摘要
利用S波段双偏振雷达(SPOL)、X波段相控阵雷达(XPAR)两种新一代天气雷达观测数据,采用多普勒雷达风场反演技术,对2021年5月18日厦门市局地短时强降水过程进行分析。结果表明:(1)此次过程发生在低空西南急流和冷空气交汇影响区域内,低层风速的脉动及列车效应是局地短时强降水发生发展的重要因素。(2)雷达对比分析显示,SPOL显示更杂乱,垂直结构分辨率低,存在低层盲区,但能较好地捕捉到强降水的云微物理特征,还清楚地显示了两个较强降水阶段的特征差异;XPAR则可以清晰显示回波单体生成发展的演变过程。利用XPAR雷达组网,可以有效地提高SPOL低层盲区观测能力。XPAR也同时出现了回波偏强、强回波后的衰减、速度图中大风区的表现欠佳及强回波高度较低、垂直结构中双偏振特征与回波特征对应度较差等问题。两个雷达对回波悬垂、弱回波区的ZDR柱及强回波中心低层ZDR跃增均有体现。(3)多雷达风场反演结果显示,强回波上游形成的明显辐合导致不断有新生单体形成并向下游移动,促进列车效应的加强。同时进一步证实,在较强的西南暖湿气流环境下,列车效应中沿回波传播方向的垂直运动会呈现出上升-下沉运动交替出现的传播性波动特征。
Based on the observation data of two new generation weather radars,S-band dual polarization radar(SPOL)and X-band phased array radar(XPAR),and the wind field retrieval technology of Doppler radar,analysis was carried out on the local short-time severe precipitation process in Xiamen on May 18,2021.The results indicate that:(1)The process took place in the area affected by the low-level southwest jet and the cold air confluence.The fluctuation of low-level wind speed and the train effect are the important factors for the occurrence and development of local short-term severe precipitation.(2)Comparative analysis of radar data shows that the SPOL display is more disordered,the resolution of vertical structure is lower and there is a low-level blind area,but it can better capture the cloud microphysical characteristics of severe precipitation and it also can clearly reveal the difference of the characteristics between the two heavy precipitation stages.XPAR can show the evolution of the formation and development of echo cell clearly.Using the XPAR networking can effectively improve the capability of SPOL in observing the low-level blind area.At the same time,XPAR has some problems as well,including strong radar echo,attenuation after strong echo,poor performance in strong wind area in velocity diagram,low height of strong echo,and poor correspondence between dual polarization and echo characteristics in vertical structure.The two radars both show the echo overhang,the ZDR column in the weak echo zone and the ZDR jump in the lower layer of the strong echo center.(3)The results of multi-radar wind field retrieval indicate that the obvious convergence which was formed in the upwind of strong echoes leads to the formation of new cells and their moving to downwind direction,which promotes the strengthening of train effect.Meanwhile,it is further confirmed that in the strong southwest warm-humid airflow environment,the vertical movement along the echo propagation direction in the train effect will show the propagation fluc
作者
张妤晴
张伟
郑辉
荀爱萍
李菲
Zhang Yuqing;Zhang Wei;Zheng Hui;Xun Aiping;Li Fei(Xiamen Key Laboratory of Straits Meteorology,Xiamen 361012,China;Xiamen Meteorological Observatory,Xiamen 361012,China)
出处
《气象与环境科学》
2023年第4期85-94,共10页
Meteorological and Environmental Sciences
基金
福建省自然科学基金项目(2021J01463)
福建省气象局开放式基金项目(2021K02、2021K03)
厦门市科学技术局指导性项目(3502Z20214ZD4008、3502Z20214ZD4009)。
关键词
S波段双偏振雷达
X波段相控阵雷达
局地短时强降水
列车效应
反演风场
S-band dual polarization radar
X-band phased array radar
local short-time severe precipitation
train effect
retrieval of wind field
