用红外云图估测小区域雨强及其在短时预报中的应用

INFRARED RAINFALL ESTIMATION TECHNIQUE FOR SMALL AREA AND ITS USE IN VERY SHORT-TERM WEATHER FORECASTING

在吸收国内外对卫星估测降水的经验和方法的基础上,利用深圳自动气象站网观测资料,对卫星云图资料进行分析、对比、反演,得到小区域红外云图对流云云顶亮温与降水强度的统计关系,建立了一个利用红外云图云顶亮温,结合空气水汽含量,云顶亮温的变化进行自动短时估测小区域对流云团降雨强度的方法;利用这种方法对深圳本地的短时强降雨的估测取得较好的效果。并在此基础上,运用云团移动外推的办法预测未来小区域云顶亮温的变化,从而进行短时对流降雨强度的预测。这对短时强对流降雨的预报和发布暴雨预警信号具有很好的参考价值。

We established a power law regression between the rainfall of the net of Shenzhen Automatic Weather Station and the satellite-derived IR top temperature of convective cloud collated in time and space. Based on the power law regression, we developed a technique to estimate the convective cloud rainfall intensity in small area which was adjusted by the growth rate correction factor and the moisture correction factor. The results showed that the convective cloud rainfall intensity estimates in SHENZHEN made by the technique were close to the reality. The technique can be useful in very short-term weather forecasting for the convective cloud by analyzing the cloud's moving speed and the change of satellite-derived IR cloud-top temperature.