多源数据融合在强对流天气中地面风场的识别应用  

Application of Multi-Source Data Fusion in SurfaceWind FieldIdentification in Severe ConvectiveWeather

作　　者：王子昕 王咏青[1,2] 张静 王易[3] WANG Zixin;WANG Yongqing;ZHNG Jing;WANG Yi(Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory of Meteorological Disasters,Ministry of Education/School of Atmospheric Sciences,Nanjing University of Information Science&Technology,Nanjing 210044,Jiangsu,China;Nanjing Joint Center of Atmospheric Research,Nanjing 210009,Jiangsu,China;Jiangsu Meteorological Observatory,Nanjing 210008,Jiangsu,China)

机构地区：[1]南京信息工程大学气象灾害预报预警与评估协同创新中心/气象灾害教育部重点实验室/大气科学学院,江苏南京210044 [2]南京大气科学联合研究中心,江苏南京210009 [3]江苏省气象台,江苏南京210008

出　　处：《高原气象》2022年第3期790-802,共13页Plateau Meteorology

基　　金：广东省重点领域研发计划项目(2020B1111200001);国家重点研发计划项目(2018YFC1506103);国家自然科学基金项目(41875070);北极阁开放研究基金项目(NJCAR2018MS02)。

摘　　要：利用多普勒天气雷达探测数据、常规观测资料和ERA5再分析资料,综合分析了2019年7月6日发生在江苏省的一次强对流天气过程的天气形势和雷达回波强度演变特征,并进行了多源数据融合的试验。试验通过VAP技术将雷达径向速度数据反演为矢量风场,并利用典型相关分析的方法(CCA)对雷达径向速度资料反演的风场、再分析资料的风场和气象自动站资料的风场进行数据融合。通过风场融合试验,获得了强对流系统更加丰富准确的地面风场信息,与雷达探测的特征对应,消除了反演风场的量级误差,填补了被过滤的风场信息,恢复了气流的旋转特征。强对流天气过程中,江苏省地区受高空冷涡影响,在高空冷槽、高空急流、低层切变线和地面辐合线的配置条件下,形成了上干冷、下暖湿的层结不稳定结构。通过融合风场的识别:强对流天气系统发展阶段,地面有气旋性辐合流场,包含中γ尺度气旋和辐合线,与反气旋和辐散相伴。气旋性气流对应着雷达回波中的入流缺口,辐合线位于风暴前沿(移动方向)。强对流天气系统强盛阶段,地面流场转变为强辐合弱旋转,灾害性天气发生。Based on the detection data of doppler weather radar combined with the conventional observation data and the EAR5 reanalysis data,this paper comprehensively analyzes the synoptic environment and the evolution characteristics of radar reflectivity,and a test of multi-source data fusion is conducted during a severe convective weather process occurred in Jiangsu Province on 6 July 2019.VAP(velocity azimuth processing)technology is used to retrieve the radial velocity data into vector wind field.The wind field retrieved by radial velocity and the wind fields of reanalysis data and automatic weather station data are fused by the canonical correlation analysis(CCA)method.By wind field fusion test,more abundant and accurate surface wind field information of the severe convection system is obtained,which corresponds to the characteristics of the data detected by doppler weather radar.After data fusion,the magnitude error of retrieval wind field is eliminated,the filtered wind field information is filled,and the rotation characteristics of airflow are restored.In the process of the severe convective weather,Jiangsu Province is affected by the high-altitude cold vortex.Under the conditions of high-altitude cold troughs,high-altitude jet stream,low-level shear lines and surface convergence lines,an unstable stratification with upper dry cooling and lower warm and humid formation is formed.The results of the fusion wind fields show that in the development stage of the strong convection weather system,there are cyclonic convergence flow fields on the surface,includingγ-mesoscale cyclones and convergence lines,accompanied by anticyclonic and divergent flows.The cyclonic flow field corresponds to the position of the inflow gap in the radar echo field,and the convergence lines are located at the region of the storm front(moving direction).In the strong stage of the strong convective weather system,the surface flow field changes into a strong convergence and weak rotation attitude.At the same time,the disastrous weather occurs.

关 键 词：风场反演 数据融合 地面风场 旋转辐合 

分 类 号：P458.2[天文地球—大气科学及气象学]