Major 20th century changes of the content and chemical speciation of organic carbon archived in Alpine ice cores: Implications for the long-term change of organic aerosol over Europe

• Published in: Journal of Geophysical Research: Atmospheres
• Main Authors: Legrand, Michel, Preunkert, Susanne, May, B., Guilhermet, J., Hoffman, H., Wagenbach, D.
• Other Authors: Laboratoire de glaciologie et géophysique de l'environnement (LGGE), 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), Technische Physik, Julius-Maximilians-Universität Würzburg Wurtzbourg, Allemagne (JMU), Institut für Umweltphysik Heidelberg, Universität Heidelberg Heidelberg
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2013
• Subjects: [SPI.MECA.STRU]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Structural mechanics [physics.class-ph]; ice core
• Online Access: https://hal.archives-ouvertes.fr/hal-02045607; https://hal.archives-ouvertes.fr/hal-02045607/document; https://hal.archives-ouvertes.fr/hal-02045607/file/Legrand2013.pdf; https://doi.org/10.1002/jgrd.50202

International audience Dissolved organic carbon (DOC) and an extended array of organic compounds were investigated in an Alpine ice core covering the 1920-1988 time period. Based on this, a reconstruction was made of the long-term trends of water-soluble organic carbon (WSOC) aerosol in the European atmosphere. It is shown that light mono-and dicarboxylates, humic-like substances, and formaldehyde account together for more than half of the DOC content of ice. This extended chemical speciation of DOC is used to estimate the DOC fraction present in ice that is related to WSOC aerosol and its change over the past. It is suggested that after World War II, the WSOC levels have been enhanced by a factor of 2 and 3 in winter and summer, respectively. In summer, the fossil fuel contribution to the enhancement is estimated to be rather small, suggesting that it arises mainly from an increase in biogenic sources of WSOC.