ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-9-897-2009 Global temperature estimates in the troposphere and stratosphere: a validation study of COSMIC/FORMOSAT-3 measurements Kishore P. 1 Namboothiri S. P. 2 Jiang J. H. 3 Sivakumar V. 4 5 Igarashi K. 2 Dept. of Physics and Atmospheric Science, Dalhousie University, Halifax, Canada National Institute of Information and Communications Technology, Tokyo, Japan Jet Propulsion Laboratory, Pasadena, CA, USA National Laser Centre, CSIR, Pretoria, South Africa Department of Geography, Geoinformatics and Meteorology, University of Pretoria, South Africa 04 02 2009 9 3 897 908 Copyright: © 2009 P. Kishore et al. 2009 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/articles/9/897/2009/acp-9-897-2009.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/9/897/2009/acp-9-897-2009.pdf

This paper mainly focuses on the validation of temperature estimates derived with the newly launched Constellation Observing System for Meteorology Ionosphere and Climate (COSMIC)/Formosa Satellite 3 (FORMOSAT-3) system. The analysis is based on the radio occultation (RO) data samples collected during the first year observation from April 2006 to April 2007. For the validation, we have used the operational stratospheric analyses including the National Centers for Environmental Prediction - Reanalysis (NCEP), the Japanese 25-year Reanalysis (JRA-25), and the United Kingdom Met Office (MetO) data sets. Comparisons done in different formats reveal good agreement between the COSMIC and reanalysis outputs. Spatially, the largest deviations are noted in the polar latitudes, and height-wise, the tropical tropopause region noted the maximum differences (2–4 K). We found that among the three reanalysis data sets the NCEP data sets have the best resemblance with the COSMIC measurements.

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