基于COSMIC掩星资料的中国及周边地区云垂直结构特征研究  

Research of cloud vertical structure around China based on COSMIC occultation data

作　　者：韩丁[1] 严卫[1] 陆文[1] 刘会发[1] 

机构地区：[1]解放军理工大学气象海洋学院,南京211101

出　　处：《地球物理学进展》2013年第1期36-48,共13页Progress in Geophysics

基　　金：国家自然科学基金项目(41076118);国家自然科学基金青年基金项目(41005018)联合资助

摘　　要：利用2007年1月至2009年1月的气象、电离层及气候卫星探测系统(COSMIC)湿空气数据,基于相对湿度廓线出入云层时发生突变反演云边界高度进而获取云垂直结构参数的思想,对中国及周边八个不同地区云的垂直结构特征进行统计分析.结果表明:(1)不同地区掩星样本数随季节的变化较小,不同季节各地区间差异却较大,且多层云样本数日变化呈现明显的"双峰"结构;掩星最低探测高度集中在3.0km以下,各地区多层云受限制概率大于单层云,主要影响部分中低云参数的反演.(2)南方各地区云厚及晴空厚度都大于北方,双层云上层云厚大于下层,三层云从大到小依次为顶层、底层和中间层,且顶层与中间层晴空厚度大于中间层与底层;各地区不同季节内各层云云顶高具有相同的排列规律,云底高也基本遵循类似的排列顺序;多层云晴空厚度季节变化不显著,各季节内南方大于北方.(3)中国地区各类云云底高和云顶高二维频率季节变化不大,出现两个较大值区但分布高度各异;另外,南北方有不同的频率分布特点,其中西南和华南在16.0km以上出现"尾翼"分布,表明有深厚对流云产生.Based on the idea that getting cloud vertical structure （CVS） parameters from retrieved cloud boundary heights by using the mutation of relative humidity profile when it comes into or out of cloud, it gets the statistical analyses of cloud vertical structure in eight different districts around China by using COSMIC data from January 2007 to January 2009. The results show that： （1）Occultation sample number has little seasonal changes in different districts, but in different seasons there are large differences among different districts, and the number of multilayered clouds obeys ‘bimodal’ distribution apparently in daily variation. The minimum detecting altitude of COSMIC is lower than 3. 0km, and restricted probability of all multilayered clouds is larger than that of single layered clouds in each district, which mainly affects the retrieval of cloud parameters of part middle- and low-level clouds. （2）Cloud thickness and clear-sky distance in southern districts are larger than those in north, thickness of higher layer of two-layered clouds is also larger than that of lower layer and the descending order of three-layered clouds is highest, lowest and middle layer and the clear-sky distance between highest and middle is larger than that between middle and lowest. Cloud-top height of each layer in different seasons among eight districts has the same order and cloud-base height also basically obeys similar order, and clear-sky distance doesn＇t have significant seasonal changes and south is larger than north in each season. （3）Two-dimensional frequency distribution of cloud- base height and cloud-top height for different clouds has no obviously seasonal changes and it has two peak areas but the heights are different. There are different frequency distributions in south and north and Southwestern and South China appear ‘tail＇ distribution above 16.0km, which indicates that there are deep convective clouds occurring in these districts.

关 键 词：COSMIC 相对湿度 云垂直结构 多层云 云底高 云顶高 

分 类 号：TN95[电子电信—信号与信息处理] P426.5[电子电信—信息与通信工程]