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1. Bioavailability and Bioaccumulation of Pyrethroid Insecticides in Wildlife and Humans

Author

Aznar-Alemany, Ò., Eljarrat, E., Barceló, Damià, Series Editor, de Boer, Jacob, Editorial Board Member, Kostianoy, Andrey G., Series Editor, Garrigues, Philippe, Editorial Board Member, Hutzinger, Otto, Founding Editor, Gu, Ji-Dong, Editorial Board Member, Jones, Kevin C., Editorial Board Member, Knepper, Thomas P., Editorial Board Member, Negm, Abdelazim M., Editorial Board Member, Newton, Alice, Editorial Board Member, Nghiem, Duc Long, Editorial Board Member, Garcia-Segura, Sergi, Editorial Board Member, and Eljarrat, Ethel, editor

Published
2020
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2. Introduction to Pyrethroid Insecticides: Chemical Structures, Properties, Mode of Action and Use

Author

Aznar-Alemany, Ò., Eljarrat, E., Barceló, Damià, Series Editor, de Boer, Jacob, Editorial Board Member, Kostianoy, Andrey G., Series Editor, Garrigues, Philippe, Editorial Board Member, Hutzinger, Otto, Founding Editor, Gu, Ji-Dong, Editorial Board Member, Jones, Kevin C., Editorial Board Member, Knepper, Thomas P., Editorial Board Member, Negm, Abdelazim M., Editorial Board Member, Newton, Alice, Editorial Board Member, Nghiem, Duc Long, Editorial Board Member, Garcia-Segura, Sergi, Editorial Board Member, and Eljarrat, Ethel, editor

Published
2020
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3. Where to find 1.5 million yr old ice for the IPICS "Oldest-Ice" ice core

Author

Fischer, H, Severinghaus, J, Brook, E, Wolff, E, Albert, M, Alemany, O, Arthern, R, Bentley, C, Blankenship, D, Chappellaz, J, Creyts, T, Dahl-Jensen, D, Dinn, M, Frezzotti, M, Fujita, S, Gallee, H, Hindmarsh, R, Hudspeth, D, Jugie, G, Kawamura, K, Lipenkov, V, Miller, H, Mulvaney, R, Parrenin, F, Pattyn, F, Ritz, C, Schwander, J, Steinhage, D, van Ommen, T, and Wilhelms, F

Subjects
Climate Action, Physical Geography and Environmental Geoscience, Paleontology
Abstract

The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this progression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet. We can show that such old ice is most likely to exist in the plateau area of the East Antarctic ice sheet (EAIS) without stratigraphic disturbance and should be able to be recovered after careful presite selection studies. Based on a simple ice and heat flow model and glaciological observations, we conclude that positions in the vicinity of major domes and saddle position on the East Antarctic Plateau will most likely have such old ice in store and represent the best study areas for dedicated reconnaissance studies in the near future. In contrast to previous ice core drill site selections, however, we strongly suggest significantly reduced ice thickness to avoid bottom melting. For example for the geothermal heat flux and accumulation conditions at Dome C, an ice thickness lower than but close to about 2500 m would be required to find 1.5 Myr old ice (i.e., more than 700 m less than at the current EPICA Dome C drill site). Within this constraint, the resolution of an Oldest-Ice record and the distance of such old ice to the bedrock should be maximized to avoid ice flow disturbances, for example, by finding locations with minimum geothermal heat flux. As the geothermal heat flux is largely unknown for the EAIS, this parameter has to be carefully determined beforehand. In addition, detailed bedrock topography and ice flow history has to be reconstructed for candidates of an Oldest-Ice ice coring site. Finally, we argue strongly for rapid access drilling before any full, deep ice coring activity commences to bring datable samples to the surface and to allow an age check of the oldest ice.

Published
2013

5. The SUBGLACIOR drilling probe: hydraulic considerations

Author

Alemany, O., primary, Talalay, P., additional, Boissonneau, P., additional, Chappellaz, J., additional, Chemin, J. F., additional, Duphil, R., additional, Lefebvre, E., additional, Piard, L., additional, Possenti, P., additional, and Triest, J., additional

Published
2020
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6. The SUBGLACIOR drilling probe: hydraulic considerations.

Author

Alemany, O., Talalay, P., Boissonneau, P., Chappellaz, J., Chemin, J. F., Duphil, R., Lefebvre, E., Piard, L., Possenti, P., and Triest, J.

