Evaluation of radiative transfer schemes for mesoscale model data assimilation: a case study

摘要

The assimilation of Special Sensor Microwave Imager (SSM/I) data into theMesoscale Model 5 (MM5) allows for improving the weather forecast.However the results suggested an update the Radiative TransferEquation (RTE) within the three-dimensional variational (3DVAR) algorithmwhich is tailored for non rainy conditions only. To this purpose, a new RTEalgorithm is tested, in order to account for radiometric response in rainyregions. The new brightness temperatures (T_B) are estimated byusing hydrometeor profiles from the MM5 mesoscale model, running with twodifferent microphysical parameterizations. The goodness of the results isassessed by comparing the new T_B with those of the original RTEalgorithm in the 3DVAR code and the SSM/I observed data. The results confirma better reliability of the new RTE compared to the old one.