schilt, A., Buiron, D., Dahl-Jensen, Dorthe, Johnsen, Sigfus Johann, Jouzel, J., Lemieux-Dudon, B., Loulergue, L., Leuenberger, M., Masson-Delmotte, V., Meyer, H., Oerter, H., Stenni, B., Capron, Emilie, Landais, A., Chappellaz, J., Schilt, A., Buiron, D., Dahl-Jensen, Dorthe, Johnsen, Sigfus Johann, Jouzel, J., Lemieux-Dudon, B., Loulergue, L., Leuenberger, M., Masson-Delmotte, V., Meyer, H., Oerter, H., and Stenni, B.
Abstract: Since its discovery in Greenland ice cores, the millennial scale climatic variability of the last glacial period has been increasingly documented at all latitudes with studies focusing mainly on Marine Isotopic Stage 3 (MIS 3; 28–60 thousand of years before present, hereafter ka) and characterized by short Dansgaard-Oeschger (DO) events. Recent and new results obtained on the EPICA and NorthGRIP ice cores now precisely describe the rapid variations of Antarctic and Greenland temperature during MIS 5 (73.5–123 ka), a time period corresponding to relatively high sea level. The results display a succession of abrupt events associated with long Greenland InterStadial phases (GIS) enabling us to highlight a sub-millennial scale climatic variability depicted by (i) short-lived and abrupt warming events preceding some GIS (precursor-type events) and (ii) abrupt warming events at the end of some GIS (rebound-type events). The occurrence of these sub-millennial scale events is suggested to be driven by the insolation at high northern latitudes together with the internal forcing of ice sheets. Thanks to a recent NorthGRIP-EPICA Dronning Maud Land (EDML) common timescale over MIS 5, the bipolar sequence of climatic events can be established at millennial to sub-millennial timescale. This shows that for extraordinary long stadial durations the accompanying Antarctic warming amplitude cannot be described by a simple linear relationship between the two as expected from the bipolar seesaw concept. We also show that when ice sheets are extensive, Antarctica does not necessarily warm during the whole GS as the thermal bipolar seesaw model would predict, questioning the Greenland ice core temperature records as a proxy for AMOC changes throughout the glacial period.
Published: 2010

16. Changing boreal methane sources and constant biomass burning during the last termination

Author: Fischer, Hubertus, Behrens, Melanie, Bock, Michael, Richter, Ulrike Christina, Schmitt, Jochen, Loulergue, L., Chappellaz, J., Spahni, R., Blunier, T., Leuenberger, M., Stocker, T. F., Fischer, Hubertus, Behrens, Melanie, Bock, Michael, Richter, Ulrike Christina, Schmitt, Jochen, Loulergue, L., Chappellaz, J., Spahni, R., Blunier, T., Leuenberger, M., and Stocker, T. F.
Published: 2008

17. The EDC3 chronology for the EPICA Dome C ice core

Author: Parrenin, F., Barnola, J. M., Beer, J., Blunier, T., Castellano, E., Chappellaz, J., Dreyfus, G., Fischer, Hubertus, Fujita, S., Jouzel, J., Kawamura, K., Lemieux-Dudon, B., Loulergue, L., Masson-Delmotte, V., Narcisi, B., Petit, J., Raisbeck, G., Raynaud, D., Ruth, Urs, Schwander, J., Severi, M., Spahni, R., Steffensen, J. P., Svensson, A., Udisti, R., Waelbroeck, C., Wolff, E., Parrenin, F., Barnola, J. M., Beer, J., Blunier, T., Castellano, E., Chappellaz, J., Dreyfus, G., Fischer, Hubertus, Fujita, S., Jouzel, J., Kawamura, K., Lemieux-Dudon, B., Loulergue, L., Masson-Delmotte, V., Narcisi, B., Petit, J., Raisbeck, G., Raynaud, D., Ruth, Urs, Schwander, J., Severi, M., Spahni, R., Steffensen, J. P., Svensson, A., Udisti, R., Waelbroeck, C., and Wolff, E.
Published: 2007

18. Orbital and millennial Antarctic climate variability over the past 800 000 years

Author: Jouzel, J., Masson-Delmotte, V., Cattani, O., Dreyfus, G., Falourd, S., Hoffmann, G., Minster, B., Nouet, J., Barnola, J. M., Chappellaz, J., Fischer, Hubertus, Gallet, J. C., Johnsen, S., Leuenberger, M., Loulergue, L., Luethi, D., Oerter, Hans, Parrenin, F., Raisbeck, G., Raynaud, D., Schwander, J., Spahni, R., Souchez, R., Selmo, E., Schilt, A., Steffensen, J. P., Stenni, B., Stauffer, B., Stocker, T. F., Tison, J. L., Werner, Martin, Wolff, E. W., Jouzel, J., Masson-Delmotte, V., Cattani, O., Dreyfus, G., Falourd, S., Hoffmann, G., Minster, B., Nouet, J., Barnola, J. M., Chappellaz, J., Fischer, Hubertus, Gallet, J. C., Johnsen, S., Leuenberger, M., Loulergue, L., Luethi, D., Oerter, Hans, Parrenin, F., Raisbeck, G., Raynaud, D., Schwander, J., Spahni, R., Souchez, R., Selmo, E., Schilt, A., Steffensen, J. P., Stenni, B., Stauffer, B., Stocker, T. F., Tison, J. L., Werner, Martin, and Wolff, E. W.
Published: 2007

19. The EDC3 chronology for the EPICA Dome C ice core

Author: Parrenin, Frederic, Barnola, J.-M., Beer, J., Blunier, Thomas, Castellano, E., Chappellaz, J., Dreyfus, G., Fischer, Hubertus, Fujita, S., Jouzel, Jean, Kawamura, K., Lemieux, B., Loulergue, L., Masson-Delmotte, Valerie, Narcisi, B., Petit, J.-R., Raisbeck, Grant, Raynaud, D., Ruth, Urs, Schwander, J., Severi, M., Spahni, R., Steffensen, Jørgen Peder, Svensson, Anders, Udisti, R., Waelbroeck, C., Wolff, Eric, Parrenin, Frederic, Barnola, J.-M., Beer, J., Blunier, Thomas, Castellano, E., Chappellaz, J., Dreyfus, G., Fischer, Hubertus, Fujita, S., Jouzel, Jean, Kawamura, K., Lemieux, B., Loulergue, L., Masson-Delmotte, Valerie, Narcisi, B., Petit, J.-R., Raisbeck, Grant, Raynaud, D., Ruth, Urs, Schwander, J., Severi, M., Spahni, R., Steffensen, Jørgen Peder, Svensson, Anders, Udisti, R., Waelbroeck, C., and Wolff, Eric
Abstract: Udgivelsesdato: 17 August
Published: 2007

20. New constraints on the gas age-ice age difference along EPICA ice cores, 0-50 kyr

Author: Loulergue, L., Parrenin, F., Blunier, Thomas, Barnola, J. M., Spahni, R., Schilt, A., Raisbeck, G., Chappellaz, J., Loulergue, L., Parrenin, F., Blunier, Thomas, Barnola, J. M., Spahni, R., Schilt, A., Raisbeck, G., and Chappellaz, J.
Published: 2007

21. Synchronization of ice core records via atmospheric gases

Author: Blunier, Thomas, Spahni, R., Barnola, J. M., Loulergue, L., Schwander, J., Blunier, Thomas, Spahni, R., Barnola, J. M., Loulergue, L., and Schwander, J.
Published: 2007

