1Max-Planck-Institut für Chemie (MPI), Mainz, Germany
2Department of Chemistry and Biochemistry, University of Colorado, Boulder, USA
3Institut für Umweltphysik, Universität Heidelberg, Heidelberg, Germany
4Avdelningen för kärnfysik, Lunds universitet, Lund, Sweden
5Koninklijk Nederlands Meteorologisch Instituut (KNMI), De Bilt, The Netherlands
6Leibniz-Institut für Troposphärenforschung, Leipzig, Germany
7Institut für Meteorologie und Klimaforschung (IMK) Karlsuhe Insitute of Technology, Karlsruhe, Germany
8Institut für Küstenforschung, GKSS, Geesthacht, Germany
Abstract. The ash cloud of the Eyjafjallajökull1 volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) flying laboratory, which routinely measures at cruise altitude (≈11 km) performed three dedicated measurements flights through sections of the ash plume. Although the focus of these flights was on the detection and quantification of the volcanic ash, we report here on sulphur dioxide (SO2) and bromine monoxide (BrO) measurements with the CARIBIC DOAS (Differential Optical Absorption Spectroscopy) instrument during the second of these special flights on 16 May 2010. As the BrO and the SO2 observations coincide, we assume the BrO to have been formed inside the volcanic plume. Both SO2 and BrO observations agree well with simultaneous satellite (GOME-2) observations. SO2 column densities retrieved from satellite observations are often used as an indicator for volcanic ash. For SO2 some additional information on the local distribution can be derived from a~comparison of forward and back scan GOME-2 data. More details on the local plume size and position are retrieved by combining CARIBIC and GOME-2 data.
1Also referred to as: Eyjafjalla (e.g. Schumann et al., 2010), Eyjafjöll or Eyjafjoll (e.g. Ansmann et al., 2010).