摘要
利用NCEP/NCAR提供的全球客观分析资料对1409号超强台风＂威马逊＂近海急剧加强的特征进行了诊断分析。结果表明：南海较高的海表温度、中低层丰富的水汽净流入为＂威马逊＂增强提供了有利的能量条件;维持近22h对流层深层、高层及低层介于0~4m/s弱环境风垂直切变是＂威马逊＂两次以超强台风登陆的必要条件;台风中心附近对流层高层强烈辐散、中低层正涡度值的增大和正涡度柱向对流层上层的伸展导致＂威马逊＂急剧增强;＂威马逊＂台风急剧增强具有一定前兆性,急剧增强与环境风垂直切变及对流层中低层涡度值的响应时间分别为12h和9h。
Based on the NCEP/NCAR reanalysis data,the characteristics of Rammasun over the offshore of China are analyzed using the synoptic and dynamic diagnosis methods.The results show that high SST in the South China Sea and the abundant water vapor transport at lower and middle levels provided favorable energy for the intensification of Rammasun;weak vertical environmental wind shear between 0to 4ms-1 at lower,middle,and upper levels,which maintained nearly 22 hour,was a necessary condition for supertyphoon Rammasun landing two times;strong divergence at the upper level,positive vorticity which enlarged at the lower level,and the positive vorticity column stretched to the upper troposphere resulted in Rammasun increased sharply;there was a time lag of about 12 hours between the vertical wind shear change and the typhoons rapid intensity change;and the changing of vorticity at the lower troposphere was also about 9hours earlier than typhoon strengthening.
出处
《气象科技》
北大核心
2015年第6期1149-1156,共8页
Meteorological Science and Technology
基金
柳州市应用气象研究与开发计划项目(2011J020107)资助
关键词
超强台风
近海
强度变化
Super Typhoon
offshore
intensity change
