ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-7-1395-2007 MIPAS Level 1B algorithms overview: operational processing and characterization Kleinert A. 2 Aubertin G. 1 Perron G. 1 Birk M. 3 Wagner G. 3 Hase F. 2 Nett H. 4 Poulin R. 1 ABB Bomem Inc., 585 Blvd. Charest East, Québec, G1K 9H4, Canada Forschungszentrum Karlsruhe GmbH, Institut für Meteorologie und Klimaforschung, Postfach 3640, 76021 Karlsruhe, Germany Remote Sensing Technology Institute, German Aerospace Centre, Muenchner Str. 20, 82234 Wessling, Germany ESTEC, Kepplerlaan 1, Noordwijk, The Netherlands 28 02 2007 7 5 1395 1406 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/7/1395/2007/acp-7-1395-2007.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/7/1395/2007/acp-7-1395-2007.pdf

This paper gives an overview of the MIPAS Level 1B (L1B) processor whose main objective is to calibrate atmospheric measurements radiometrically, spectrally and geo-located. It presents also the results of instrument characterization done on ground and during the first years in-flight. An accurate calibration is mandatory for high quality atmospheric retrievals. MIPAS has shown very good performance and stability. The noise equivalent spectral radiance ranges from 3 to 50 nW/(cm<sup>2</sup> sr cm<sup>&minus;1</sup>) and is well within the requirements over nearly the whole spetral range. The systematic radiometric error is estimated to be within 1 or 2% in most situations.

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