Subjects
*ICE cores, *DRILLING & boring, *MELTWATER, *MELTING, *ISOTOPES
Abstract

Using significant technological breakthroughs and unconventional approaches, the goal of the in situ probing of glacier ice for a better understanding of the orbital response of climate (SUBGLACIOR) project is to advance ice core research by inventing, constructing and testing an in situ probe to evaluate if a target site is suitable for recovering ice as old as 1.5 million years. Embedding a laser spectrometer, the probe is intended to make its own way down into the ice and to measure, in real time and down to the bedrock, the depth profiles of the ice dD water isotopes as well as the trapped CH4 gas concentration and dust concentration. The probe descent is achieved through electromechanical drilling combined with continuous meltwater sample production using a central melting finger in the drill head. A key aspect of the project lies in the design and implementation of an efficient method to continuously transfer to the surface the ice chips being produced by the drill head and from the refreezed water expulsed downstream from the melting finger, into the borehole. This paper presents a detailed calculation and analysis of the flow rates and pressure conditions required to overcome friction losses of the drilling fluid and to effectively transport ice chips to the surface. [ABSTRACT FROM AUTHOR]

Published
2021
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7. Where to find 1.5 million yr old ice for the IPICS 'Oldest-Ice' ice core

Author

Fischer, H., Severinghaus, J., Brook, E., Wolff, E., Albert, M., Alemany, O., Arthern, R., Bentley, C., Blankenship, D., Chappellaz, J., Creyts, T., Dahl-Jensen, D., Dinn, M., Frezzotti, M., Fujita, S., Gallee, H., Hindmarsh, R., Hudspeth, D., Jugie, G., Kawamura, K., Lipenkov, V., Miller, H., Mulvaney, R., Parrenin, Frédéric, Pattyn, F., Ritz, C., Schwander, J., Steinhage, D., Van Ommen, T., Wilhelms, F., Fischer, H., Severinghaus, J., Brook, E., Wolff, E., Albert, M., Alemany, O., Arthern, R., Bentley, C., Blankenship, D., Chappellaz, J., Creyts, T., Dahl-Jensen, D., Dinn, M., Frezzotti, M., Fujita, S., Gallee, H., Hindmarsh, R., Hudspeth, D., Jugie, G., Kawamura, K., Lipenkov, V., Miller, H., Mulvaney, R., Parrenin, F., Pattyn, F., Ritz, C., Schwander, J., Steinhage, D., Van Ommen, T., Wilhelms, F., Max Planck Institute for Solar System Research (MPS), Max-Planck-Gesellschaft, Scripps Institution of Oceanography (SIO), University of California [San Diego] (UC San Diego), University of California-University of California, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), Département de Physique Théorique, University of Geneva [Switzerland], CLIPS, 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)-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), Centre for Ice and Climate [Copenhagen], Niels Bohr Institute [Copenhagen] (NBI), 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), Italian National agency for new technologies, Energy and sustainable economic development [Frascati] (ENEA), National Institute of Polar Research [Tokyo] (NiPR), Physical Science Division, Natural Environment Research Council (NERC)-Natural Environment Research Council (NERC), Arctic and Antarctic Research Institute (AARI), Russian Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet), Institut des Géosciences de l’Environnement (IGE), Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Université Libre de Bruxelles [Bruxelles] (ULB), Physics Institute, University of Berne, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC), 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), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Université libre de Bruxelles (ULB), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Scripps Institution of Oceanography (SIO - UC San Diego), University of California (UC)-University of California (UC), Université de Genève = University of Geneva (UNIGE), 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), 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), Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), and Universität Bern [Bern] (UNIBE)

Subjects
Paléontologie et paléoécologie, Antarctic Plateau, sub-01, lcsh:Environmental protection, glaciation, heat flux, Stratigraphie, ice flow, Physical Geography and Environmental Geoscience, Quaternary, Environnement et pollution, lcsh:Environmental pollution, Dome Concordia, paleoclimate, lcsh:TD169-171.8, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, lcsh:Environmental sciences, ComputingMilieux_MISCELLANEOUS, lcsh:GE1-350, Paleontology, Calluna vulgaris, East Antarctica, cryosphere, Climate Action, greenhouse gas, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, geothermal energy, lcsh:TD172-193.5, Antarctica, bedrock, ice core, ice thickness
Abstract

