中文摘要：

使用新一代中尺度WRF模式对2005年台风Matsa（麦莎）登陆后的变化特征进行了数值模拟;对其登陆后强度持续维持的机理作了初步探讨;对登陆后涡动动能收支作了诊断分析。台风“麦莎”登陆后长久维持与以下因素密切相关。（1）持续的水汽输送通道。“麦莎”登陆后两条持续维持的水汽输送通道将暖湿空气源源不断地送入台风,为“麦莎”的维持提供了潜热能。（2）增强的高层辐散风场。200 hPa附近的辐散风场随着时间的增加而增强,所产生的“抽吸”作用和“减压”作用,对“麦莎”环流和强度的维持起到了重要的作用。（3）长久剧烈的上升运动。“麦莎”登陆后一直保持着剧烈的上升运动,强烈的上升运动把低层的暖湿空气向上输送,为“麦莎”的维持提供热能和动能。（4）活跃的中尺度扰动。“麦莎”的螺旋云带中活跃着中尺度对流系统,它们在低层所产生的较强辐合作用对“麦莎”气旋式环流的维持起到了正反馈作用。（5）涡动动能收支的诊断分析表明,“麦莎”登陆后,地形等摩擦作用和水平输送使其能量耗损,垂直通量散度项使其能量增加,平均动能与涡动动能之间的转换项是涡动动能收支中的相对小项;但随着时间的增加摩擦动能耗散作用逐渐减小,“麦莎”从中高层环境中获得了能量,涡动动能的增加从高层开始逐渐向中低层传播。

英文摘要：

Numerical simulation has been carried out to investigate the evolution characteristics of typhoon Matsa of 2005 after its landfaUing by using the new generation of meso-scale weather research and forecasting （WRF） model. Meanwhile, a preliminary study has been also made on the mechanism of the sustaining of Matsa＇s intensity in parallel with diagnostic analyses of eddy kinetic energy （EKE） budget. The results show that the sustaining of typhoon Matsa after landfalling is closely associated with the following factors： （1） Existence of two moisture channels,through which warm and moist air was continuously transported to typhoon Matsa with the maximum water vapor flux being about 20 × 10^4 g/（s·hPa·cm）. （2） Enhanced divergent wind fields in the upper troposphere, whose ＂pumping＂ played an important role in the sustaining of the circulation and intensity of Matsa. （3） Sustained vigorous ascending motion, which transported the warm and moist air in the lower troposphere upwards to release latent heat and thus to provide kinetic energy for Matsa＇s sustaining. （4） Active meso-scale cyclonic vortices embedded in the spiral cloud bands of Matsa, which induced some strong meso-scale ascending motion and low level cyclonic convergence, playing a role of positive feedback to the sustaining of Matsa＇s intensity. （5） Gaining EKE from the environmental flow fields in the middle and upper troposphere. Diagnostic analyses on. the EKE budget indicate that the EKE in lower levels was dissipated by the frictional effect of terrain and horizontal advection, enhanced by the divergence of the vertical flux of EKE. After Matsa＇s land- fall, the generation term of EKE was positive at almost all levels with the maximum at about 200 hPa, and provided a lot of EKE for Matsa＇s sustaining. The conversion between mean kinetic energy and EKE was a quantity of lower order in the EKE budget. Furthermore, the frictional dissipation of EKE gradually decreased with time while Matsa increasingly gai