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List of Abstracts 211P-Observations 2.88 ID:4545 10:30A comparison of DOAS observations by the CARIBIC aircraft and the GOME-2 satellite of the 2008Kasatochi volcanic SO 2 plumeKlaus-Peter Heue 1 , Carl Brenninkmeijer 1 , Thomas Wagner 1 , Kornelia Mies 1 , Barbara Dix 2 , Udo Frieß 3 ,Bengt Martinsson 4 , Franz Slemr 1 , Peter Van Velthoven 51 Max Planck Institut für Chemie, Mainz, Germany2 Department of Chemistry and Biochemistry, University of Colorado, Boulder, USA3 Institut für Umweltphysik, Universität Heidelberg, Heidelberg, Germany4 Avdelningen för kärnfysik, Lunds universitet, Lund, Sweden5 Koninklijk Nederlands Meteorologisch Instituut (KNMI), De Bilt, the NetherlandsContact: Klaus-Peter.Heue@MPIC.deThe 2008 Kasatochi volcanic eruption emitted ≈1.5 - 2.5 Tg SO 2 into the upper troposphere and lowerstratosphere. Parts of the main volcanic plume (gases and particles) reached central Europe a week after theeruption and were detected there by the CARIBIC (Civil Aircraft for Regular investigation of theAtmosphere based on an Instrument Container) flying observatory. A detailed study on the CARIBICobservation of the plume will be given, focusing in the aerosol concentration and composition but mainly onthe DOAS observation of the SO 2 column densities. The Kasatochi eruption influenced the aerosolcomposition for at least three month.The plume was also observed by the GOME-2 satellite instrument, only a few hours after the CARIBICaircraft had crossed the plume, thus giving a unique opportunity to compare results. Trajectories and localwind speeds are investigated in detail using the GOME-2 and CARIBIC observations for better comparisonof the results from these two observational systems. A comparison of the spatial pattern with the localobservations of the wind speed and the trajectory models TRAJKS and HYSPLIT showed a slightdiscrepancy, which has to be considered for satellite validation. The online measured wind speed and winddirection agreed quite well with the model data, and therefore also led to the same discrepancy as themodels. Hence, it appears that detailed analyses of wind speeds are required.Emitted and secondary particles, partly measured and sampled by the CARIBIC in situ instruments, affectedthe DOAS SO 2 measurements, of both CARIBIC and GOME-2. Moreover the plume was situated above acloud by which the observed radiation and the column densities were strongly affected. Overall GOME-2and the CARIBIC SO 2 measurements agree very well. The major uncertainties remain the actual wind speedneeded to properly correct the advection of the plume between the different overpass times, and to smallerdegree the effect of clouds and aerosol.P-Observations 2.89 ID:4416 10:30Multi-component vertical profile retrievals for ground-based MAX-DOASHitoshi Irie 1 , Hisahiro Takashima 1 , Yugo Kanaya 1 , Michel Van Roozendael 2 , Folkard Wittrock 31 Japan Agency for Marine-Earth Science and Technology2 Belgian Institute for Space Aeronomy3 Institute of Environmental Physics, University of BremenContact: irie@jamstec.go.jpWe attempt to retrieve lower-tropospheric vertical profile information for 8 components from ground-basedMulti-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements. The componentsretrieved include aerosol extinction coefficients (AEC) at two wavelengths 357 and 476 nm, NO2, HCHO,CHOCHO, H2O, SO2, and O3 volume mixing ratios (VMRs). This method was applied to MAX-DOASobservations performed at Cabauw, the Netherlands (52.0ºN, 4.9ºE) in June- July 2009 during the CabauwiCACGP-IGAC 2010 14 July, 2010