2003年3月北大西洋上两个爆发性气旋的“吞并”过程及发展机制分析

本文利用欧洲中期天气预报中心(European Centre for Medium-Range Weather Forecasts,ECMWF)提供的0.125(°)×0.125(°)的ERA-Interim再分析资料、美国国家航空航天局(National Aeronautics and Space Administration,NASA)提供的MODIS(Moderate Resolution Imaging Spectroradiometer)可见光云图、气象卫星合作研究所(Cooperative Institute for Meteorological Satellite Studies,CIMSS)提供的GOES-EAST红外卫星云图等资料以及WRF(Weather Research and Forecasting)数值模式的模拟结果,对2003年3月北大西洋上一个爆发性气旋B“吞并”另一个气旋A后快速发展机制进行了分析。气旋A和B均生成于美国东部,气旋A于2003年3月5日06 UTC生成,气旋B于6日00 UTC生成,且比气旋A向东北方向移动得更快,7日18 UTC达到最大加深率3.27 hPa·h^-1。在北大西洋中部地区,从8日00 UTC开始,气旋B吞并气旋A后形成气旋C,8日12 UTC气旋C中心气压达到最低值938.3 hPa。高空急流、低空水汽输送和潜热释放为气旋A和气旋B的快速发展提供了有利的环流背景场。气旋B吞并气旋A的过程经历三个阶段:前期阶段、吞并阶段、完成阶段。利用WRF模式模拟结果的分析表明,气旋A和B之间建立水汽输运通道,水汽从气旋A向气旋B输送。气旋B吞并气旋A后形成气旋C快速发展的主要原因是暖平流的作用。

Analyses of Swallowing Process of Two Explosive Cyclones over the Northern Atlantic in March ,2003

In this paper,the swallowing process of two explosive cyclones over the Northern Atlantic in March 2003 are analyzed by using ERA-Interim data provided by ECMWF(European Centre for Medium-Range Weather Forecasts),EOSDIS(Earth Observing System Data and Information System)infrared satellite imagery and the modeling results of Weather Research and Forecasting(WRF)model.Initially,two cyclones A and B generated over the east of United States.Cyclone A was formed around 06 UTC 5 March 2003,and cyclone B was formed around 00 UTC 6 March,2003.Cyclone B moved northeastward faster than cyclone A.Around 18 UTC 7,cyclone B reached its maximum deepening rate of 3.27 hPa·h^-1.In central part of Northern Atlantic,cyclone B started to swallow cyclone A around 00 UTC 8.Cyclone C was formed after cyclone B swallowing cyclone A.Around 12 UTC 8,cyclone C reached its minimum central sea level pressure 938.3 hPa.The upper-level jet stream,low-level water vapor transport and latent heat release provided favorable conditions for the rapid development of both cyclones A and B.The process of cyclone B swallowing cyclone A may be classified into the following three stages the pre-swallowing stage,the swallowing stage and the final-swallowing stage.The diagnostic analyses based on WRF modeling results showed that a water vapor transport belt was established between cyclone A and cyclone B,and water vapor was transported from cyclone A to cyclone B.The warm advection seemed to be responsible for the rapid development of cyclone C after the cyclone B swallowing cyclone A.