Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 3 2007 10.5194/acpd-7-8795-2007 http://www.atmos-chem-phys-discuss.net/7/8795/2007/ http://www.atmos-chem-phys-discuss.net/7/8795/2007/acpd-7-8795-2007.html http://www.atmos-chem-phys-discuss.net/7/8795/2007/acpd-7-8795-2007.pdf 8795 8893 2007-06-25 MIPAS: an instrument for atmospheric and climate research H. Fischer M. Birk C. Blom B. Carli M. Carlotti T. von Clarmann L. Delbouille A. Dudhia D. Ehhalt M. Endemann J. M. Flaud R. Gessner A. Kleinert R. Koopmann J. Langen M. López-Puertas P. Mosner H. Nett H. Oelhaf G. Perron J. Remedios M. Ridolfi G. Stiller R. Zander Forschungszentrum Karlsruhe und Universität Karlsruhe, Institute for Meteorology and Climate Research, Karlsruhe, Germany Deutsches Zentrum für Luft- und Raumfahrt, Germany Istituto di Fisica Applicata, N. Carrara (IFAC) del Consiglio Nazionale delle Ricerche (CNR), Firenze, Italy Dipartimento di Chimica Fisica e Inorganica – University of Bologna, Bologna, Italy Groupe Infra-Rouge de Physique Atmosphérique et Solaire (GIRPAS), Département AGO, Université de Liège, Belgium Atmospheric, Oceanic and Planetary Physics, Clarendon Laboratory, Oxford University, United Kingdom Forschungszentrum Jülich, Institut für Atmosphärische Chemie, (ICG3), Jülich, Germany ESA/ESRIN, Frascati, Italy and ESA/ESTEC, Noordwijk, Netherlands Laboratoire Interuniversitaire des Systèmes Atmosphériques (LISA), CNRS, Université Paris VII et XII, France EADS Astrium GmbH, Friedrichshafen und München, Germany Instituto de Astrofísica de Andalucía (IAA), Granada, Spain ABB Bomem Inc., Quebec, Canada Earth Observation Science (EOS), Space Research Centre, Department of Physics and Astronomy, University of Leicester, UK MIPAS, the Michelson Interferometer for Passive Atmospheric Sounding, is a mid-infrared emission spectrometer which is part of the core payload of ENVISAT. It is a limb sounder, i.e. it scans across the horizon detecting atmospheric spectral radiances which are inverted to vertical temperature, trace species and cloud distributions. These data can be used for scientific investigations in various research fields including dynamics and chemistry in the altitude region between upper troposphere and lower thermosphere. The instrument is a well calibrated and characterized Fourier transform spectrometer which is able to detect many trace constituents simultaneously. The different concepts of retrieval methods are described including multi-target and two-dimensional retrievals. Operationally generated data sets consist of temperature, H2O, O3, CH4, N2O, HNO3, and NO2 profiles. Measurement errors are investigated in detail and random and systematic errors are specified. The results are validated by independent instrumentation which has been operated at ground stations or aboard balloon gondolas and aircraft. Intercomparisons of MIPAS measurements with other satellite data have been carried out, too. As a result, it has been proven that the MIPAS data are of good quality. MIPAS can be operated in different measurement modes in order to optimize the scientific output. Due to the wealth of information in the MIPAS spectra, many scientific results have already been published. They include intercomparisons of temperature distributions with ECMWF data, the derivation of the whole NOy family, the study of atmospheric processes during the Antarctic vortex split in September 2002, the determination of properties of Polar Stratospheric Clouds, the downward transport of NOx in the middle atmosphere, the stratosphere-troposphere exchange, the influence of solar variability on the middle atmosphere, and the observation of Non-LTE effects in the mesosphere. Allen, G.: The Infrared Remote Sensing of Peroxyacetyl Nitrate in the Upper Troposphere, Ph.D. thesis, University of Leicester, 2005. Andrews, A. 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