22. One-to-one coupling of glacial climate variability in Greenland and Antarctica

Author: EPICA Community Members, The, Barbante, C., Barnola, J.-M., Becagli, S., Beer, J., Bigler, M., Boutron, C., Blunier, T., Castellano, E., Cattani, O., Chappellaz, J., Dahl-Jensen, D., Debret, M., Delmonte, B., Dick, Dorothee, Falourd, S., Faria, S., Federer, U., Fischer, Hubertus, Freitag, Johannes, Frenzel, Andreas, Fritzsche, Diedrich, Fundel, Felix, Gabrielli, P., Gaspari, V., Gersonde, Rainer, Graf, W., Grigoriev, D., Hamann, Ilka, Hansson, M., Hoffmann, G., Hutterli, M. A., Huybrechts, Philippe, Isaksson, E., Johnsen, S., Jouzel, J., Kaczmarska, M., Karlin, T., Kaufmann, P., Kipfstuhl, Sepp, Kohno, Mika, Lambert, F., Lambrecht, Anja, Lambrecht, Astrid, Landais, A., Lawer, G., Leuenberger, M., Littot, G., Loulergue, L., Lüthi, D., Maggi, V., Marino, F., Masson-Delmotte, V., Meyer, Hanno, Miller, Heinrich, Mulvaney, R., Narcisi, B., Oerlemans, J., Oerter, Hans, Parrenin, F., Petit, J.-R., Raisbeck, G., Raynaud, D., Röthlisberger, R., Ruth, Urs, Rybak, Oleg, Severi, M., Schmitt, Jochen, Schwander, J., Siegenthaler, U., Siggaard-Andersen, M.-L., Spahni, R., Steffensen, J. P., Stenni, B., Stocker, T. F., Tison, J.-L., Traversi, R., Udisti, R., Valero-Delgado, Fernando, van den Broeke, M. R., van de Wal, R. S. W., Wagenbach, D., Wegner, Anna, Weiler, K., Wilhelms, Frank, Winther, J.-G., Wolff, E., EPICA Community Members, The, Barbante, C., Barnola, J.-M., Becagli, S., Beer, J., Bigler, M., Boutron, C., Blunier, T., Castellano, E., Cattani, O., Chappellaz, J., Dahl-Jensen, D., Debret, M., Delmonte, B., Dick, Dorothee, Falourd, S., Faria, S., Federer, U., Fischer, Hubertus, Freitag, Johannes, Frenzel, Andreas, Fritzsche, Diedrich, Fundel, Felix, Gabrielli, P., Gaspari, V., Gersonde, Rainer, Graf, W., Grigoriev, D., Hamann, Ilka, Hansson, M., Hoffmann, G., Hutterli, M. A., Huybrechts, Philippe, Isaksson, E., Johnsen, S., Jouzel, J., Kaczmarska, M., Karlin, T., Kaufmann, P., Kipfstuhl, Sepp, Kohno, Mika, Lambert, F., Lambrecht, Anja, Lambrecht, Astrid, Landais, A., Lawer, G., Leuenberger, M., Littot, G., Loulergue, L., Lüthi, D., Maggi, V., Marino, F., Masson-Delmotte, V., Meyer, Hanno, Miller, Heinrich, Mulvaney, R., Narcisi, B., Oerlemans, J., Oerter, Hans, Parrenin, F., Petit, J.-R., Raisbeck, G., Raynaud, D., Röthlisberger, R., Ruth, Urs, Rybak, Oleg, Severi, M., Schmitt, Jochen, Schwander, J., Siegenthaler, U., Siggaard-Andersen, M.-L., Spahni, R., Steffensen, J. P., Stenni, B., Stocker, T. F., Tison, J.-L., Traversi, R., Udisti, R., Valero-Delgado, Fernando, van den Broeke, M. R., van de Wal, R. S. W., Wagenbach, D., Wegner, Anna, Weiler, K., Wilhelms, Frank, Winther, J.-G., and Wolff, E.
Abstract: Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth’s climate dynamics. For the last glacial period, ice core stud- ies1,2 have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard–Oeschger events in Greenland3–5 through the Atlantic meridional over- turning circulation6–8. It has been unclear, however, whether the shorter Dansgaard–Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland9, the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard–Oeschger events by the bipolar seesaw6. The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.
Published: 2006

23. One-to-one coupling of glacial climate variability in Greenland and Antarctica

Author: Barbante, C, Barnola, J, Becagli, S, Beer, J, Bigler, M, Boutron, C, Blunier, T, Castellano, E, Cattani, O, Chappellaz, J, Dahl Jensen, D, Debret, M, Delmonte, B, Dick, D, Falourd, S, Faria, S, Federer, U, Fischer, H, Freitag, J, Frenzel, A, Fritzsche, D, Fundel, F, Gabrielli, P, Gaspari, V, Gersonde, R, Graf, W, Grigoriev, D, Hamann, I, Hansson, M, Hoffmann, G, Hutterli, M, Huybrechts, P, Isaksson, E, Johnsen, S, Jouzel, J, Kaczmarska, M, Karlin, T, Kaufmann, P, Kipfstuhl, S, Kohno, M, Lambert, F, Lambrecht, A, Landais, A, Lawer, G, Leuenberger, M, Littot, G, Loulergue, L, Luthi, D, Maggi, V, Marino, F, Masson Delmotte, V, Meyer, H, Miller, H, Mulvaney, R, Narcisi, B, Oerlemans, J, Oerter, H, Parrenin, F, Petit, J, Raisbeck, G, Raynaud, D, Rothlisberger, R, Ruth, U, Rybak, O, Severi, M, Schmitt, J, Schwander, J, Siegenthaler, U, Siggaard Andersen, M, Spahni, R, Steffensen, J, Stenni, B, Stocker, T, Tison, J, Traversi, R, Udisti, R, Valero Delgado, F, van den Broeke, M, van de Wal, R, Wagenbach, D, Wegner, A, Weiler, K, Wilhelms, F, Winther, J, Wolff, E, Barnola, JM, DELMONTE, BARBARA, Hutterli, MA, Petit, JR, Siggaard Andersen, ML, Steffensen, JP, Stocker, TF, Tison, JL, van den Broeke, MR, van de Wal, RSW, Winther, JG, Wolff, E., MAGGI, VALTER, Barbante, C, Barnola, J, Becagli, S, Beer, J, Bigler, M, Boutron, C, Blunier, T, Castellano, E, Cattani, O, Chappellaz, J, Dahl Jensen, D, Debret, M, Delmonte, B, Dick, D, Falourd, S, Faria, S, Federer, U, Fischer, H, Freitag, J, Frenzel, A, Fritzsche, D, Fundel, F, Gabrielli, P, Gaspari, V, Gersonde, R, Graf, W, Grigoriev, D, Hamann, I, Hansson, M, Hoffmann, G, Hutterli, M, Huybrechts, P, Isaksson, E, Johnsen, S, Jouzel, J, Kaczmarska, M, Karlin, T, Kaufmann, P, Kipfstuhl, S, Kohno, M, Lambert, F, Lambrecht, A, Landais, A, Lawer, G, Leuenberger, M, Littot, G, Loulergue, L, Luthi, D, Maggi, V, Marino, F, Masson Delmotte, V, Meyer, H, Miller, H, Mulvaney, R, Narcisi, B, Oerlemans, J, Oerter, H, Parrenin, F, Petit, J, Raisbeck, G, Raynaud, D, Rothlisberger, R, Ruth, U, Rybak, O, Severi, M, Schmitt, J, Schwander, J, Siegenthaler, U, Siggaard Andersen, M, Spahni, R, Steffensen, J, Stenni, B, Stocker, T, Tison, J, Traversi, R, Udisti, R, Valero Delgado, F, van den Broeke, M, van de Wal, R, Wagenbach, D, Wegner, A, Weiler, K, Wilhelms, F, Winther, J, Wolff, E, Barnola, JM, DELMONTE, BARBARA, Hutterli, MA, Petit, JR, Siggaard Andersen, ML, Steffensen, JP, Stocker, TF, Tison, JL, van den Broeke, MR, van de Wal, RSW, Winther, JG, Wolff, E., and MAGGI, VALTER
Abstract: Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies(1,2) have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard - Oeschger events in Greenland(3-5) through the Atlantic meridional overturning circulation(6-8). It has been unclear, however, whether the shorter Dansgaard - Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland(9), the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard - Oeschger events by the bipolar seesaw(6). The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.
Published: 2006

24. Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period

Author: Capron, E., primary, Landais, A., additional, Chappellaz, J., additional, Schilt, A., additional, Buiron, D., additional, Dahl-Jensen, D., additional, Johnsen, S. J., additional, Jouzel, J., additional, Lemieux-Dudon, B., additional, Loulergue, L., additional, Leuenberger, M., additional, Masson-Delmotte, V., additional, Meyer, H., additional, Oerter, H., additional, and Stenni, B., additional
Published: 2010
Full Text: View/download PDF

25. Synchronising EDML and NorthGRIP ice cores using δ18O of atmospheric oxygen (δ18Oatm) and CH4 measurements over MIS5 (80–123 kyr)

Author: Capron, E., primary, Landais, A., additional, Lemieux-Dudon, B., additional, Schilt, A., additional, Masson-Delmotte, V., additional, Buiron, D., additional, Chappellaz, J., additional, Dahl-Jensen, D., additional, Johnsen, S., additional, Leuenberger, M., additional, Loulergue, L., additional, and Oerter, H., additional
Published: 2010
Full Text: View/download PDF

26. Natural variations of methane and nitrous oxide from ice cores

Author: Blunter, Thomas, primary, Schilt, A, additional, Loulergue, L, additional, Barnola, J-M, additional, Bock, M, additional, Chappellaz, J, additional, Fischer, H, additional, Lemieux, B, additional, Masson-Delmotte, V, additional, Raynaud, D, additional, Spahni, R, additional, and Stocker, T F, additional
Published: 2009
Full Text: View/download PDF

27. New constraints on the gas age-ice age difference along the EPICA ice cores, 0–50 kyr

Author: Loulergue, L., primary, Parrenin, F., additional, Blunier, T., additional, Barnola, J.-M., additional, Spahni, R., additional, Schilt, A., additional, Raisbeck, G., additional, and Chappellaz, J., additional
Published: 2007
Full Text: View/download PDF

28. The EDC3 chronology for the EPICA Dome C ice core

Author: Parrenin, F., primary, Barnola, J.-M., additional, Beer, J., additional, Blunier, T., additional, Castellano, E., additional, Chappellaz, J., additional, Dreyfus, G., additional, Fischer, H., additional, Fujita, S., additional, Jouzel, J., additional, Kawamura, K., additional, Lemieux-Dudon, B., additional, Loulergue, L., additional, Masson-Delmotte, V., additional, Narcisi, B., additional, Petit, J.-R., additional, Raisbeck, G., additional, Raynaud, D., additional, Ruth, U., additional, Schwander, J., additional, Severi, M., additional, Spahni, R., additional, Steffensen, J. P., additional, Svensson, A., additional, Udisti, R., additional, Waelbroeck, C., additional, and Wolff, E., additional
Published: 2007
Full Text: View/download PDF

29. Synchronization of ice core records via atmospheric gases

Author: Blunier, T., primary, Spahni, R., additional, Barnola, J.-M., additional, Chappellaz, J., additional, Loulergue, L., additional, and Schwander, J., additional
Published: 2007
Full Text: View/download PDF

30. Supplementary material to "The EDC3 chronology for the EPICA Dome C ice core"

Author: Parrenin, F., primary, Barnola, J.-M., additional, Beer, J., additional, Blunier, T., additional, Castellano, E., additional, Chappellaz, J., additional, Dreyfus, G., additional, Fischer, H., additional, Fujita, S., additional, Jouzel, J., additional, Kawamura, K., additional, Lemieux-Dudon, B., additional, Loulergue, L., additional, Masson-Delmotte, V., additional, Narcisi, B., additional, Petit, J.-R., additional, Raisbeck, G., additional, Raynaud, D., additional, Ruth, U., additional, Schwander, J., additional, Severi, M., additional, Spahni, R., additional, Steffensen, J. P., additional, Svensson, A., additional, Udisti, R., additional, Waelbroeck, C., additional, and Wolff, E., additional
Published: 2007
Full Text: View/download PDF

31. Supplementary material to "New constraints on the gas age-ice age difference along the EPICA ice cores, 0–50 kyr"

Author: Loulergue, L., primary, Parrenin, F., additional, Blunier, T., additional, Barnola, J.-M., additional, Spahni, R., additional, Schilt, A., additional, Raisbeck, G., additional, and Chappellaz, J., additional
Published: 2007
Full Text: View/download PDF

32. Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core

Author: Loulergue, L., Schilt, A., Landais, A., Samyn, D., Tison, J.-L., Delmonte, B., Lipenkov, V., Johnsen, S., Pol, K., Durand, G., De Angelis, M., Littot, G., Stenni, B., Souchez, R., Wegner, A., Udisti, R., Dahl-Jensen, D., Fischer, H., Bigler, M., Dreyfus, G., Spahni, R., Masson-Delmotte, V., Jouzel, J., Wolff, E., Bereiter, B., Lorrain, R., Hansson, M., Barnola, J.-M., and Petit, J.-R.
Subjects: 13. Climate action, 530 Physics
Abstract: An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges in the near future, it is essential to judge how deep these records remain unaltered, since the proximity of the bedrock is likely to interfere both with the recorded temporal sequence and the ice properties. In this paper, we present a multiparametric study (δD-δ18Oice, δ18Oatm, total air content, CO2, CH4, N2O, dust, high-resolution chemistry, ice texture) of the bottom 60 m of the EPICA (European Project for Ice Coring in Antarctica) Dome C ice core from central Antarctica. These bottom layers were subdivided into two distinct facies: the lower 12 m showing visible solid inclusions (basal dispersed ice facies) and the upper 48 m, which we will refer to as the "basal clean ice facies". Some of the data are consistent with a pristine paleoclimatic signal, others show clear anomalies. It is demonstrated that neither large-scale bottom refreezing of subglacial water, nor mixing (be it internal or with a local basal end term from a previous/initial ice sheet configuration) can explain the observed bottom-ice properties. We focus on the high-resolution chemical profiles and on the available remote sensing data on the subglacial topography of the site to propose a mechanism by which relative stretching of the bottom-ice sheet layers is made possible, due to the progressively confining effect of subglacial valley sides. This stress field change, combined with bottom-ice temperature close to the pressure melting point, induces accelerated migration recrystallization, which results in spatial chemical sorting of the impurities, depending on their state (dissolved vs. solid) and if they are involved or not in salt formation. This chemical sorting effect is responsible for the progressive build-up of the visible solid aggregates that therefore mainly originate "from within", and not from incorporation processes of debris from the ice sheet's substrate. We further discuss how the proposed mechanism is compatible with the other ice properties described. We conclude that the paleoclimatic signal is only marginally affected in terms of global ice properties at the bottom of EPICA Dome C, but that the timescale was considerably distorted by mechanical stretching of MIS20 due to the increasing influence of the subglacial topography, a process that might have started well above the bottom ice. A clear paleoclimatic signal can therefore not be inferred from the deeper part of the EPICA Dome C ice core. Our work suggests that the existence of a flat monotonic ice–bedrock interface, extending for several times the ice thickness, would be a crucial factor in choosing a future "oldest ice" drilling location in Antarctica.

