红外卫星资料的云检测对台风数值模拟的影响

为提高红外卫星资料的利用率，需将更多的资料同化进入数值预报模式初始场，尽量减小云污染的影响。针对大气红外探测器(Atmospheric Infrared Sounder, AIRS)卫星资料，用云检测方法识别了云顶高度。在验证该方法的有效性之后，在大范围卫星视场的含云区域中保留所有云顶以上的通道，并将这些通道的亮温数据同化进入数值预报模式初始场，通过对比分析不同方案下台风的模拟路径来评估云检测方法对台风数值模拟的影响。结果表明，该云检测方法的效果较好，检测出的晴空区及云区的分布与实际观测对应，检测得到的高云顶区域与台风云系的对应性较好。将云顶以上的通道亮温加以利用后，红外卫星资料的利用率得到很大提高，数据是原数据量的2.4倍。在台风路径模拟方面，同化云层以上的通道数据后，数据量的增加使路径模拟变得更精确了，与观测值明显接近。

Influence of Cloud Detection of Infrared Satellite Data on Numerical Simulation of Typhoon

To improve the utilization of infrared satellite data, more data should be assimilated into the initial field of numerical forecasting mode so as to minimize the influence of cloud pollution. According to the data from Atmospheric Infrared Sounder (AIRS), a cloud detection method is used to identify Genting Height. After the validity of the method is verified, all of the channels above cloud top are retained in the cloud region of a large-scale satellite field of view and the brightness temperature data of these channels are assimilated into the initial field of the numerical prediction mode. By comparing and analyzing the simulated paths of the typhoon by different schemes, the influence of the cloud detection method on Typhoon numerical simulation is evaluated. The results show that the detection method is better in detection. The distribution of the clear sky and cloud area detected corresponds to the actual observation and the high cloud top area detected corresponds well to the typhoon cloud system. After the channel brightness temperature above cloud top is utilized, the utilization of infrared satellite data is improved greatly. The data utilized is 2.4 times as those of the original data. In typhoon path simulation, the increase in the amount of data makes the path simulation more accurate and is obviously close to the observed values after assimilation of above channel data.