The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this progression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet. We can show that such old ice is most likely to exist in the plateau area of the East Antarctic ice sheet (EAIS) without stratigraphic disturbance and should be able to be recovered after careful presite selection studies. Based on a simple ice and heat flow model and glaciological observations, we conclude that positions in the vicinity of major domes and saddle position on the East Antarctic Plateau will most likely have such old ice in store and represent the best study areas for dedicated reconnaissance studies in the near future. In contrast to previous ice core drill site selections, however, we strongly suggest significantly reduced ice thickness to avoid bottom melting. For example for the geothermal heat flux and accumulation conditions at Dome C, an ice thickness lower than but close to about 2500 m would be required to find 1.5 Myr old ice (i.e. more than 700 m less than at the current EPICA Dome C drill site). Within this constraint, the resolution of an Oldest-Ice record and the distance of such old ice to the bedrock should be maximized to avoid ice flow disturbances, for example, by finding locations with minimum geothermal heat flux. As the geothermal heat flux is largely unknown for the EAIS, this parameter has to be carefully determined beforehand. In addition, detailed bedrock topography and ice flow history has to be reconstructed for candidates of an Oldest-Ice ice coring site. Finally, we argue strongly for rapid access drilling before any full, deep ice coring activity commences to bring datable samples to the surface and to allow an age check of the oldest ice., SCOPUS: ar.j, info:eu-repo/semantics/published

Published
2013

9. Where to find 1.5 million yr old ice for the IPICS 'Oldest-Ice' ice core

Author

Fischer, Hubertus, Severinghaus, J., Brook, E., Wolff, E., Albert, M., Alemany, O., Arthern, R., Bentley, C., Blankenship, D., Chappellaz, J., Creyts, T., Dahl-Jensen, D., Dinn, M., Frezzotti, M., Fujita, S., Gallee, H., Hindmarsh, R., Hudspeth, D., Jugie, G., Kawamura, K., Lipenkov, V., Miller, H., Mulvaney, R., Pattyn, F., Ritz, C., Schwander, Jakob, Steinhage, D., van Ommen, T., and Wilhelms, F.

Subjects
530 Physics
Abstract

The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this progression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet. We can show that such old ice is most likely to exist in the plateau area of the East Antarctic ice sheet (EAIS) without stratigraphic disturbance and should be able to be recovered after careful pre-site selection studies. Based on a simple ice and heat flow model and glaciological observations, we conclude that positions in the vicinity of major domes and saddle position on the East Antarctic Plateau will most likely have such old ice in store and represent the best study areas for dedicated reconnaissance studies in the near future. In contrast to previous ice core drill site selections, however, we strongly suggest significantly reduced ice thickness to avoid bottom melting. For example for the geothermal heat flux and accumulation conditions at Dome C, an ice thickness lower than but close to about 2500 m would be required to find 1.5 Myr old ice (i.e., more than 700 m less than at the current EPICA Dome C drill site). Within this constraint, the resolution of an Oldest-Ice record and the distance of such old ice to the bedrock should be maximized to avoid ice flow disturbances, for example, by finding locations with minimum geothermal heat flux. As the geothermal heat flux is largely unknown for the EAIS, this parameter has to be carefully determined beforehand. In addition, detailed bedrock topography and ice flow history has to be reconstructed for candidates of an Oldest-Ice ice coring site. Finally, we argue strongly for rapid access drilling before any full, deep ice coring activity commences to bring datable samples to the surface and to allow an age check of the oldest ice.

Published
2013

12. The SUBGLACIOR drilling probe: concept and design

Author

Alemany, O., primary, Chappellaz, J., additional, Triest, J., additional, Calzas, M., additional, Cattani, O., additional, Chemin, J.F., additional, Desbois, Q., additional, Desbois, T., additional, Duphil, R., additional, Falourd, S., additional, Grilli, R., additional, Guillerme, C., additional, Kerstel, E., additional, Laurent, B., additional, Lefebvre, E., additional, Marrocco, N., additional, Pascual, O., additional, Piard, L., additional, Possenti, P., additional, Romanini, D., additional, Thiebaut, V., additional, and Yamani, R., additional

Published
2014
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13. Where to find 1.5 million yr old ice for the IPICS "Oldest-Ice" ice core