33. Orbital and millennial Antarctic climate variability over the past 800,000 years

Author: Jouzel, J., Masson-Delmotte, V., Cattani, O., Dreyfus, G., Falourd, S., Hoffmann, G., Minster, B., Nouet, J., Barnola, J.M., Chappellaz, J., Fischer, H., Gallet, J.C., Johnsen, S., Leuenberger, M., Loulergue, L., Luethi, D., Oerter, H., Parrenin, F., Raisbeck, G., Raynaud, D., Schilt, Adrian, Schwander, J., Selmo, E., Souchez, R., Spahni, R., Stauffer, B., Steffensen, J.P., Stenni, B., Stocker, T. F., Tison, J.L., Werner, M., and Wolff, E.W.
Subjects: 13. Climate action, 530 Physics
Abstract: A high-resolution deuterium profile is now available along the entire European Project for Ice Coring in Antarctica Dome C ice core, extending this climate record back to marine isotope stage 20.2, ��800,000 years ago. Experiments performed with an atmospheric general circulation model including water isotopes support its temperature interpretation. We assessed the general correspondence between Dansgaard-Oeschger events and their smoothed Antarctic counterparts for this Dome C record, which reveals the presence of such features with similar amplitudes during previous glacial periods. We suggest that the interplay between obliquity and precession accounts for the variable intensity of interglacial periods in ice core records.

34. Atmospheric science: Atmospheric methane and nitrous oxide of the late pleistocene from Antarctic Ice Cores

Author: Spahni, R., Chappellaz, J., Stocker, T. F., Loulergue, L., Hausammann, G., Kawamura, K., Fluckiger, J., Schwander, J., Raynaud, D., Masson-Delmotte, V., and Jouzel, J.
Subjects: atmospheric chemistry, Holocene values, Atmospheric chemistry, nitrous oxide, Holocene, Concentration (process), methane, article, artifact, methanogenesis, Pleistocene, Interglacials, climate change, priority journal, greenhouse gas, ice core record, atmosphere, Antarctica, Atmospheric methanes, Nitrous oxides, Glaciers, Methane, paleoatmosphere
Abstract: The European Project for Ice Coring in Antarctica Dome C ice core enables us to extend existing records of atmospheric methane (CH4) and nitrous oxide (N2O) back to 650,000 years before the present. A combined record of CH4 measured along the Dome C and the Vostok ice cores demonstrates, within the resolution of our measurements, that preindustrial concentrations over Antarctica have not exceeded 773 ± 15 ppbv (parts per billion by volume) during the past 650,000 years. Before 420,000 years ago, when interglacials were cooler, maximum CH4 concentrations were only about 600 ppbv, similar to lower Holocene values. In contrast, the N2O record shows maximum concentrations of 278 ± 7 ppbv, slightly higher than early Holocene values.

35. The EDC3 chronology for the EPICA Dome C ice core

Author: Parrenin, F., Barnola, J.-M., Beer, J., Blunier, T., Castellano, E., Chappellaz, J., Dreyfus, G., Fischer, H., Fujita, S., Jouzel, J., Kawamura, K., Lemieux-Dudon, B., Loulergue, L., Masson-Delmotte, V., Narcisi, B., Petit, J.-R., Raisbeck, G., Raynaud, D., Ruth, U., Schwander, J., Severi, M., Spahni, R., Steffensen, J. P., Svensson, A., Udisti, R., Waelbroeck, C., and Wolff, E.
Subjects: 13. Climate action, 530 Physics
Abstract: The EPICA (European Project for Ice Coring in Antarctica) Dome C drilling in East Antarctica has now been completed to a depth of 3260 m, at only a few meters above bedrock. Here we present the new EDC3 chronology, which is based on the use of 1) a snow accumulation and mechanical flow model, and 2) a set of independent age markers along the core. These are obtained by pattern matching of recorded parameters to either absolutely dated paleoclimatic records, or to insolation variations. We show that this new time scale is in excellent agreement with the Dome Fuji and Vostok ice core time scales back to 100 kyr within 1 kyr. Discrepancies larger than 3 kyr arise during MIS 5.4, 5.5 and 6, which points to anomalies in either snow accumulation or mechanical flow during these time periods. We estimate that EDC3 gives accurate event durations within 20% (2σ) back to MIS11 and accurate absolute ages with a maximum uncertainty of 6 kyr back to 800 kyr.

36. Interactive comment on "New constraints on the gas age-ice age difference along the EPICA ice cores, 0-50 kyr" by L. Loulergue et al.

Author: Loulergue, L.
Abstract: A review of the report "New Constraints on the Gas Age-Ice Age Difference Along the EPICA Ice Cores, 0-50 kyr," by L. Loulergue and colleagues is presented. Dissimilarities between the empirical and modelled delta depth are of the same amplitude as the one from the delta age, confirming an overestimation of the CODIE for all the glacial period as have already planned.
Published: 2007

