涡区 meaning in English

vortex region
wake

The analysis of dry pv shows that the high pv dominate the area of typhoon , the higher is the center value of pv , the stronger is the typhoon . lt is also shown that the most important reason resulting in rainstorm is the cold air ( high pv ) which spreads to south from the upper troposphere or lower stratosphere and transports into the warm air . the joining situation of upper and lower pv area make vortex develop . pv transpotation reduces static stability , which increases the releasing of instability energy and makes rainstorm amplify
对干位涡的分析表明：台风或台风环流区为高值位涡区，台风越强，位涡中心值越大；对流层上部或平流层下部冷空气(高位涡)的扩散南下与暖湿气流的交汇是造成特大暴雨的重要原因，因为上游斜压性的发展使对流层顶发生折叠，平流层与对流层相互作用增强，上下位涡区相接的形势使低层涡旋发展，上升运动加强，位涡的下传有效地降低了静力稳定度，有利于位势不稳定能量的释放，使得暴雨增幅。