Author

Fischer, H., primary, Severinghaus, J., additional, Brook, E., additional, Wolff, E., additional, Albert, M., additional, Alemany, O., additional, Arthern, R., additional, Bentley, C., additional, Blankenship, D., additional, Chappellaz, J., additional, Creyts, T., additional, Dahl-Jensen, D., additional, Dinn, M., additional, Frezzotti, M., additional, Fujita, S., additional, Gallee, H., additional, Hindmarsh, R., additional, Hudspeth, D., additional, Jugie, G., additional, Kawamura, K., additional, Lipenkov, V., additional, Miller, H., additional, Mulvaney, R., additional, Parrenin, F., additional, Pattyn, F., additional, Ritz, C., additional, Schwander, J., additional, Steinhage, D., additional, van Ommen, T., additional, and Wilhelms, F., additional

Published
2013
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14. Where to find 1.5 million yr old ice for the IPICS "Oldest Ice" ice core

Author

Fischer, H., primary, Severinghaus, J., additional, Brook, E., additional, Wolff, E., additional, Albert, M., additional, Alemany, O., additional, Arthern, R., additional, Bentley, C., additional, Blankenship, D., additional, Chappellaz, J., additional, Creyts, T., additional, Dahl-Jensen, D., additional, Dinn, M., additional, Frezzotti, M., additional, Fujita, S., additional, Gallee, H., additional, Hindmarsh, R., additional, Hudspeth, D., additional, Jugie, G., additional, Kawamura, K., additional, Lipenkov, V., additional, Miller, H., additional, Mulvaney, R., additional, Pattyn, F., additional, Ritz, C., additional, Schwander, J., additional, Steinhage, D., additional, van Ommen, T., additional, and Wilhelms, F., additional

Published
2013
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15. The Hans Tausen drill: design, performance, further developments and some lessons learned

Author

Johnsen, S. J., Hansen, S. B., Sheldon, S. G., Dahl-Jensen, D., Steffensen, J. P., Augustin, L., Journé, P., Alemany, O., Rufli, H., Schwander, J., Azuma, N., Motoyama, H., Popp, T., Talalay, P., Thorsteinsson, T., Wilhelms, Frank, Zagorodnov, V., Johnsen, S. J., Hansen, S. B., Sheldon, S. G., Dahl-Jensen, D., Steffensen, J. P., Augustin, L., Journé, P., Alemany, O., Rufli, H., Schwander, J., Azuma, N., Motoyama, H., Popp, T., Talalay, P., Thorsteinsson, T., Wilhelms, Frank, and Zagorodnov, V.

Published
2007

16. The Hans Tausen drill:Design, performance, further developments and som lessons learned

Author

Johnsen, Sigfus Johann, Dahl-Jensen, Dorthe, Steffensen, Jørgen Peder, Popp, Trevor James, Hansen, Bo S., Sheldon, Simon, Journé, P., Laurent, A., Alemany, O., Rufli, H., Schwander, J., Azuma, N., Motoyama, H., Talalay, P., Thorsteinsson, T., Wilhelms, F., Zagorodnov, V., Johnsen, Sigfus Johann, Dahl-Jensen, Dorthe, Steffensen, Jørgen Peder, Popp, Trevor James, Hansen, Bo S., Sheldon, Simon, Journé, P., Laurent, A., Alemany, O., Rufli, H., Schwander, J., Azuma, N., Motoyama, H., Talalay, P., Thorsteinsson, T., Wilhelms, F., and Zagorodnov, V.

Abstract

In the mid-1990s, excellent results from the GRIP and GISP2 deep drilling projects in Greenland opened up funding for continued ice-coring efforts in Antarctica (EPICA) and Greenland (NorthGRIP). The Glaciology Group of the Niels Bohr Institute, University of Copenhagen, was assigned the task of providing drilling capability for these projects, as it had done for the GRIP project. The group decided to further simplify existing deep drill designs for better reliability and ease of handling. The drill design decided upon was successfully tested on Hans Tausen Ice Cap, Peary Land, Greenland, in 1995. The 5.0 m long Hans Tausen (HT) drill was a prototype for the ~11 m long EPICA and NorthGRIP versions of the drill which were mechanically identical to the HT drill except for a much longer core barrel and chips chamber. These drills could deliver up to 4 m long ice cores after some design improvements had been introduced. The Berkner Island (Antarctica) drill is also an extended HT drill capable of drilling 2 m long cores. The success of the mechanical design of the HT drill is manifested by over 12 km of good-quality ice cores drilled by the HT drill and its derivatives since 1995. Udgivelsesdato: december

