Gas Extraction From Polar Ice Cores: A Critical Issue For Studying The Evolution of Atmospheric CO2 and Ice-Sheet Surface Elevation

• Published in: Annals of Glaciology
• Main Authors: Raynaud, Dominique, Delmas, Robert, Ascencio, Jean-Marc, Legrand, Michel
• Other Authors: 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)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 1982
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Annals of Glaciology; Ice Sheet
• Online Access: https://hal.science/hal-03512164; https://hal.science/hal-03512164/document; https://hal.science/hal-03512164/file/gas-extraction-from-polar-ice-cores-a-critical-issue-for-studying-the-evolution-of-atmospheric-co2-and-ice-sheet-surface-elevation.pdf; https://doi.org/10.3189/S0260305500002895

International audience The measurement of gases enclosed in polar ice cores provides valuable Information concerning the history of the 1ce sheets and their environment. The extraction of gases from ice is a critical step in the experimental procedure. We found that the most efficient methods of gas extraction for 20 to 50 g samples were ice melting and controlled refreezing of the melt water for the total gas content and ice crushing far the CO2 content. These two experimental methods are described in detail. It is shown, in particular, that ice is easily contaminated by carbonate dust during sample preparation. This contamination introduces an excess of CO2 when gases are extracted using a procedure involving ice melting.