摘要
台风Winnie 1997的眼直径为370 km,是有观测以来发现的最大台风眼之一。应用Penn State/NCAR高分辨率中尺度模式MM5,成功地模拟了Winnie的路径、强度、台风眼及其双眼壁结构。由此根据模式输出结果分析了台风眼及内外眼壁附近的流场和热力场特征。发现Winnie台风的眼壁及其周围风场都显示了明显的非对称性结构。Winnie的外眼壁对应一个极大风速环,也是暖湿环和正涡度环。内眼壁对应一个次极大风速环、暖湿环。上升运动控制整个内眼壁和海平面2 km以上的外眼壁区域,下沉运动则控制眼区和内外眼壁之间。径向入流集中在外眼壁和内外眼壁之间的边界层,流出则位于外眼壁的对流层中上层。
Typhoon Winnie 1997 was one of the hurricanes that had extremely largest eyewall ever recorded. The diameter of Winnie＇s eyewall reached 370 km. Using the Penn State University/National Center for Atmospheric Research mesoscale model MM5 with 3 km grid horizontal spacing on the finest nested mesh, Winnie was successfully simulated in terms of track, intensity, eye and concentric eyewalls. The dynamic and thermal structure of concentric eyewalls was studied based on the model output. It was found that the concentric eyewalls was asymmetric both in observation and simulation. Winnie＇s outer eyewall was associated with a maximum wind ring, a warm moist ring and a high voticity ring. The inner eyewall was associated with a secondary maximum wind ring and a warm moist ring. Upward motion dominated the whole layer of inner eyewall and the area above 2 km altitude of the outer eyewall. Downward motion was found inside the eye and the moat. Radial inflow happened at the boundary layer of the outer eyewall and the moat, but radial outflow dominate the middle and upper level of the outer eyewall.
出处
《气象学报》
CAS
CSCD
北大核心
2006年第2期180-185,i0001,共7页
Acta Meteorologica Sinica
基金
国家科技部973项目(2004CB418301)
国家自然科学基金项目(40375017和40233036)