Published
2007

18. Where to find 1.5 million yr old ice for the IPICS 'Oldest-Ice' ice core

Author

Pattyn, F., Jugie, G., Hudspeth, D., Chappellaz, J., Gallee, H., Kawamura, K., Lipenkov, V., Dinn, M., Dahl-Jensen, D., Severinghaus, J., Wolff, E., Brook, E., Arthern, R., Wilhelms, F., Fujita, S., Miller, H., Creyts, T., Alemany, O., Steinhage, D., Fischer, Hubertus, Albert, M., Frezzotti, M., Hindmarsh, R., Van Ommen, T., Ritz, C., Schwander, Jakob, Blankenship, D., Mulvaney, R., and Bentley, C.

Subjects
13. Climate action, 530 Physics
Abstract

The recovery of a 1.5 million yr long ice core from Antarctica represents a keystone of our understanding of Quaternary climate, the progression of glaciation over this time period and the role of greenhouse gas cycles in this progression. Here we tackle the question of where such ice may still be found in the Antarctic ice sheet. We can show that such old ice is most likely to exist in the plateau area of the East Antarctic ice sheet (EAIS) without stratigraphic disturbance and should be able to be recovered after careful pre-site selection studies. Based on a simple ice and heat flow model and glaciological observations, we conclude that positions in the vicinity of major domes and saddle position on the East Antarctic Plateau will most likely have such old ice in store and represent the best study areas for dedicated reconnaissance studies in the near future. In contrast to previous ice core drill site selections, however, we strongly suggest significantly reduced ice thickness to avoid bottom melting. For example for the geothermal heat flux and accumulation conditions at Dome C, an ice thickness lower than but close to about 2500 m would be required to find 1.5 Myr old ice (i.e., more than 700 m less than at the current EPICA Dome C drill site). Within this constraint, the resolution of an Oldest-Ice record and the distance of such old ice to the bedrock should be maximized to avoid ice flow disturbances, for example, by finding locations with minimum geothermal heat flux. As the geothermal heat flux is largely unknown for the EAIS, this parameter has to be carefully determined beforehand. In addition, detailed bedrock topography and ice flow history has to be reconstructed for candidates of an Oldest-Ice ice coring site. Finally, we argue strongly for rapid access drilling before any full, deep ice coring activity commences to bring datable samples to the surface and to allow an age check of the oldest ice.

19. Recent Antarctic Peninsula warming relative to Holocene climate and ice-shelf history.

Author

Mulvaney R, Abram NJ, Hindmarsh RC, Arrowsmith C, Fleet L, Triest J, Sime LC, Alemany O, and Foord S

Subjects
Antarctic Regions, Geography, Geologic Sediments chemistry, Global Warming history, History, 15th Century, History, 16th Century, History, 17th Century, History, 18th Century, History, 19th Century, History, 20th Century, History, 21st Century, History, Ancient, History, Medieval, Oceans and Seas, Seawater analysis, Temperature, Global Warming statistics & numerical data, Ice Cover
Abstract

Rapid warming over the past 50 years on the Antarctic Peninsula is associated with the collapse of a number of ice shelves and accelerating glacier mass loss. In contrast, warming has been comparatively modest over West Antarctica and significant changes have not been observed over most of East Antarctica, suggesting that the ice-core palaeoclimate records available from these areas may not be representative of the climate history of the Antarctic Peninsula. Here we show that the Antarctic Peninsula experienced an early-Holocene warm period followed by stable temperatures, from about 9,200 to 2,500 years ago, that were similar to modern-day levels. Our temperature estimates are based on an ice-core record of deuterium variations from James Ross Island, off the northeastern tip of the Antarctic Peninsula. We find that the late-Holocene development of ice shelves near James Ross Island was coincident with pronounced cooling from 2,500 to 600 years ago. This cooling was part of a millennial-scale climate excursion with opposing anomalies on the eastern and western sides of the Antarctic Peninsula. Although warming of the northeastern Antarctic Peninsula began around 600 years ago, the high rate of warming over the past century is unusual (but not unprecedented) in the context of natural climate variability over the past two millennia. The connection shown here between past temperature and ice-shelf stability suggests that warming for several centuries rendered ice shelves on the northeastern Antarctic Peninsula vulnerable to collapse. Continued warming to temperatures that now exceed the stable conditions of most of the Holocene epoch is likely to cause ice-shelf instability to encroach farther southward along the Antarctic Peninsula.

