DOI:10.1016/j.yqres.2012.03.003 1400 years of extreme precipitation patterns over the Mediterranean French Alps and possible forcing mechanisms

• Main Authors: Bruno Wilhelm, Fabien Arnaud, Pierre Sabatier, Christian Crouzet, Elodie Brisset, Jean-robert Disnar, Frederic Guiter, Emmanuel Malet, Jean-louis Reyss, Edouard Bard, Jean-jacques Delannoy
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2013
• Subjects: North Atlantic; North Atlantic oscillation
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.401.7126; http://hal-sde.archives-ouvertes.fr/docs/00/71/99/73/PDF/Wilhelm_et_al_QR_2012_revised2-1.pdf

Investigation of Lake Allos sediments revealed ~160 graded layers, interpreted as flood deposits, over the last 1400 yr. Comparisons with records of historic floods support the interpretation of flood deposits and suggest that most recorded flood events are the result of intense meso-scale precipitation events. As there is no evidence for any major changes in erosion processes in the catchment since the Medieval Warm Period (MWP), we interpret the Allos record in terms of repeated intense precipitation events over the last millennium, with a low flood frequency during the MWP and more frequent and more intense events during the Little Ice Age. This interpretation is consistent with the halsde-00719973, version 1- 17 May 2013 pattern of increasingly humid conditions in the northwestern Mediterranean region. This long-term trend is superimposed on high frequency oscillations that correlate with solar activity and autumnal North Atlantic Oscillation (NAO). Finally, a comparison of flood records across the northwestern