应用常规探空、MP-3000A型地基微波辐射计和自动气象站数据，比较了微波辐射计与探空的差异，温度和相对湿度的平均观测偏差分别为3．2℃和29％，相关系数分别为0．98以上和0．5左右。分析了不同天气下微波辐射计的探测特征，发现相对湿度和液态水含量的垂直变化与降水、强对流和大雾的发生有良好对应：降水和强对流过程中，6 km以下的相对湿度提前增大（湿度增大的提前时间在降水中较长，在强对流中较短），3．5 km 以下液态水含量增加，尤其在2．25～3．25 km 处有明显的激增；大雾伴随3～3．5 km以下相对湿度增大和1．5 km以下液态水含量激增。A指数和对流性稳定指数（Iconve ）指数在出现明显降水后可能失去指示意义，在刚开始降水（尤其是明显降水）阶段及大雾中表现良好。%The difference and correlation between microwave radiometer and radiosonde are presented in this paper,based on conventional sounding,MP-3000A ground-based microwave radiometer and automatic station data.Result shows temperature and relative humidity differences from Suzhou ground-based micro-wave radiometer are 3.2℃ and 29% respectively,while correlation coefficients are above 0.98 and around 0 .5 accordingly.Analysis of signature for microwave radiometer observations in different weather condi-tions illustrates that there is a good correspondence between the vertical variations of relative humidity, liquid water content and the rainfall,severe weather,and fog.In precipitation and strong convection ca-ses,relative humidity below 6 km increases ahead of the weather process (lead time of increase in relative humidity in rainfall case is longer than that in severe convection case),liquid water content below 3 .5 km rises rapidly,especially in the height from 2.25 to 3.25 km.However,in fog cases,increase of relative humidity is below 3-3 .5 km and liquid water content is below 1 .5 km.A index and convective stability index may lost their indicative significance after obvious precipitation appears,but they perform well at the beginning of rainfall (especially remarkable rains)and in the fog case.
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