Published
2012
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20. [Analysis of cost minimization of epidural anesthesia compared with general anesthesia in oncologic coloproctologic surgery].

Author

Sabate A, Peña MJ, Vila C, and Alemany O

Subjects
Adolescent, Adult, Aged, Aged, 80 and over, Costs and Cost Analysis, Female, Humans, Male, Middle Aged, Anesthesia, Epidural economics, Anesthesia, General economics, Colorectal Neoplasms surgery
Abstract

Background: Combined general and epidural anaesthesia in abdominal surgery has shown, both, protective and no effect on final outcome. The aim of this study was to evaluate combined epidural and general anesthesia., Methods: One hundred and eighty four patients, diagnosed of neoplastic process, in whom an elective procedure of coloproctologic resection and reconstruction was scheduled during the period between January-1993 and December 1994, were studied. In thirty consecutive patients a combined general-epidural anaesthesia (EA) was performed. These patients were compared to thirty general anaesthesia patients (GA), selected randomly from the same period., Results: Both groups were comparable for demographic characteristics and for the type and duration of the surgical procedure. Red Blood Cells units transfused were 1.7 +/- 3 in the EA group and 1.4 +/- 1.9 in the GA group. After the operation, most of patients went to SICU. The length of the hospital stay was 13 +/- 6 days for GA group, while for EA group was .13 +/- 5. The hospital mortality for all operated patients (N = 184) was 1.1%, which were directly related to failure of surgical anastomosis. The need for mechanical ventilation and pulmonary complications were similar in both groups. When analyzing costs, EA group represented a value (pesetas) of 433,501 +/- 183,337 for GA group and 437,735 +/- 149,572 for EA group., Conclusions: As shown, in the actual context, we conclude that the anaesthetic technique did not have any influence on outcome or on cost.

Published
1997

21. [Influence of cardiac or respiratory pathology in the gasometric evolution during laparoscopic cholecystectomy].

Author

Vila C, Sabaté A, Biescas J, and Alemany O

Subjects
Aged, Female, Humans, Male, Middle Aged, Partial Pressure, Prospective Studies, Carbon Dioxide blood, Cholecystectomy, Laparoscopic, Heart Diseases blood, Oxygen blood, Respiration Disorders blood
Abstract

Objectives: To analyze the differences in gasometric behavior during laparoscopic cholecystectomy in patients with heart or respiratory disease., Patients and Methods: Prospective study of 19 ASA III patients grouped according to whether they suffered heart (group H, n = 10) or respiratory (group R, n = 9) disease. The patients were ventilated without reabsorption of CO2 and a flow volume of 12 ml/kg in order to achieve a positive end tidal pressure of CO2 (PetCO2) between 25 and 30 mmHg and no subsequent changes in ventilatory parameters. Arterial and venous gasometric values, PetCO2, hemodynamic data and airway pressure were analyzed at the following times: T1, 15 min after induction; T2, 20 min after insufflation; and T3, 5 min after de-insufflation., Results: PaO2 was significantly higher in group R than in group C (238 +/- 31 versus 196 +/- 32 mmHg, respectively, p = 0.015). PaCO2 rose gradually in both groups and the increase was significant between T1 and T2 (group C: 30 +/- 4 to 34 +/- 3 mmHg, p = 0.008; group R: 31 +/- 6 to 35 +/- 5 mmHg, p = 0.032). PvCO2 rose significantly in group C (39 +/- 4 to 42 +/- 4 mmHg, p = 0.001). The arteriovenous differences in CO2 increased in group C between T2 and T3 (6 +/- 3 to 11 +/- 6 mmHg) but the difference was not significant. PetCO2 increased after pneumo-peritoneum in group C (26 +/- 3 to 30 +/- 4 mmHg, p = 0.003). The arterial-PetCO2 gradient did not change., Conclusions: Laparoscopic cholecystectomy is a safe technique for use in patients with cardio-respiratory risk factors, even though there is a gradual increase in PaCO2. Physiological changes were greater in the patients with heart disease.

Published
1996

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