地形对登陆台风麦莎(2005)影响的数值模拟研究  

Numerical Simulation of the Impact of Terrain on Landfalling Typhoon Matsa(2005)

作　　者：季亮[1] 费建芳[1] 

机构地区：[1]解放军理工大学气象学院,南京211101

出　　处：《气象》2008年第6期60-66,共7页Meteorological Monthly

摘　　要：利用非静力平衡的中尺度模式MM5(V3)对2005年9号台风Matsa("麦莎")登陆后期的过程进行了48h模拟,应用低通滤波器分离模拟结果中的天气尺度和次天气尺度运动,并采用热带气旋动态坐标跟踪考察登陆过程中热带气旋的次天气尺度环流特征。通过研究地形对两种尺度间动能和涡度转换的影响,进一步证明了地形对热带气旋有着不可忽视的影响。结果表明,地形的存在有利于维持热带涡旋性强度,这种影响随气旋中心与地形间距离的缩小而逐渐增强,且强度的增强在对流层中高层表现得更为明显。去掉地形后对流层低层次天气尺度系统向热带气旋输送的动能减少,次天气尺度系统对热带气旋动能的消耗增大;当低层涡度转换项的垂直运动贡献为负时,去掉地形会加剧这种负贡献,即次天气尺度系统从热带气旋得到更多的正涡度;从整体上看,去掉地形后,热带气旋不仅没有从次天气尺度系统获得正涡度,反而将自身的正涡度向外输送。Using the Penn State-NCAR non-hydrostatic mesoscale model （MMS）, the later period of landfall of typhoon Matsa is simulated. A low-pass filter is used to separate the flow into a larg- er and a sub-synoptic scale component. Then the sub-synoptic scale features of Matsa were inves- tigated based on movable coordinate. From the view of the effect of terrain on the interactions between two scales, the influence of terrain on tropical cyclone is proved to be non-negligible further. The results are as follows; The existence of terrain helps to maintain the intensity of tropical cyclone and the effect intensifies with＇ the minishing of distance between the corner of cyclone and terrain. The intensification is more evident at upper troposphere. At low level the sub-synoptic system converts smaller kinetic energy into tropical cyclone and gets more kinetic energy from cyclone if terrain is taken out. Meanwhile, the sub-synoptic system gets more positive vertical vorticity from tropical cyclone. In a word, tropical cyclone dos not get but losses positive vertical vorticity if without terrain.

关 键 词：热带气旋 次天气尺度 动能转换 涡度转换 

分 类 号：P458.124[天文地球—大气科学及气象学] P458.121.1