Aerosol Distribution Over the Western Mediterranean Basin During a Tramontane/Mistral Event
Ann. Geophys., 25, 2271–2291, 2007 www.ann-geophys.net/25/2271/2007/ Annales © European Geosciences Union 2007 Geophysicae Aerosol distribution over the western Mediterranean basin during a Tramontane/Mistral event T. Salameh1, P. Drobinski2, L. Menut1, B. Bessagnet3, C. Flamant2, A. Hodzic4, and R. Vautard5 1Institut Pierre Simon Laplace/Laboratoire de Met´ eorologie´ Dynamique, Ecole´ Polytechnique/ENS/UPMC/CNRS, Palaiseau, France 2Institut Pierre Simon Laplace/Service d’Aeronomie,´ UPMC/UVSQ/CNRS, Paris, France 3Institut National de l’Environnement Industriel et des Risques, INERIS, Verneuil en Halatte, France 4National Center for Atmospheric Research, Boulder, CO, USA 5Institut Pierre Simon Laplace/Laboratoire des Sciences du Climat et de l’Environnement, CEA/UVSQ/CNRS, Gif sur Yvette, France Received: 23 April 2007 – Revised: 4 October 2007 – Accepted: 18 October 2007 – Published: 29 November 2007 Abstract. This paper investigates experimentally and numer- clone position): The Tramontane wind prevails in the morn- ically the time evolution of the spatial distribution of aerosols ing hours of 24 March, leaving room for the Mistral wind over the Western Mediterranean basin during the 24 March and an unusually strong Ligurian outflow in the afternoon. 1998 Mistral event documented during the FETCH experi- The Genoa surface low contributes to advect the aerosols ment. Mistral and Tramontane are very frequently northerly along a cyclonic trajectory that skirts the North African coast wind storms (5–15 days per month) accelerated along the and reaches Italy. The wakes trailing downstream the Massif Rhoneˆ and Aude valleys (France) that can transport natural Central and the Alps prevent any horizontal diffusion of the and anthropogenic aerosols offshore as far as a few hundred aerosols and can, at times, contribute to aerosol stagnation.
[Show full text]