Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 7 7th Plinius Conference on Mediterranean Storms (2005) 2006 10.5194/adgeo-7-193-2006 http://www.adv-geosci.net/7/193/2006/ http://www.adv-geosci.net/7/193/2006/adgeo-7-193-2006.html http://www.adv-geosci.net/7/193/2006/adgeo-7-193-2006.pdf 193 198 2006-02-28 Evaluation of radiative transfer schemes for mesoscale model data assimilation: a case study A. Memmo C Faccani R. Ferretti S. Di Michele F. S. Marzano Centro di Eccellenza CETEMPS, Universit&#x00E0; dell’Aquila, L’Aquila, Italy Dipartimento di Fisica, Universit&#x00E0; dell’Aquila, L’Aquila, Italy Research Department, Satellite Section, European Centre for Medium-Range Weather Forecasts (ECMWF), Reading, UK Dipartimento di Ingegneria Elettronica Universit&#x00E0; di Roma "La Sapienza", Rome, Italy The assimilation of Special Sensor Microwave Imager (SSM/I) data into the Mesoscale Model 5 (MM5) allows for improving the weather forecast. However the results suggested an update the Radiative Transfer Equation (RTE) within the three-dimensional variational (3DVAR) algorithm which is tailored for non rainy conditions only. To this purpose, a new RTE algorithm is tested, in order to account for radiometric response in rainy regions. The new brightness temperatures (<i>T<sub>B</sub></i>) are estimated by using hydrometeor profiles from the MM5 mesoscale model, running with two different microphysical parameterizations. The goodness of the results is assessed by comparing the new <i>T<sub>B</sub></i> with those of the original RTE algorithm in the 3DVAR code and the SSM/I observed data. The results confirm a better reliability of the new RTE compared to the old one.