利用红外卫星云图资料估计降水量方法的研究

A STUDY ON THE METHODS FOR ESTIMATING RAIN AMOUNT FROM GEOSTATIONARY SATELLITE INFRARED IMAGES

在条件气候均匀及范围足够大取样区域，研讨面平均雨强与云覆盖率、云顶表面亮度温度的标准偏差、云覆盖率随时间的变化率三者之间的关系，得到用１ｈ间隔的数字化红外卫星资料估计降水的三种模式。通过对１９９１年７月５日、６日、１０日降水过程的实例分析表明，对于日降水量的估计，效果较为理想。模式可用于与取样时间和地点的相似气象条件区，且不需要对云进行分离和跟踪、考察对流单体的生命史演变过程，便于应用。

The relationship of the rainfall rate averaged over a sampling area, which is sufficiently large and conditionally homogeneous of climate, with the cloud coverage, standard deviation of the brightness temperatures at cloud top,and temporal variability of the cloud coverage, has been studied, and three statistical models are obtained for estimating rain amount with digitized, 1 h interval infrared images from geostationary satellite. The results from the precipitating weather on the 5th, 6th and 10th of July in 1991 show that the models are quite good at the estimation of daily precipitation. Because cloud isolation and tracking to examine the life stage are not necessary, the models are easy for applications and can be used in other areas as well provided the sampling time and meteorological conditions are similar.