ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-8-18091-2008 Measurements of Pollution In The Troposphere (MOPITT) validation through 2006 Emmons L. K. 1 Edwards D. P. 1 Deeter M. N. 1 Gille J. C. 1 Campos T. 1 Nédélec P. 2 Novelli P. 3 Sachse G. 4 National Center for Atmospheric Research, Boulder, CO, USA Laboratoire d'Aérologie, University P. Sabatier, Centre National de la Recherche Scientifique, Observatoire Midi-Pyrénées, Toulouse, France NOAA, Earth System Research Laboratory, Global Monitoring Division, Boulder, CO, USA NASA Langley Research Center, Hampton, VA, USA 15 10 2008 8 5 18091 18109 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-discuss.net/8/18091/2008/acpd-8-18091-2008.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/8/18091/2008/acpd-8-18091-2008.pdf

Comparisons of aircraft measurements of carbon monoxide (CO) to the retrievals of CO using observations from the Measurements of Pollution in The Troposphere (MOPITT) instrument onboard the Terra satellite are presented. Observations made as part of the NASA INTEX-B and NSF MIRAGE field campaigns during March–May 2006 are used to validate the MOPITT CO retrievals, along with routine samples from 2001 through 2006 from NOAA and the MOZAIC measurements from commercial aircraft. A significant positive bias, around 20% for total column CO, in MOPITT CO was found in the comparison to in situ measurements during 2006. Comparisons to the long-term records of measurements from NOAA and MOZAIC revealed an increasing bias in the V3 MOPITT CO retrievals over time. Possible causes for the drift have been investigated and should be significantly reduced in the next version (V4) of MOPITT retrievals.

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