37. One-to-one coupling of glacial climate variability in Greenland and Antarctica

Author: George R. Hoffmann, Silvia Becagli, Jean Jouzel, Oleg Rybak, Philippe Huybrechts, M. Kaczmarska, Astrid Lambrecht, Felix Fundel, L. Loulergue, K. Weiler, E. Castellano, Hutterli, Fernando Valero-Delgado, Mika Kohno, Fabrice Lambert, Roberto Udisti, Gunther Lawer, Elisabeth Isaksson, Hubertus Fischer, J. R. Petit, Valter Maggi, J. Beer, Heinrich Miller, Markus Leuenberger, Claude F. Boutron, M.-L. Siggaard-Andersen, Anna Wegner, Torbjörn Karlin, Thomas Blunier, Wolfgang Graf, Ilka Hamann, Patrik R Kaufmann, Margareta Hansson, Andreas Frenzel, J. M. Barnola, H. Oerter, Vania Gaspari, Urs Federer, Hanno Meyer, Sigfus J Johnsen, Robert Mulvaney, Biancamaria Narcisi, Jean-Louis Tison, Jørgen Peder Steffensen, Johannes Oerlemans, Mirko Severi, Eric W. Wolff, Grant M. Raisbeck, Olivier Cattani, U. Ruth, Diedrich Fritzsche, D. Grigoriev, Geneviève C Littot, Paolo Gabrielli, Rita Traversi, Dietmar Wagenbach, Urs Siegenthaler, Regine Röthlisberger, M. R. van den Broeke, D. Dick, Barbara Delmonte, Johannes Freitag, Frank Wilhelms, F. Marino, Jan-Gunnar Winther, Maxime Debret, Renato Spahni, S. Falourd, Jakob Schwander, Barbara Stenni, S. Kipfstuhl, Dieter Lüthi, Jérôme Chappellaz, Dominique Raynaud, Thomas F. Stocker, Dorthe Dahl-Jensen, M. Bigler, Frédéric Parrenin, Carlo Barbante, Rainer Gersonde, Valérie Masson-Delmotte, Amaelle Landais, R. S. W. van de Wal, Jochen Schmitt, Sérgio H. Faria, Institute for the Dynamics of Environmental Processes-CNR, Department of Environmental Sciences, University of Ca’ Foscari [Venice, Italy], Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, University of Florence (UNIFI), Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern]-Universität Bern [Bern], Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), University Milano-Bicocca, Department of Bentho-pelagic processes, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Forschungszentrum fur Umwelt und Gesundheit (GSF), Helmholtz-Zentrum München (HZM), University College of London [London] (UCL), Department of Physical Geography and Quaternary Geology, Stockholm University, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Departement Geografie, Vrije Universiteit [Brussels] (VUB), Norwegian Polar Institute, Italian National agency for new technologies, Energy and sustainable economic development [Frascati] (ENEA), Institute for Marine and Atmospheric Research [Utrecht] (IMAU), Utrecht University [Utrecht], Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Department of Geological, Environmental and Marine Sciences [Trieste], Università degli studi di Trieste, Département des Sciences de la Terre, Université Libre de Bruxelles [Bruxelles] (ULB), Institute of Environmental Physics [Heidelberg] (IUP), Universität Heidelberg [Heidelberg], Barbante, C., Barnola, J. M., Becagli, S., Beer, J., Bigler, M., Boutron, C., Blunier, T., Castellano, E., Cattani, O., Chappellaz, J., Dahl Jensen, D., Debret, M., Delmonte, B., Dick, D., Falourd, S., Faria, S., Federer, U., Fischer, H., Freitag, J., Frenzel, A., Fritzsche, D., Fundel, F., Gabrielli, P., Gaspari, V., Gersonde, R., Graf, W., Grigoriev, D., Hamann, I, Hansson, M., Hoffmann, G., Hutterli, M. A., Huybrechts, P., Isaksson, E., Johnsen, S., Jouzel, J., Kaczmarska, M., Karlin, T., Kaufmann, P., Kipfstuhl, S., Kohno, M., Lambert, F., Lambrecht, A., Landais, A., Lawer, G., Leuenberger, M., Littot, G., Loulergue, L., Lüthi, D., Maggi, V., Marino, F., Masson Delmotte, V., Meyer, H., Miller, H., Mulvaney, R., Narcisi, B., Oerlemans, J., Oerter, H., Parrenin, F., Petit, J. R., Raisbeck, G., Raynaud, D., Röthlisberger, R., Ruth, U., Rybak, O., Severi, M., Schmitt, J., Schwander, J., Siegenthaler, U., Siggaard Andersen, M. L., Spahni, R., Steffensen, J. P., Stenni, Barbara, Stocker, T. F., Tison, J. L., Traversi, R., Udisti, R., Valero Delgado, F., van den Broeke, M. R., van de Wal R. S., W, Wagenbach, D., Wegner, A., Weiler, K., Wilhelms, F., Winther, J. G., Wolff, E., Barbante, C, Barnola, J, Becagli, S, Beer, J, Bigler, M, Boutron, C, Blunier, T, Castellano, E, Cattani, O, Chappellaz, J, Dahl Jensen, D, Debret, M, Delmonte, B, Dick, D, Falourd, S, Faria, S, Federer, U, Fischer, H, Freitag, J, Frenzel, A, Fritzsche, D, Fundel, F, Gabrielli, P, Gaspari, V, Gersonde, R, Graf, W, Grigoriev, D, Hansson, M, Hoffmann, G, Hutterli, M, Huybrechts, P, Isaksson, E, Johnsen, S, Jouzel, J, Kaczmarska, M, Karlin, T, Kaufmann, P, Kipfstuhl, S, Kohno, M, Lambert, F, Lambrecht, A, Landais, A, Lawer, G, Leuenberger, M, Littot, G, Loulergue, L, Luthi, D, Maggi, V, Marino, F, Masson Delmotte, V, Meyer, H, Miller, H, Mulvaney, R, Narcisi, B, Oerlemans, J, Oerter, H, Parrenin, F, Petit, J, Raisbeck, G, Raynaud, D, Rothlisberger, R, Ruth, U, Rybak, O, Severi, M, Schmitt, J, Schwander, J, Siegenthaler, U, Siggaard Andersen, M, Spahni, R, Steffensen, J, Stenni, B, Stocker, T, Tison, J, Traversi, R, Udisti, R, Valero Delgado, F, van den Broeke, M, van de Wal, R, Wagenbach, D, Wegner, A, Weiler, K, Wilhelms, F, Winther, J, Wolff, E, Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Swiss Federal Insitute of Aquatic Science and Technology [Dübendorf] (EAWAG), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), Vrije Universiteit Brussel (VUB), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Université libre de Bruxelles (ULB), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze = University of Florence (UniFI), Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), Helmholtz Zentrum München = German Research Center for Environmental Health, Università degli studi di Trieste = University of Trieste, Universität Heidelberg [Heidelberg] = Heidelberg University, Niels Bohr Institute ( NBI ), Laboratoire de glaciologie et géophysique de l'environnement ( LGGE ), Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ), University of Florence, Swiss Federal Institute of Aquatic Science and Technology ( EAWAG ), Climate and Environmental Physics [Bern], University of Bern, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] ( LSCE ), Université de Versailles Saint-Quentin-en-Yvelines ( UVSQ ) -Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Centre National de la Recherche Scientifique ( CNRS ), Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research ( AWI ), Forschungszentrum fur Umwelt und Gesundheit ( GSF ), Helmholtz-Zentrum München ( HZM ), University College of London [London] ( UCL ), British Antarctic Survey ( BAS ), Natural Environment Research Council ( NERC ), Vrije Universiteit [Brussel] ( VUB ), Italian National agency for new technologies, Energy and sustainable economic development [Frascati] ( ENEA ), Institute for Marine and Atmospheric Research Utrecht ( IMAU ), Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse ( CSNSM ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Department of Geological Environmental and Marine Sciences [Trieste], University of Trieste, Université Libre de Bruxelles [Bruxelles] ( ULB ), and Institute of Environmental Physics [Heidelberg] ( IUP )
Subjects: Glacial climate, 010504 meteorology & atmospheric sciences, Meridional overturning circulation, Greenland, ice cores, Atlantic meridional overturning circulation, ice, 010502 geochemistry & geophysics, 01 natural sciences, Arctic, Ice core, Northern and Southern hemispheres, methane, Antarctica, EPICA, Dansgaard–Oeschger events, Dansgaard–Oeschger event, Ice core studies, Multidisciplinary, geography.geographical_feature_category, European Project for Ice Coring in Antarctica, article, Future sea level, Water waves, Oceanography, climate change, priority journal, Climate state, [ SDU.STU.GL ] Sciences of the Universe [physics]/Earth Sciences/Glaciology, temperature effect, Ice cap climate, glacial environment, oceanic circulation, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, isotope, climate, Northern and Southern hemisphere, 0105 earth and related environmental sciences, geography, Temperature measurement, Glacial geology, climate variation, Ice-sheet model, Oxygen, 13. Climate action, ice core record, Abrupt climate change, Environmental science, Ice sheet, ice core
Abstract: International audience; Precise knowledge of the phase relationship between climate changes in the two hemispheres is a key for understanding the Earth's climate dynamics. For the last glacial period, ice core studies1, 2 have revealed strong coupling of the largest millennial-scale warm events in Antarctica with the longest Dansgaard–Oeschger events in Greenland3, 4, 5 through the Atlantic meridional overturning circulation6, 7, 8. It has been unclear, however, whether the shorter Dansgaard–Oeschger events have counterparts in the shorter and less prominent Antarctic temperature variations, and whether these events are linked by the same mechanism. Here we present a glacial climate record derived from an ice core from Dronning Maud Land, Antarctica, which represents South Atlantic climate at a resolution comparable with the Greenland ice core records. After methane synchronization with an ice core from North Greenland9, the oxygen isotope record from the Dronning Maud Land ice core shows a one-to-one coupling between all Antarctic warm events and Greenland Dansgaard–Oeschger events by the bipolar seesaw6. The amplitude of the Antarctic warm events is found to be linearly dependent on the duration of the concurrent stadial in the North, suggesting that they all result from a similar reduction in the meridional overturning circulation.
Published: 2006

