ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-8-3963-2008 Probing ETEX-II data set with inverse modelling Krysta M. 1 2 4 Bocquet M. 1 2 Brandt J. 3 Université Paris-Est, CEREA, Research and Teaching Centre in Atmospheric Environment, Joint Laboratory École Nationale des Ponts et Chaussées/EDF R&D, 6–8 avenue Blaise Pascal, 77455 Champs sur Marne, France INRIA, Paris-Rocquencourt Research Centre, France Department of Atmospheric Environment, National Environmental Research Institute, Aarhus University, Frederiksborgvej 399, P.O. Box 358, 4000 Roskilde, Denmark currently at: Laboratoire Jean Kuntzmann, University of Grenoble, BP 53X, 38041 Grenoble cedex, France 24 07 2008 8 14 3963 3971 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/8/3963/2008/acp-8-3963-2008.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/8/3963/2008/acp-8-3963-2008.pdf

We give here an account on the results of source inversion of the ETEX-II experiment. Inversion has been performed with the maximum entropy method on the basis of non-zero measurements and in conjunction with a transport model POLAIR3D. The discrepancy scaling factor between the reconstructed and the true mass has been estimated to be equal to 7. The results contrast with the method's performance on the ETEX-I source. In the latter case its mass has been reconstructed with an accuracy exceeding 80%. The large value of the discrepancy factor for ETEX-II could be ascribed to modelling difficulties, possibly linked not to the transport model itself but rather to the quality of the measurements.

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