关键词: 卫星资料同化, AMSU－A, 集合平方根滤波, 地表微波发射率

Abstract:

In order to investigate the possibility of improving initial fields of the model in the Yangtze and Huaihe river basin of China，based on RTTOV v10 ( Radiative Transfer for TOVS)model and its submodule named as the new surface microwave emissivity model，the simulated brightness observation data from the first channel of satellite AMSU － A under sunny and rainy weather conditions were assimilated into the weather research and forecasting ( WRF)model by using the ensemble square root filter ( EnSRF)．The results showed that，on sunny day，the analysis fields for the potential temperature，water vapor mixing ratio and horizontal wind speed u and v generally had been improved，but the improvements at different height levels were different．By comparison，the improvement of the horizontal wind speed was the maximum while that of the potential temperature was the minimum．For rainy weather condition，the effects of assimilation for the four analysis fields were approximately similar to that on sunny day．However，the spatial pattern of improvement on rainy day was different from that on sunny day．

Key words: satellite data assimilation, AMSU － A, EnSRF、surface microwave emissivity