Atmospheric Environment 39 (2005) 2933–2943 The vertical distribution of aerosol over Europe—synthesis of one year of EARLINET aerosol lidar measurements and aerosol transport modeling with LMDzT-INCA Sarah Guibert a,Ã , Volker Matthias b , Michael Schulz a , Jens Bo¨senberg c , Ronald Eixmann d , Ina Mattis e , Gelsomina Pappalardo f , Maria Rita Perrone g , Nicola Spinelli h , Geraint Vaughan i a Laboratoire des Sciences du Climat et de l’Environnement (LSCE), CEA-CNRS, IPSL, 91191 Gif-sur-Yvette, France b Institute for Coastal Research, GKSS Research Center, Geesthacht, Germany c Max-Planck-Institut fu¨r Meteorologie, Hamburg, Germany d Leibniz-Institut fu¨r Atmospha ¨renphysik, Ku¨hlungsborn, Germany e Leibniz-Institut fu¨r Tropospha¨renforschung, Leipzig, Germany f Istituto di Metodologie per l’Analisi Ambientale – CNR, Potenza, Italy g Dipartemento di Fisica – Universita´ di Lecce, Lecce, Italy h Istituto Nazionale per la Fisica della Materia and Dipartemento di Scienze Fisiche, Universita di Napoli, Italy i Physics Department of the University of Wales, Aberystwyth, UK Received 27 August 2004; accepted 22 December 2004 Abstract Aerosol extinction vertical profiles measured with Raman lidar in the framework of EARLINET in 2000 are compared to profiles modeled by a general circulation model, LMDzT-INCA, at seven stations in Europe. Comparisons based on individual profiles show moderate correlation between model and data. Averaging aerosol extinction values on larger temporal or spatial scales improves the comparison. Furthermore, we show that the model succeeds to reproduce the mean annual aerosol distribution over Europe. Comparisons of the aerosol vertical distribution in two distinct regions of Europe are presented. For the northern stations, the observed yearly average aerosol extinction coefficient vertical profile and the modeled one show an average bias of 22%. For the southern stations the mean bias is slightly higher (29%). Both model and lidar show different extinction profiles in different parts of Europe, with higher values in upper heights in the South. According to modeled profiles of each aerosol component, this is caused by the presence of dust at altitudes between 2 and 6 km. In addition vertical mixing in the South seems to be more effective for the other aerosol components. r 2005 Elsevier Ltd. All rights reserved. Keywords: Aerosol extinction; Vertical profiles; Aerosol composition; Saharan dust; GCM 1. Introduction Aerosol radiative forcing is one of the largest uncertainties in predicting climate change (Charlson ARTICLE IN PRESS www.elsevier.com/locate/atmosenv 1352-2310/$-see front matter r 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.atmosenv.2004.12.046 Ã Corresponding author. Tel.: +33169083999; fax: +33169083073. E-mail address: sarah.guibert@cea.fr (S. Guibert).