基于CloudSat卫星资料分析东太平洋台风的云、降水和热力结构特征  

Analyzing Cloud, Precipitation, and Thermal Structure Characteristics of Typhoons in Eastern Pacific Based on CloudSat Satellite Data

作　　者：韩丁[1] 严卫[1] 叶晶 刘会发[1] 

机构地区：[1]解放军理工大学气象海洋学院 [2]解放军95871部队

出　　处：《大气科学》2013年第3期691-704,共14页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金资助项目41076118;41005018

摘　　要：利用2006～2010年的CloudSat热带气旋过境数据集资料,依据风速大小划分为不同演变阶段,对各阶段内东太平洋台风的云、降水和热力结构进行综合分析。结果表明:雷达反射率在5km高度上下的分布截然相反,沿径向回波强度和顶高不断减小。各类云沿径向和垂直方向的分布差异较大,而深对流云的垂直尺度和发生概率始终较大。有效粒子半径、分布宽度参数和冰水含量随高度减小而粒子数浓度却增大,沿径向各冰云参数以及降雨率都不断减小。各阶段降雨率总体上夏季大于秋季,沿纬向各季节在不同阶段的分布各异。内核区降雨率近似服从指数分布且对暖的海面温度SST较为敏感,其与雷达反射率的散点分布集中在三个区域内。内核区5～10km高度存在暖核结构,其下方恰好对应湿心区,而10km以上相对湿度距平较大值区对应台风顶部的卷云罩。各阶段4.5km以上为对流性稳定层结而该高度以下的层结特性各异,此外假相当位温沿径向不断减小。Using the CloudSat tropical cyclone crossing dataset from 2006 to 2010 and dividing the data into different evolutionary stages according to wind speed, the cloud, precipitation, and thermal structure characteristics of typhoons at different stages in the eastern Pacific are comprehensively analyzed. The results show that radar reflectivity has opposite distributions above and below 5 km in height, and the echo intensity and top height decrease along the radial direction. Large differences appear between the distribution of different types of clouds along the radial and vertical directions, and the vertical scale and occurrence probability of deep convective clouds are always large. The effective radius, distribution width parameter, and ice water content decrease but the particle number concentration increases as the height increases. Each ice cloud parameter and the rainfall rate decrease gradually along the radial direction. The rainfall rate at each stage in summer is generally larger than that in autumn, and along the latitudinal direction in each season, it varies within different stages. The rainfall rate in the inner core area follows a nearly exponential distribution and is sensitive to warmer sea surface temperatures, and its scatter plot with radar reflectivity converges in three regions. There is a hot corestructure at 5-10 km in height in the inner core area; below it a wet core area exists, whereas an area with a larger anomaly in the relative humidity corresponds to the cirrus canopy at the top of the typhoon. Atmospheric stratification is convectively stable above 4.5 km in height at each stage; below that, it varies between stages, and the pseudo-equivalent potential temperature decreases along the radial direction.

关 键 词：CLOUDSAT 台风 雷达反射率 降雨率 热力结构 

分 类 号：P426[天文地球—大气科学及气象学]