海南地区山体地形对地闪回击定位精度的影响  

Effect of Mountainous Terrain on Lightning Return Strokes Location Accuracy in Hainan

作　　者：邹斌[1,2,3,4] 崔海华 张其林[1,2,3,4] 李静[1,2,3,4] 戴炳哲 姚年鹏 蒋尧 杨敢 罗华 ZOU Bin;CUI Hai-hua;ZHANG Qi-lin;LI Jing;DAI Bing-zhe;YAO Nian-peng;JIANG Yao;YANG Gan;LUO Hua(Key Laboratory of Meteorological Disaster, Ministry of Education, Nanjing University of Information Science and Technology, Nanjing 210044, China;Joint International Research Laboratory of Climate and Environment Change, Nanjing University of Information Science and Technology, Nanjing 210044, China;Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disaster, Nanjing University of Information Science and Technology, Nanjing 210044, China;Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing 210044, China;Hebei Meteorological Administrative Technology Service Center, Shijiazhuang 050000, China)

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室,南京210044 [2]南京信息工程大学气候与环境变化国际合作联合实验室,南京210044 [3]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,南京210044 [4]南京信息工程大学中国气象局气溶胶与云降水重点开放实验室,南京210044 [5]河北省气象行政技术服务中心,石家庄050000

出　　处：《科学技术与工程》2021年第28期11989-11998,共10页Science Technology and Engineering

基　　金：国家重点研发计划(2017YFC1501505);国家自然科学基金面上项目(41775006);河北省重点研发计划(19275409D)。

摘　　要：为了将地形地貌带来的误差进行修正,提高闪电的探测效率和定位精度,基于二维时域有限差分法(finite difference time domain,FDTD),构建了真实地形下的雷电电磁波传播模型,研究了海南地区地形对雷电电磁波传播的影响,然后提出了一种修正闪电定位误差的方法即不同步长的地形包络和时间补偿法。模拟结果表明:山地地形会明显改变切向磁场的波形峰值大小和上升沿时间,与平坦地表情况相比,切向磁场波形峰值变化最大的减小了38%,上升沿时间增加范围在1~3μs,峰值到达时间也滞后于平地情况,而经过滤波处理,磁场峰值减小,波形变陡,上升沿时间变短;对于逐峰法,雷击点在真实地形路径下定位误差相比平地明显增大很多;而对于互相关算法,真实地形路径下定位误差比平地情况下大,但相差不大,相比逐峰法定位误差明显大很多;总体来说,使用5 km包络修订效果较好,定位误差都在百米量级内,相比较其他算法闪电定位精度有很大提高。In order to correct the errors caused by topography and improve the detection efficiency and positioning accuracy of lightning,based on the two-dimensional finite-difference time-domain method(FDTD),a lightning electromagnetic wave propagation model under real terrain was constructed,the influence of the mountainous terrain in Hainan Province on the lightning electromagne-tic wave propagation was studied,and then the asynchronous long terrain envelope and time compensation method to correct the lightning positioning error was proposed.The simulation results show that mountain terrain significantly changes the peak size and rising edge time of the tangential magnetic field.Compared with the change that happens under the flat surface conditions,the maximum change in tangential magnetic field waveform peaks decreases by 38%,the rising edge time increase ranges from 1 to 3μs,peak arrival time lags behind that of the flat conditions,and after filtering wave treatment,magnetic field peak decreases,waveform becomes steep,rising edge time is reduced.In terms of the peak-by-peak method,the positioning error of lightning strike points in the real terrain path is significantly larger than that of the flat ground,while in terms of the interrelated algorithm method,the positioning error under the real terrain path is larger than that in the flat-ground situation,but the difference between the two positioning errors is not significant,for the positioning error caused by the peak-by-peak method larger.Overall,the use of 5 km envelope gets better revision effect,positioning errors are within the 100 meters magnitude,for compared with other algorithms lightning positioning accuracy has been greatly improved.

关 键 词：时域有限差分(FDTD) 真实地形 雷电电磁场传播 闪电定位 

分 类 号：P401[天文地球—大气物理学与大气环境]