气象2017，Vol.43Issue(2)：166-180,15.DOI:10.7519/j.issn.1000-0526.2017.02.004
扰动变量在强对流天气分析和模式评估中的应用——以苏北里下河地区引发龙卷的扰动系统为例
Application of Anomalous Variables to Severe Convective System Analyses and Model Evaluation:A Case Study on Tornado-Producing Anomalous Systems near Lixia River,Jiangsu Province
摘要
Abstract
During 14:00-15:00 Beijing Time (BT)23 June 2016,an extremely tornado with the EF-4 scale hit the Funing County of Jiangsu Province,causing severe damages.Due to the topographic effect,11 tor-nado events were recorded causing more than 10 deaths in nearby region in the past 50 years,and 6 occurred after 1979.By decomposing model initial variables and model predicted outputs into temporal cli-matic state and anomaly,this paper first analyzed the 6 tornado events using observation data,finding that these tornadoes were associated with low-level negative anomalous height trough axes and clashes of anom-alous cold and warm air masses.Tornadoes always occur in the anomalous warm air mass.In the second half of the paper,the performances of ECMWF model and NCEP GFS on the tornado process on 23 June 2016 were evaluated using anomalous variables and indices.Analysis results at 14:00 BT illustrated that the tornado occurred at the intersection between a 925 hPa height anomaly trough and a maximum axis of moist vorticity anomaly and moist convergence anomaly at 850 hPa,respectively.The low-level moisture convergence and moist vorticity anomalies could well indicate the moisture and unstable condition for tor-nadogenesis.The ECMWF model well predicted the trough-axis feature for leading 42 h in advance while the NCEP GFS predicted for leading 18 h in advance,respectively.These anomalous variables and indices could help forecasters indicate a potential time-space domain of severe convective systems more quickly.关键词
龙卷风/扰动变量/次天气尺度系统/模式预报能力/评估Key words
tornado/anomaly-based variable/mesoscale system/model prediction/evaluation分类
天文与地球科学引用本文复制引用
钱维宏,梁卓轩,金荣花,符娇兰,吴芳芳,邝珠江,杜钧..扰动变量在强对流天气分析和模式评估中的应用——以苏北里下河地区引发龙卷的扰动系统为例[J].气象,2017,43(2):166-180,15.基金项目
公益性行业(气象)科研专项(GYHY20130613)资助 （气象）