38. Synchronising EDML and NorthGRIP ice cores using δ18O of atmospheric oxygen (δ18Oatm) and CH4 measurements over MIS5 (80–123 kyr)

Author: Capron, E., Landais, A., Lemieux-Dudon, B., Schilt, A., Masson-Delmotte, V., Buiron, D., Chappellaz, J., Dahl-Jensen, D., Johnsen, S., Leuenberger, M., Loulergue, L., and Oerter, H.
Subjects: *ICE cores, *FLUCTUATIONS (Physics), *ANTARCTIC ice
Abstract: Abstract: Water isotope records from the EPICA Dronning Maud Land (EDML) and the NorthGRIP ice cores have revealed a one to one coupling between Antarctic Isotope Maxima (AIM) and Greenland Dansgaard-Oeschger (DO) events back to 50kyr. In order to explore if this north–south coupling is persistent over Marine Isotopic Stage 5 (MIS 5), a common timescale must first be constructed. Here, we present new records of δ18O of O2 (δ18Oatm) and methane (CH4) measured in the air trapped in ice from the EDML (68–147kyr) and NorthGRIP (70–123kyr) ice cores. We demonstrate that, through the period of interest, CH4 records alone are not sufficient to construct a common gas timescale between the two cores. Millennial-scale variations of δ18Oatm are evidenced over MIS 5 both on the Antarctic and Greenland ice cores and are coupled to CH4 profiles to synchronise the NorthGRIP and EDML records. They are shown to be a precious tool for ice core synchronisation. With this new dating strategy, we produce the first continuous and accurate sequence of the north–south climatic dynamics on a common ice timescale for the last glacial inception and the first DO events of MIS 5, reducing relative dating uncertainties to an accuracy of a few centuries at the onset of DO events 24 to 20. This EDML-NorthGRIP synchronisation provides new firm evidence that the bipolar seesaw is a pervasive pattern from the beginning of the glacial period. The relationship between Antarctic warming amplitudes and their concurrent Greenland stadial duration highlights the particularity of DO event 21 and its Antarctic counterpart. Our results suggest a smaller Southern Ocean warming rate for this long DO event compared to DO events of MIS 3. [Copyright &y& Elsevier]
Published: 2010
Full Text: View/download PDF

39. Millennial and sub-millennial scale climatic variations recorded in polar ice cores over the last glacial period

Author: Valérie Masson-Delmotte, Markus Leuenberger, Hans Oerter, Sigfus J Johnsen, L. Loulergue, Dorthe Dahl-Jensen, Jérôme A Chappellaz, Barbara Stenni, D. Buiron, Hanno Meyer, Bénédicte Lemieux-Dudon, Amaelle Landais, Emilie Capron, Jean Jouzel, Adrian Schilt, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), CLIPS, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Centre for Ice and Climate [Copenhagen], Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Department of Bentho-pelagic processes, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Dipartimento di Scienze Geologiche [Trieste], Università degli studi di Trieste = University of Trieste, European Project: 39423,FP6-SUSTDEV,EPICA-MIS, Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern]-Universität Bern [Bern], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU)-Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Università degli studi di Trieste, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Capron, E., Landais, A., Chappellaz, J., Schilt, A., Buiron, D., Dahl Jensen, D., Johnsen, S. J., Jouzel, J., Lemieux Dudon, B., Loulergue, L., Leuenberger, M., Masson Delmotte, V., Meyer, H., Oerter, H., and Stenni, Barbara
Subjects: nitrogen isotopes, 010504 meteorology & atmospheric sciences, Stratigraphy, Greenland, polar ice core, global warming, 01 natural sciences, Arctic, Ice core, Ice age, paleotemperature, Cryosphere, interstadial, lcsh:TD169-171.8, Glacial period, lcsh:Environmental sciences, lcsh:GE1-350, Global and Planetary Change, geography.geographical_feature_category, oxygen isotopes, Last Glacial, European Project for Ice Coring in Antarctica, polar ice cores, GRIP, Queen Maud Land, ice sheet, nitrogen isotope, Climatology, lcsh:TD172-193.5, sea level change, Geology, timescale, 010506 paleontology, lcsh:Environmental protection, paleotemperatures, lcsh:Environmental pollution, paleoclimate, oxygen isotope, millennial scale climatic variability, [SDU.STU.GM]Sciences of the Universe [physics]/Earth Sciences/Geomorphology, 0105 earth and related environmental sciences, geography, Dansgaard-Oeschger event, Paleontology, Dansgaard-Oeschger events, Antarctica, marine isotope stage, East Antarctica, Arctic ice pack, climate variation, Ice-sheet model, 13. Climate action, Ice sheet
Abstract: Since its discovery in Greenland ice cores, the millennial scale climatic variability of the last glacial period has been increasingly documented at all latitudes with studies focusing mainly on Marine Isotopic Stage 3 (MIS 3; 28–60 thousand of years before present, hereafter ka) and characterized by short Dansgaard-Oeschger (DO) events. Recent and new results obtained on the EPICA and NorthGRIP ice cores now precisely describe the rapid variations of Antarctic and Greenland temperature during MIS 5 (73.5–123 ka), a time period corresponding to relatively high sea level. The results display a succession of long DO events enabling us to highlight a sub-millennial scale climatic variability depicted by i) short-lived and abrupt warming events preceding some Greenland InterStadial (GIS) (precursor-type events) and ii) abrupt warming events at the end of some GIS (rebound-type events). The occurrence of these secondary events is suggested to be driven by the Northern Hemisphere summertime insolation at 65° N together with the internal forcing of ice sheets. Thanks to a recent NorthGRIP-EPICA Dronning Maud Land (EDML) common timescale over MIS 5, the bipolar sequence of climatic events can be established at millennial to sub-millennial timescale. This provides evidence that a linear relationship is not satisfactory in explaining the link between Antarctic warming amplitudes and the duration of their concurrent Greenland Stadial (GS) for the entire glacial period. The conceptual model for a thermal bipolar seesaw permits a reconstruction of the Antarctic response to the northern millennial and sub-millennial scale variability over MIS 5. However, we show that when ice sheets are extensive, Antarctica does not necessarily warm during the whole GS as the thermal bipolar seesaw model would predict.
Published: 2018

