Modelling the response of stable water isotopes in Greenland precipitation to orbital configurations of the previous interglacial

• Published in: Tellus B: Chemical and Physical Meteorology
• Main Authors: Sjolte, Jesper, Hoffmann, Georg, Johnsen, Sigfús Jóhann
• Other Authors: Niels Bohr Institute Copenhagen (NBI), Faculty of Science Copenhagen, University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Lund University Lund, Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), 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)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2014
• Subjects: stable water isotopes; modelling; moisture source; seasonality; previous interglacial; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology; [SDU.STU.ME]Sciences of the Universe [physics]/Earth Sciences/Meteorology; Arctic; Greenland; Antarc*; Antarctica; Climate change; ice core
• Online Access: https://hal.archives-ouvertes.fr/hal-03212967; https://hal.archives-ouvertes.fr/hal-03212967/document; https://hal.archives-ouvertes.fr/hal-03212967/file/Modelling%20the%20response%20of%20stable%20water%20isotopes%20in%20Greenland%20precipitation%20to%20orbital%20configurations%20of%20the%20previous%20interglacial.pdf; https://doi.org/10.3402/tellusb.v66.22872

International audience The relation between δ 18O of precipitation and temperature has been used in numerous studies to reconstruct past temperatures at ice core sites in Greenland and Antarctica. During the past two decades, it has become clear that the slope between δ 18O and temperature varies in both space and time. Here, we use a general circulation model driven by changes in orbital parameters to investigate the Greenland δ 18O–temperature relation for the previous interglacial, the Eemian. In our analysis, we focus on changes in the moisture source regions, and the results underline the importance of taking the seasonality of climate change into account. The orbitally driven experiments show that continental evaporation over North America increases during summer in the warm parts of the Eemian, while marine evaporation decreases. This likely flattens the Greenland δ 18O response to temperature during summer. Since the main climate change in the experiments occurs during summer this adds to a limited response of δ 18O, which is more strongly tied to temperature during winter than during summer. A south–west to north–east gradient in the δ 18O–temperature slope is also evident for Greenland, with low slopes in the south–west and steeper slopes in the north–east. This probably reflects the proportion of continental moisture and Arctic moisture arriving in Greenland, with more continental moisture in the south–west and less in the north–east, and vice versa for the Arctic moisture.