循环同化相控阵雷达数据模拟对流触发同化方案研究  

Research on convection initiation assimilation scheme by assimilating phased array radar observation

作　　者：龚澎 明杰[1,2,3] 吕迎辉 张强 GONG Peng;MING Jie;L Yinghui;ZHANG Qiang(Key Laboratory of Mesoscale Severe Weather of Ministry of Education,School of Atmospheric Sciences,Nanjing University,Nanjing 210023,China;Key Laboratory of Radar Meteorology,China Meteorology Administration,Nanjing 210023,China;Lianyungang Institute of High-Tech Research,Nanjing University,Jiangsu Lianyungang 222000,China;Meteorological Center of China Civil Aviation North China Air Traffic Management Bureau,Beijing 100621,China)

机构地区：[1]南京大学大气科学学院/中尺度灾害性天气教育部重点实验室,南京210023 [2]中国气象局雷达气象重点开放实验室,南京210023 [3]南京大学连云港高新技术研究院,江苏连云港222000 [4]中国民用航空华北地区空中交通管理局气象中心,北京100621

出　　处：《气象科学》2024年第1期115-124,共10页Journal of the Meteorological Sciences

基　　金：国家自然科学基金资助项目(41875053,42025501);中央高校基本科研业务费专项资金资助项目(020714380171,020714380177);灾害天气国家重点实验室开放课题(2021LASW-A01)。

摘　　要：利用WRF-EnKF同化系统,以2020年7月5日北京大兴发生的一次强对流天气背景下对流触发过程为个例,研究同化C波段相控阵雷达数据时更优的同化方案设置。本研究从同化频率、晴空数据处理阈值以及边界层杂波处理高度3个方面进行了研究。结果显示,高频同化可以抑制虚假回波,并有利于获得更准确的对流预报结果。将可靠晴空回波识别阈值设为-10 dBZ并剔除边界层内的低值回波可以有效改进对流触发的预报效果。为以后C波段相控阵雷达同化应用提供了新的同化方案思路。By using the WRF-EnKF assimilation system,taking a severe convective weather event occurred in Daxing,Beijing on July 5,2020 as an example,a more optimal assimilation scheme for assimilating C-band phased array radar data was investigated.This study analyzed three aspects:assimilation frequency,clear sky data processing threshold,and boundary layer clutter processing height.Results show that high-frequency assimilation can suppress false echoes and facilitate obtaining more accurate convective forecasting results.Setting the reliable clear sky echo recognition threshold to-10 dBZ and removing low value echoes within the boundary layer can effectively improve the prediction effect of convective triggering.This study provides a new assimilation scheme for the future application of C-band phased array radar.

关 键 词：WRF-EnKF 对流触发 同化方案 

分 类 号：P412.25[天文地球—大气科学及气象学]