【摘要】 利用青海省东部地区2018年7—9月、2019年4—9月、2020年4—7月FY-2G卫星反演的云特征参量及地面小时降水数据,分析了云顶高度、云顶温度、云光学厚度和云粒子有效半径4种云特征参量对降水频率及降水强度的指示性。结果表明:(1)单云特征参量中,云光学厚度对降水频率指示性最强。中雨、大雨频率分别随云顶温度下降、云顶高度及云光学厚度增加呈明显增加趋势,而小雨频率随之呈减小趋势。(2)双云特征参量(云光学厚度和云顶温度)对降水频率指示性优于单云特征参量,降水频率随云光学厚度增加及云顶温度下降而增大。当云光学厚度为21～30且云顶温度大于0℃时,小雨频率最大。云光学厚度大于40且云顶温度为-45～-31℃时,中雨频率最大。云光学厚度大于40且云顶温度小于-45℃时,大雨频率最大。(3)三云特征参量(云顶温度、云光学厚度和云粒子有效半径)对降水频率指示性优于单云特征参量,但比双云特征参量降水频率指示性弱。更多还原

【Abstract】 Based on the cloud characteristic parameters retrieved by FY-2 G satellite and hourly precipitation from July to September 2018, April to September 2019, and April to July 2020 in the eastern region of Qinghai Province, the indications of cloud top height, cloud top temperature, cloud optical thickness and cloud particle effective radius to precipitation frequency and precipitation intensity were analyzed. The results are as follows:(1) The cloud optical thickness was the strongest indicator of precipitation frequency for single cloud characteristic parameter. The frequency of moderate rain and heavy rain showed an obvious increasing trend with the decrease of cloud top temperature, increase of cloud top height and cloud optical thickness, while the frequency of light rain showed a decreasing trend.(2) The double cloud characteristic parameters(cloud optical thickness and cloud top temperature) were better indicators for precipitation frequency than single cloud characteristic parameter, the precipitation frequency increased with increase of cloud optical thickness and decrease of cloud top temperature. When cloud optical thickness was between 21 and 30 and cloud top temperature was greater than 0 ℃, the frequency of light rain was largest. When cloud optical thickness was greater than 40 and cloud top temperature was between-45 and-31 ℃, the frequency of moderate rain was largest. When cloud optical thickness was greater than 40 and cloud top temperature was less than-45 ℃, the frequency of heavy rain was largest.(3) The triple cloud characteristic parameters(cloud top temperature, cloud optical thickness and cloud particle effective radius) were more indicative for precipitation frequency than single cloud characteristic parameter and less indicative than double cloud characteristic parameters.更多还原