摘要
利用FY—2E和CloudSat卫星、多普勒雷达、T639L60物理量、雷电及实测降水等资料,分析了2010年7月19日、8月4日和21日渤海西海岸大暴雨天气的中尺度云团时空分布。结果表明,从红外云图、水汽云图与6h雨量叠加可明显看出有多个β、γ中尺度云团,并以50～60km·h-1的速度沿副热带高压588dagpm线西北侧的引导气流方向移动,强降水时段TBB温度值为-96～-115℃,涡旋状云系对应低层中尺度低涡,带状云系对应低层中尺度切变线。同步雷达反演显示,β中尺度对流云团强、弱交替变化周期为3～6h,天津地区减弱的雨团移到河北海岸带,在有利的低层风场辐合区产生了新的暴雨云团;该暴雨云团减弱后,对下游锦州上空的中尺度雨团发展是一个快速波动传输过程,且与多单体风暴的传播机理相似。闪电频数与强降水时段的峰值较一致,中小尺度雨团合并和低层辐合是造成短时强降水的原因之一。
Using the FY-2E satellite and CloudSat, Doppler radar and T639L60 model data, as well as lightning and the synchronous precipitation data, the time and space distributions of the mesoscale cloud clusters are analyzed off the west coast belt of Bohai Sea during three rainstorm on July 19, on August 4, and on August 21, 2010. Some conclusions are obtained, for instance, many of meso-β scale and meso-γ scale cloud clusters can be found in infrared image and in water vapor image overlapping with rainfall in 6 h, and they moved along the steering airflow direction at 50~60 km· h^- 1 on the western edge of the 5 880 dagpm of the subtropical anticyclone, the temperature of black body is from --96 to --115℃ in the rain- storm process. The vortex nephsystem is connected to the mesoscale vortex in the low-level wind field, the banded clouds related to mesoscale shear line in the low layer. The synchronous inversion of radar echo that the alternate change of meso-γ scale convective cloud clusters between the strong and weak is from 3 to 6 h. The spatial structure of meso-β scale and meso-γ scale are always changed mutually, the convergent region of lower-level wind field in specific environments will create new rainstorm clusters. The peak value of lightning frequency and rainfall period is consistent, the merger of medium and small scale rain cluster and low-layer convergence is one of the causes for short-term rainfall.
出处
《高原气象》
CSCD
北大核心
2013年第3期818-828,共11页
Plateau Meteorology
基金
公益性行业项目“黄渤海高影响天气预报中的关键技术研究”(GYHY201106006)
河北省气象局科研开发项目“渤海强对流天气监测与预报预警技术研究”(2011ky30)共同资助
关键词
中尺度雨团
对流降水
渤海西海岸带
Mesoscale rain cluster
Convective precipitation
Off the west coast belt of Bohai Sea
