The Cryosphere Discussions www.the-cryosphere-discuss.net 1994-0432 1994-0440 6 1 2012 10.5194/tcd-6-171-2012 http://www.the-cryosphere-discuss.net/6/171/2012/ http://www.the-cryosphere-discuss.net/6/171/2012/tcd-6-171-2012.html http://www.the-cryosphere-discuss.net/6/171/2012/tcd-6-171-2012.pdf 171 210 2012-01-19 Statistical adaptation of ALADIN RCM outputs over the French alpine massifs – application to future climate and snow cover M. Rousselot marie.rousselot@gmail.com Y. Durand G. Giraud L. Mérindol I. Dombrowski-Etchevers M. Déqué Météo-France/CNRS, CNRM-GAME URA 1357, France In this study, snowpack scenarios are modelled across the French Alps using dynamically downscaled variables from the ALADIN Regional Climate Model (RCM) for the control period (1961–1990) and three emission scenarios (SRES B1, A1B and A2) by the mid- and late of the 21st century (2021–2050 and 2071–2100). These variables are statistically adapted to the different elevations, aspects and slopes of the alpine massifs. For this purpose, we use a simple analogue criterion with ERA40 series as well as an existing detailed climatology of the French Alps (Durand et al., 2009a) that provides complete meteorological fields from the SAFRAN analysis model. The resulting scenarios of precipitation, temperature, wind, cloudiness, longwave and shortwave radiation, and humidity are used to run the physical snow model CROCUS and simulate snowpack evolution over the massifs studied. The seasonal and regional characteristics of the simulated climate and snow cover changes are explored, as is the influence of the scenarios on these changes. Preliminary results suggest that the Snow Water Equivalent (SWE) of the snowpack will decrease dramatically in the next century, especially in the Southern and Extreme Southern part of the Alps. 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