同化卫星对地敏感通道微波亮温观测的模拟试验

借助快速辐射传输模式RTTOV v10（Radiative Transfer for TOVS）及其地表微波发射率模块,针对江淮区域晴天和雨天2类不同天气状况,采用理想试验手段,利用集合平方根滤波（En SRF）方法同化AMSU-A对地敏感第1通道的模拟亮温资料,探究改善中尺度模式WRF（Weather Research and Forecasting）初始场的可行性。结果表明：晴天时,同化对位温、水汽混合比及水平风速u和v整体上均有不同程度的改善,但不同高度改善程度有所差异,相对而言水平风场的改进程度最大,位温最小;有降水时,4个要素场整体改进程度与晴天时类似,但分析场误差的水平空间分布与晴天时不同。

A Simulation Experiment of Assimilating Microwave Brightness Observations at the Sensitive Channel to Land

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（ En SRF）. 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.