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List of Abstracts 170construct composite anomaly patterns of temperature, relative humidity, mass divergence, and ozone, from24 hours prior to the rainfall events to 24 hours after the rainfall events. The observed composite anomalypatterns are compared with those derived using data output from four general circulation models (AGCM3,AGCM4, GFDL2.1, ECHAM5) and two reanalysis products (ERA-40 and ERA-Interim). For the most part,the models do not realistically represent the mid-level warming, moistening, and divergence associated withcongestus clouds that precedes the rainfall maximum. The surface cold pool that develops about the strongprecipitation events is either not present, or is weaker than observations. In addition, the models do not fullyrepresent the mid-level stratiform convergence that follows the precipitation. The inability of models toreproduce these features suggests that the convective parameterizations used by the models and reanalysis donot realistically simulate the short timescale interactions between moist convection and the backgroundatmosphere.P-Observations 2.14 ID:4184 10:30Vertical ozone measurements in the troposphere over the Eastern Mediterranean basinPavlos Kalabokas 1 , Andreas Volz-Thomas 2 , Valerie Thouret 3 , Jean Pierre Cammas 3 , Damien Boulanger 3 ,Christos Repapis 11 Academy of Athens, Research Center for Atmospheric Physics and Climatology, Athens, Greece2 Institut fuer Chemie and Dynamik der Geosphaere, Forschungszentrum Juelich, Germany3 Laboratoire d’Aerologie, UMR 5560, Universite Paul Sabatier, Toulouse, FranceContact: kalabokas_pavlos@yahoo.grVertical ozone profiles measured in the period 1994–2008 in the framework of the MOZAIC project(Measurement of Ozone and Water Vapor by Airbus in Service Aircraft) for flights connecting CentralEurope to the Eastern Mediterranean basin (Cairo, Tel-Aviv, Heraklion and Rhodes, Antalya) were analyzedin order to evaluate the observed high rural ozone levels in the Mediterranean area during summertime. Intotal 237 summer (JJA) profiles were analyzed with the following distribution: Cairo, Egypt (94 profiles),Tel-Aviv, Israel (85 profiles), Heraklion-Rhodes, Greece (36 profiles) and Antalya, Turkey (22 profiles).This work is an extension of a previous study including 77 MOZAIC profiles collected in Heraklion, Rhodesand Antalya during the period 1996-2002 (June – September) so that to include the Middle-East region.In the lower troposphere and in the 1000-3000m layer the average profiles over Cairo and Tel-Aviv showcomparable values in the 60-72 ppb range, while the corresponding averages for Heraklion, Rhodes andAntalya are also quite comparable, though in the 55 – 62 ppb range. At all stations a rapid decrease of theaverage ozone mixing ratios is observed in the lowest 1000m, the sharpest decrease being observed at Tel-Aviv followed by Cairo, whereas the decrease is less significant at Heraklion, Rhodes and Antalya. Thesethree airports show the higher average values (50–55 ppb) in the surface layer below 500m than the Middle-East profiles. An examination of the average profiles for the 7% highest and the 7% lowest ozone mixingratios within the vertical interval 1000-1500m asl shows the following: a) profiles over Cairo, Heraklion, andRhodes show similar characteristics with large differences (40–50 ppb) between the minimum and maximumvalues, b) profiles over Antalya and Tel-Aviv exhibit smaller differences (20-30 ppb). An analysis ofcomposite weather maps for the high and low ozone cases as well as back-trajectories suggests that the mainfactor leading to high tropospheric ozone values in the area is the presence of anticyclonic conditionsespecially over the European continent transporting ozone and precursors, in association with subsidenceover Eastern Mediterranean. On the other hand, the lowest ozone levels are associated with low-pressureanomalies over the European continent leading to westerly circulation over Mediterranean towards theeastern region diffusing the air pollutants and also with extension of the Middle East low over the EasternMediterraneaniCACGP-IGAC 2010 14 July, 2010