ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-9-413-2009 Validation of version-4.61 methane and nitrous oxide observed by MIPAS Payan S. 1 Camy-Peyret C. 1 Oelhaf H. 2 Wetzel G. 2 Maucher G. 2 Keim C. 2 Pirre M. 3 Huret N. 3 Engel A. 4 Volk M. C. 4 Kuellmann H. 5 Kuttippurath J. 5 16 Cortesi U. 6 Bianchini G. 6 Mencaraglia F. 6 Raspollini P. 6 Redaelli G. 7 Vigouroux C. 8 De Mazière M. 8 Mikuteit S. 2 Blumenstock T. 2 Velazco V. 5 Notholt J. 5 Mahieu E. 9 Duchatelet P. 9 Smale D. 10 Wood S. 10 Jones N. 11 Piccolo C. 12 Payne V. 13 Bracher A. 5 Glatthor N. 2 Stiller G. 2 Grunow K. 14 Jeseck P. 1 Te Y. 1 Butz A. 15 Laboratoire de Physique Moléculaire pour l'Atmosphère et l'Astrophysique, Université Pierre et Marie Curie-Paris 6, Paris, France Institut für Meteorologie und Klimaforschung, Forschungszentrum Karlsruhe, Karlsruhe, Germany Laboratoire de Physique et Chimie de l'Environnement/CNRS, Orléans, France Institut für Atmosphäre und Umwelt, J. W. Goethe Universität Frankfurt, Frankfurt, Germany Institute of Environmental Physics/Institute of Remote Sensing, University of Bremen, Bremen, Germany Istituto di Fisica Applicata "Nello Carrara", Sesto Fiorentino, Italy Università di L'Aquila, Dipartimento di Fisica, L'Aquila, Italy Belgian Institute for Space Aeronomy, Brussels, Belgium Institut d'Astrophysique et de Géophysique, University of Liège (ULg), Liège, Belgium National Institute for Water and Atmospheric Research (NIWA), Lauder, Otago, New Zeeland University of Wollongong, Wollongong, Australia Atmospheric, Oceanic and Planetary Physics, Department of Physics, Oxford University, Oxford, UK Atmospheric and Environmental Research, Inc, Lexington, Massachusetts, USA Meteorologisches Institut der FU Berlin, Berlin, Germany Institut für Umweltphysik, University of Heidelberg, Germany now at: Laboratoire de Météorologie Dynamique, Ecole Polytechnique, Palaiseau, France 19 01 2009 9 2 413 442 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/9/413/2009/acp-9-413-2009.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/9/413/2009/acp-9-413-2009.pdf

The ENVISAT validation programme for the atmospheric instruments MIPAS, SCIAMACHY and GOMOS is based on a number of balloon-borne, aircraft, satellite and ground-based correlative measurements. In particular the activities of validation scientists were coordinated by ESA within the ENVISAT Stratospheric Aircraft and Balloon Campaign or ESABC. As part of a series of similar papers on other species [this issue] and in parallel to the contribution of the individual validation teams, the present paper provides a synthesis of comparisons performed between MIPAS CH<sub>4</sub> and N<sub>2</sub>O profiles produced by the current ESA operational software (Instrument Processing Facility version 4.61 or IPF v4.61, full resolution MIPAS data covering the period 9 July 2002 to 26 March 2004) and correlative measurements obtained from balloon and aircraft experiments as well as from satellite sensors or from ground-based instruments. In the middle stratosphere, no significant bias is observed between MIPAS and correlative measurements, and MIPAS is providing a very consistent and global picture of the distribution of CH<sub>4</sub> and N<sub>2</sub>O in this region. In average, the MIPAS CH<sub>4</sub> values show a small positive bias in the lower stratosphere of about 5%. A similar situation is observed for N<sub>2</sub>O with a positive bias of 4%. In the lower stratosphere/upper troposphere (UT/LS) the individual used MIPAS data version 4.61 still exhibits some unphysical oscillations in individual CH<sub>4</sub> and N<sub>2</sub>O profiles caused by the processing algorithm (with almost no regularization). Taking these problems into account, the MIPAS CH<sub>4</sub> and N<sub>2</sub>O profiles are behaving as expected from the internal error estimation of IPF v4.61 and the estimated errors of the correlative measurements.

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