Solar and proxy-sensitivity imprints on paleohydrological records for the last millennium in west-central Europe

Michel Magny (1) , Fabien Arnaud (2) , H. Holzhauser (3) , Emmanuel Chapron (4) , Maxime Debret (4) , Marc Desmet (5) , A. Leroux (1) , Marie Revel (6) , Boris Vannière (1) , Laurent Millet (1)

1 LCE - Laboratoire Chrono-environnement (UMR 6249)
2 EDYTEM - Environnements, Dynamiques et Territoires de Montagne
3 Ahornstrasse
4 ISTO - Institut des Sciences de la Terre d'Orléans
5 ACCES-INRP
6 GEOAZUR 6526 - Géoazur

This paper presents a lake-level record established for the last millennium at Lake Saint-Point in the French Jura Mountains. A comparison of this lake-level record with a solar irradiance record supports the hypothesis of a solar forcing of variations in the hydrological cycle linked to climatic oscillations over the last millennium in west-central Europe, with higher lake levels during the solar minimums of Oort (around AD 1060), Wolf (around AD 1320), Spörer (around AD 1450), Maunder (around AD 1690), and Dalton (around AD 1820). Further comparisons of the Saint-Point record with the fluctuations of the Great Aletsch Glacier (Swiss Alps) and a record of Rhône River floods from Lake Bourget (French Alps) give evidence of possible imprints of proxy sensitivity on reconstructed paleohydrological records. In particular, the Great Aletsch record shows an increasing glacier mass from AD 1350 to 1850, suggesting a cumulative effect of the Little Ice Age cooling and/or a possible reflection of a millennial-scale general cooling until the mid-19th century in the Northern Hemisphere. In contrast, the Saint-Point and Bourget records show a general trend toward a decrease in lake levels and in flood magnitude anti-correlated with generally increasing solar irradiance.

Mots clés: Lake levels; River discharge; Glacier fluctuations; Last millennium; Solar forcing; Jura Mountains; Central; NW Alps

Domaines: Interfaces continentales, environnement; Milieux et Changements globaux

Michel Magny, Fabien Arnaud, H. Holzhauser, Emmanuel Chapron, Maxime Debret, et al.. Solar and proxy-sensitivity imprints on paleohydrological records for the last millennium in west-central Europe. Quaternary Research, 2010, 73 (2), pp.173-179. ⟨10.1016/j.yqres.2009.11.006⟩. ⟨insu-00446080⟩