风廓线雷达资料反演雨滴谱和水汽通量的研究  

Retrieval and analysis of raindrop size distribution and water vapor flux based on wind profile radar data

作　　者：黄兴友[1] 何雨芩[1,2] 刘俊[1] 

机构地区：[1]南京信息工程大学中国气象局气溶胶-云-降水重点开放实验室,南京210044 [2]云南省气候中心,昆明650032

出　　处：《气象科学》2015年第6期751-759,共9页Journal of the Meteorological Sciences

基　　金：国家重点基础研究发展计划(973计划)项目(2013CB430101)

摘　　要：对2010年7月20日南京浦口地区发生的一次强降水过程,用WP-3000风廓线雷达反演了其雨滴谱分布和垂直水汽通量。并对雨滴谱进行了M-P指数拟合,求得了降水前期、中期、后期和即将停止时的浓度参数n0和尺度参数λ随高度的变化。同时利用该雷达反演了这次降水过程的回波强度、折射率结构常数和信噪比时间序列图,发现三者有很好的对应关系。结果显示:(1)n0和λ随着降水的发展而发生变化,n0在降水达到最强之前达到最大值,λ在降水最强时出现最小值;(2)n0在大气低层波动比高层明显,λ则在整层少有波动;(3)雨滴大小,随雨强的变化而变化,小雨滴数量多于大雨滴,但影响雨强的主要是大雨滴;(4)整个降水过程中近地面垂直水汽通量处在不断变化之中,但在雨后,表现为水汽向上输送。A WP-3000 wind profile radar data was used to retrieve the raindrop size distribution and vertical water vapor flux of a rainfall event in Pukou, Nanjing on July 20,2010. Moreover, the raindrop size distribution data was fitted in the form of Marshall-Palmer （M-P） exponential function to gain the variation of the concentration parameter no and shape parameter A with height before, during and after the rainfall. Meanwhile, the retrieval of echo intensity, refractive index structure constant and signal noise ra- tio（SNR） of time-series graph by the radar shows good consistence among them. Results show that （1）no and A change at different stages of rainfall, no reaches its maximum before rainfall, while A approaches to its minimum when rain intensity is the maximum. （2） no variation is more obvious at low level than at high level of atmosphere, while A seems invariant with height. （3）Rain droplet size changes with rain in- tensity, and small ones are much abundant than big ones, but big drops contributes more to rain intensity. （4）Near surface vertical water vapor flux often varies throughout the full period of rainfall, but after rain- fall, it transports upwardly.

关 键 词：雨滴谱反演 水汽通量反演 风廓线雷达 M-P指数拟合 

分 类 号：P412.25[天文地球—大气科学及气象学]