台风同心双环云墙的演变

本文利用飞机探测资料，分析了台风同心双环云墙演变的特征。在1949—1985年的83个同心双眼台风中，双环云墙的演变可分为以下三类。1.随着台风的加强，包围眼的云墙直径逐渐缩小，而外围又会涌入一圈环状闭合云墙，外云墙也逐渐缩小，内云墙很快消失。在这类台风变化过程中，会有几次外围涌入环状云墙的情况；与此相对应，台风强度变化有一振荡。2.另一类台风在变化过程中，外围涌入环状云墙只有一次。外云墙发展变化较复杂:有的台风外云墙会渐渐缩小；有的外云墙会渐渐扩展；有的双环云墙维持较长一段时间；有的外云墙出现后很快消失。3.还有一类双环云墙的形成是由台风眼内积云对流发展而演变为环状闭合内云墙的，这类台风的内云墙维持一段时间后即消散。

The Evolutioin of Double-ring Cloud Wall of Concentric Eye Typhoons

By using aircraft sounding data (1949—1985) of 83 typhoons, the evolution of the double-ring cloud wall of concentric eye typhoons are analysed. It is found that there are three types of evolution: ① In the first type, accompanying the increase of typhoon intensity with time, the diameter of cloud wall encircled the original eye region of typhoon gradually shrinks. Meanwhile, a new cloud wall occur in the periphery of the region and then invade inward. So a double-ring cloud wall is formed. Then the inner wall rapidly disappears and the outer wall gradually shrinks. Usually, several processes similar to the above evolution may occur successively and the intensity of typhoon would oscillate with time. ② In the second type, a closed cloud wall occurs and invades from the periphery of the typhoon eye region. The evolution of the outer cloud wall is quite complex. It may sometimes shrink, and sometimes extend. In some cases the double-ring cloud wall lasts for a period of time, and in other cases its outer wall disappears rapidly. ③ In the third type, the double-ring cloud wall is formed as a result of the development of cumulus convection inner region of typhoon into a well-closed inner cloud wall. The inner wall usually lasts for a period of time and then rapidly disappears.