40. Retrieving the paleoclimatic signal from the deeper part of the EPICA Dome C ice core

Author: Margareta Hansson, Dorthe Dahl-Jensen, Amaelle Landais, Valérie Masson-Delmotte, G. Dreyfus, J. M. Barnola, Denis Samyn, Geoffroy Durand, Barbara Stenni, K. Pol, Adrian Schilt, Geneviève C Littot, M. de Angelis, Jean-Louis Tison, Eric W. Wolff, Roberto Udisti, Barbara Delmonte, L. Loulergue, Vladimir Ya. Lipenkov, Hubertus Fischer, Jean Jouzel, Sigfus J Johnsen, Renato Spahni, Jean-Robert Petit, Bernhard Bereiter, Anna Wegner, Reginald Lorrain, Matthias Bigler, Roland Souchez, Département des Sciences de la Terre et de l'Environnement, Université Libre de Bruxelles [Bruxelles] (ULB), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern]-Universität Bern [Bern], University of Stockolm, Chemistry Department, University of Florence (UNIFI), Department of Bentho-pelagic processes, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), University Ca' Foscari, University of Ca’ Foscari [Venice, Italy], Niels Bohr Institute [Copenhagen] (NBI), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Arctic and Antarctic Research Institute (AARI), Russian Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet), Dipartimento di Scienze dell'Ambiente e del Territorio (DISAT), Università degli studi di Milano [Milano], Oak Ridge Institute for Science and Education Climate Change Policy and Technology Fellow with the US Department of Energy Office of Policy and International Affairs, Nagaoka University of Technology, Wolff, Eric [0000-0002-5914-8531], Apollo - University of Cambridge Repository, Université libre de Bruxelles (ULB), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Dipartimento di Scienze Ambientali, Informatica e Statistica, Università degli Studi di Milano [Milano] (UNIMI), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Università degli Studi di Firenze = University of Florence (UniFI), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Università degli Studi di Milano = University of Milan (UNIMI), Tison, J, de Angelis, M, Littot, G, Wolff, E, Fischer, H, Hansson, M, Bigler, M, Udisti, R, Wegner, A, Jouzel, J, Stenni, B, Johnsen, S, Masson Delmotte, V, Landais, A, Lipenkov, V, Loulergue, L, Barnola, J, Petit, J, Delmonte, B, Dreyfus, G, Dahl Jensen, D, Durand, G, Bereiter, B, Schilt, A, Spahni, R, Pol, K, Lorrain, R, Souchez, R, and Samyn, D
Subjects: Water Science and Technology, Earth-Surface Processes, 010504 meteorology & atmospheric sciences, 530 Physics, SUBGLACIAL LAKE VOSTOK, PAST 800,000 YEARS, BASAL ICE, CENTRAL GREENLAND, EAST ANTARCTICA, CLIMATE VARIABILITY, MILLENNIAL-SCALE, ANOMALOUS DIFFUSION, DEBRIS ENTRAINMENT, GAS-COMPOSITION, DEBRIS ENTRAINMENT, sub-01, Ice stream, CENTRAL GREENLAND, 3705 Geology, Antarctic sea ice, 010502 geochemistry & geophysics, 01 natural sciences, Ice shelf, 000 YEARS, ice cores, Antarctica, Paleoclimate, BASAL ICE, Meteorology and Climatology, Ice core, CLIMATE VARIABILITY, Sea ice, Ice divide, Petrology, Geomorphology, lcsh:Environmental sciences, ANOMALOUS DIFFUSION, 0105 earth and related environmental sciences, lcsh:GE1-350, geography, SUBGLACIAL LAKE VOSTOK, geography.geographical_feature_category, EAST ANTARCTICA, Géologie et minéralogie, European Project for Ice Coring in Antarctica, lcsh:QE1-996.5, PAST 800, 37 Earth Sciences, MILLENNIAL-SCALE, 3709 Physical Geography and Environmental Geoscience, GAS-COMPOSITION, lcsh:Geology, Settore GEO/08 - Geochimica e Vulcanologia, 13. Climate action, [SDE]Environmental Sciences, théorie et applications [Econométrie et méthodes statistiques], Ice sheet, Geology
Abstract: An important share of paleoclimatic information is buried within the lowermost layers of deep ice cores. Because improving our records further back in time is one of the main challenges in the near future, it is essential to judge how deep these records remain unaltered, since the proximity of the bedrock is likely to interfere both with the recorded temporal sequence and the ice properties. In this paper, we present a multiparametric study (δD-δ18Oice, δ18Oatm, total air content, CO2, CH4, N2O, dust, high-resolution chemistry, ice texture) of the bottom 60 m of the EPICA (European Project for Ice Coring in Antarctica) Dome C ice core from central Antarctica. These bottom layers were subdivided into two distinct facies: the lower 12 m showing visible solid inclusions (basal dispersed ice facies) and the upper 48 m, which we will refer to as the "basal clean ice facies". Some of the data are consistent with a pristine paleoclimatic signal, others show clear anomalies. It is demonstrated that neither large-scale bottom refreezing of subglacial water, nor mixing (be it internal or with a local basal end term from a previous/initial ice sheet configuration) can explain the observed bottom-ice properties. We focus on the high-resolution chemical profiles and on the available remote sensing data on the subglacial topography of the site to propose a mechanism by which relative stretching of the bottom-ice sheet layers is made possible, due to the progressively confining effect of subglacial valley sides. This stress field change, combined with bottom-ice temperature close to the pressure melting point, induces accelerated migration recrystallization, which results in spatial chemical sorting of the impurities, depending on their state (dissolved vs. solid) and if they are involved or not in salt formation. This chemical sorting effect is responsible for the progressive build-up of the visible solid aggregates that therefore mainly originate "from within", and not from incorporation processes of debris from the ice sheet's substrate. We further discuss how the proposed mechanism is compatible with the other ice properties described. We conclude that the paleoclimatic signal is only marginally affected in terms of global ice properties at the bottom of EPICA Dome C, but that the timescale was considerably distorted by mechanical stretching of MIS20 due to the increasing influence of the subglacial topography, a process that might have started well above the bottom ice. A clear paleoclimatic signal can therefore not be inferred from the deeper part of the EPICA Dome C ice core. Our work suggests that the existence of a flat monotonic ice-bedrock interface, extending for several times the ice thickness, would be a crucial factor in choosing a future "oldest ice" drilling location in Antarctica., SCOPUS: ar.j, info:eu-repo/semantics/published
Published: 2015

