Atmospheric influence on the deuterium excess signal in polar firn: implications for ice-core interpretation

• Published in: Journal of Glaciology
• Main Authors: Schlosser, Elisabeth, Oerter, Hans, Masson-Delmotte, Valerie, Reijmer, Carleen
• Other Authors: Leopold Franzens Universität Innsbruck - University of Innsbruck, Alfred Wegener Institute for Polar and Marine Research (AWI), 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), Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University Utrecht
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Austral; Dronning Maud Land; Neumayer; Neumayer Station; Antarc*; Antarctica; ice core; Journal of Glaciology
• Online Access: https://hal.archives-ouvertes.fr/hal-03103316; https://hal.archives-ouvertes.fr/hal-03103316/document; https://hal.archives-ouvertes.fr/hal-03103316/file/fichier6.pdf; https://doi.org/10.3189/002214308784408991

International audience The seasonal deuterium excess signal of fresh snow samples from Neumayer station, coastal Dronning Maud Land, Antarctica, was studied to investigate the relationship between deuterium excess and precipitation origin. An isotope model was combined with a trajectory model to determine the relative influence of different moisture sources on the mean annual course of the deuterium excess, focusing on the phase lag between d d 18 O and excess d. Whereas the annual course of d 18 O always shows an austral summer maximum, which clearly depends on local temperature and the annual course of moisture source-area parameters, the deuterium excess of the fresh snow samples shows maximum values already in spring. There can be many different reasons for the time lag between d 18 O and deuterium excess in an ice core, including post-depositional processes and changes in the moisture source of precipitation. The use of fresh snow samples enabled us to exclude post-depositional processes and study solely the influence of precipitation origin. Changes in the moisture source connected to systematic changes in the general atmospheric circulation can have a strong influence on the phase lag between deuterium excess and d 18 O, which has to be taken into account for climatic interpretation of stable-isotope profiles from ice cores.