Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 9 18 2009 10.5194/acp-9-6899-2009 http://www.atmos-chem-phys.net/9/6899/2009/ http://www.atmos-chem-phys.net/9/6899/2009/acp-9-6899-2009.html http://www.atmos-chem-phys.net/9/6899/2009/acp-9-6899-2009.pdf 6899 6913 2009-09-21 Technical Note: An assessment of the accuracy of the RTTOV fast radiative transfer model using IASI data M. Matricardi marco.matricardi@ecmwf.int ECMWF Shinfield Park, Reading, Berkshire, RG2 9AX, UK IASI measurements of spectral radiances made between the 1st April 2008 and the 15th April 2008 are compared with simulations performed using the RTTOV fast radiative transfer model utilizing regression coefficients based on different line-by-line models. The comparisons are performed within the framework of the European Centre for Medium-Range Weather Forecasts Integrated Forecast System using fields of temperature, water vapour and ozone obtained from short-range forecasts. 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