Global Long-Term MIPAS Data Processing

The Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) was a Fourier transform mid-infrared limb scanning high resolution spectrometer which allowed for simultaneous measurements of more than 30 atmospheric trace species related to atmospheric chemistry and global change. MIPAS on Envisat was operated by ESA since mid of 2002 through April 8th 2012, when, due to a power supply failure, the platform and all onboard instruments were lost. At the Institute for Meteorology and Climate Research (IMK), MIPAS spectra are used for retrieval of altitude-resolved profiles of abundances of trace species of the atmosphere. The vertical profiles processed at IMK are available to external data users since many years. The trace gas distributions are used for the assessment of e.g. stratospheric ozone chemistry, stratospheric cloud physics and heterogeneous chemistry, stratospheric exchange processed with troposphere and mesosphere, intercontinental transport of pollutants in the upper troposphere, effects of solar proton events on stratospheric chemistry, thermosphere temperature, and chemistry-climate models. In the reporting period 2012/2013 most CPU time of MIPAS data processing on the XC4000 supercomputer was used for retrievals including computationally expensive NLTE calculations. This comprises the kinetic temperature for several special high altitude observation modes of MIPAS, NO, CO and NO2 volume mixing ratios. Most of the processing work was done in close collaboration with the Instituto de Astrofísica de Andalucía (IAA) in Granada, Spain. Two examples of scientific exploitation of this kind of data will be given: 1. Determination of the NOx-production rate and the NOx-lifetime during the solar proton event in October–November 2003. 2. The Impact of two solar proton events in 2012 on chemistry and dynamics of the middle atmosphere at the northern and southern polar caps have been examined using MIPAS data of temperature and several species.