41. Orbital and millennial Antarctic climate variability over the past 800,000 years

Author: Grant M. Raisbeck, Bénédicte Minster, Renato Spahni, J. C. Gallet, Jean-Marc Barnola, Jakob Schwander, Frédéric Parrenin, Valérie Masson-Delmotte, Enricomaria Selmo, Bernhard Stauffer, Jérôme Chappellaz, Dominique Raynaud, Thomas F. Stocker, Adrian Schilt, Barbara Stenni, Jean-Louis Tison, Jørgen Peder Steffensen, D. Luethi, Sigfus J Johnsen, Eric W. Wolff, Hans Oerter, Jean Jouzel, S. Falourd, O. Cattani, Hubertus Fischer, L. Loulergue, Martin Werner, Markus Leuenberger, Gabrielle Dreyfus, Julius Nouet, G. P. Hoffmann, Roland Souchez, Jouzel, J., Masson Delmotte, V., Cattani, O., Dreyfus, G., Falourd, S., Hoffmann, G., Minster, B., Nouet, J., Barnola, J. M., Chappellaz, J., Fisher, H., Gallet, J. C., Johnsen, S., Leuenberger, M., Loulergue, L., Luethi, D., Oerter, H., Parrenin, F., Raisbeck, G., Raynaud, D., Schilt, A., Schwander, J., Selmo, E., Souchez, R., Spahni, R., Stauffer, B., Steffensen, J. P., Stenni, Barbara, Stocker, T. F., Tison, J. L., Werner, M., Wolff, E. W., Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), Abteilung Klinische Sozialmedizin, Berufs- und Umweltdermatologie, Universität Heidelberg [Heidelberg], Geophysics and Water Resources, Section for Geology [Copenhagen], Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU)-Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU)-Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Science Institute, University of Iceland [Reykjavik], Physics Institute, University of Bern, Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (CSNSM), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze della Terra [Parma], Università degli studi di Parma [Parme, Italie], Département des Sciences de la Terre et de l'Environnement, Université Libre de Bruxelles [Bruxelles] (ULB), Department of Geological, Environmental and Marine Sciences [Trieste], Università degli studi di Trieste, Max Planck Institute for Biogeochemistry (MPI-BGC), Max-Planck-Gesellschaft, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Universität Heidelberg [Heidelberg] = Heidelberg University, University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Università degli studi di Parma = University of Parma (UNIPR), Université libre de Bruxelles (ULB), Università degli studi di Trieste = University of Trieste, European Project: 39423,FP6-SUSTDEV,EPICA-MIS, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and University of Parma = Università degli studi di Parma [Parme, Italie]
Subjects: Marine isotope stage, marine environment, 010504 meteorology & atmospheric sciences, EPICA Dome C, Antarctica, deuterium profile, site temperature, millennial climate variability, glacial-interglacial cycles, 010502 geochemistry & geophysics, 01 natural sciences, Ice core, Dome Concordia, Cryosphere, isotope labeling, deuterium, Multidisciplinary, geography.geographical_feature_category, methane, European Project for Ice Coring in Antarctica, article, interglacial, Europe, climate change, Oceanography, priority journal, greenhouse gas, Climatology, Interglacial, temperature measurement, Geology, nitrogen oxide, general circulation model, Paleoclimatology, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, isotope, 0105 earth and related environmental sciences, geography, amplitude modulation, carbon dioxide, marine isotope stage, East Antarctica, proxy climate record, climate variation, Ice-sheet model, 13. Climate action, Settore GEO/08 - Geochimica e Vulcanologia, ice core record, atmosphere, Ice sheet, glacial mass balance, ice core
Abstract: A high-resolution deuterium profile is now available along the entire European Project for Ice Coring in Antarctica Dome C ice core, extending this climate record back to marine isotope stage 20.2, ~800,000 years ago. Experiments performed with an atmospheric general circulation model including water isotopes support its temperature interpretation. We assessed the general correspondence between Dansgaard-Oeschger events and their smoothed Antarctic counterparts for this Dome C record, which reveals the presence of such features with similar amplitudes during previous glacial periods. We suggest that the interplay between obliquity and precession accounts for the variable intensity of interglacial periods in ice core records. Northern and Southern hemisphere, methane, ice cores, Greenland, Antarctica, EPICA, Dansgaard–Oeschger events, Atlantic meridional overturning circulation.
Published: 2007

42. Orbital and millennial-scale features of atmospheric CH4 over the past 800,000 years.

Author: Loulergue L, Schilt A, Spahni R, Masson-Delmotte V, Blunier T, Lemieux B, Barnola JM, Raynaud D, Stocker TF, and Chappellaz J
Subjects: Greenhouse Effect, History, Ancient, Ice Cover, Temperature, Time Factors, Tropical Climate, Wetlands, Atmosphere chemistry, Methane analysis
Abstract: Atmospheric methane is an important greenhouse gas and a sensitive indicator of climate change and millennial-scale temperature variability. Its concentrations over the past 650,000 years have varied between approximately 350 and approximately 800 parts per 10(9) by volume (p.p.b.v.) during glacial and interglacial periods, respectively. In comparison, present-day methane levels of approximately 1,770 p.p.b.v. have been reported. Insights into the external forcing factors and internal feedbacks controlling atmospheric methane are essential for predicting the methane budget in a warmer world. Here we present a detailed atmospheric methane record from the EPICA Dome C ice core that extends the history of this greenhouse gas to 800,000 yr before present. The average time resolution of the new data is approximately 380 yr and permits the identification of orbital and millennial-scale features. Spectral analyses indicate that the long-term variability in atmospheric methane levels is dominated by approximately 100,000 yr glacial-interglacial cycles up to approximately 400,000 yr ago with an increasing contribution of the precessional component during the four more recent climatic cycles. We suggest that changes in the strength of tropical methane sources and sinks (wetlands, atmospheric oxidation), possibly influenced by changes in monsoon systems and the position of the intertropical convergence zone, controlled the atmospheric methane budget, with an additional source input during major terminations as the retreat of the northern ice sheet allowed higher methane emissions from extending periglacial wetlands. Millennial-scale changes in methane levels identified in our record as being associated with Antarctic isotope maxima events are indicative of ubiquitous millennial-scale temperature variability during the past eight glacial cycles.
Published: 2008
Full Text: View/download PDF

43. Changing boreal methane sources and constant biomass burning during the last termination.

Author: Fischer H, Behrens M, Bock M, Richter U, Schmitt J, Loulergue L, Chappellaz J, Spahni R, Blunier T, Leuenberger M, and Stocker TF
Subjects: Atmosphere chemistry, Carbon analysis, Carbon Isotopes, Cold Climate, Greenland, History, Ancient, Hydrogen analysis, Methane metabolism, Monte Carlo Method, Wetlands, Biomass, Fires statistics & numerical data, Ice Cover, Methane analysis, Methane chemistry, Temperature, Trees metabolism
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.
Published: 2008
Full Text: View/download PDF

44. Atmospheric methane and nitrous oxide of the Late Pleistocene from Antarctic ice cores.

Author: Spahni R, Chappellaz J, Stocker TF, Loulergue L, Hausammann G, Kawamura K, Flückiger J, Schwander J, Raynaud D, Masson-Delmotte V, and Jouzel J
Abstract: The European Project for Ice Coring in Antarctica Dome C ice core enables us to extend existing records of atmospheric methane (CH4) and nitrous oxide (N2O) back to 650,000 years before the present. A combined record of CH4 measured along the Dome C and the Vostok ice cores demonstrates, within the resolution of our measurements, that preindustrial concentrations over Antarctica have not exceeded 773 +/- 15 ppbv (parts per billion by volume) during the past 650,000 years. Before 420,000 years ago, when interglacials were cooler, maximum CH4 concentrations were only about 600 ppbv, similar to lower Holocene values. In contrast, the N2O record shows maximum concentrations of 278 +/- 7 ppbv, slightly higher than early Holocene values.
Published: 2005
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Region

Database

Publisher

44 results on '"Loulergue L"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources