摘要
利用近岸海上气象平台对登陆台风＂黑格比＂近海层风廓线观测资料,计算分析了近海层大气的湍流动量通量交换参数,以期认识高风速情况下的海气动量交换特征。数据分析结果显示,当海面上方10 m处风速U10≤24 m/s时,摩擦速度（U＊）随风速的增大而增大,当U10〉24 m/s时,U＊呈饱和趋势。海面粗糙度长度（Z0）、拖曳系数（Cd）在低风速（U10≤6 m/s）随风速的增大而减小,在U10处于6~24 m/s之间时,Z0、Cd随风速的增大而增大,当U10〉24 m/s时,Z0、Cd达到极值后开始减弱。Z0、Cd极值出现在U10为24~28 m/s之间。并对高风速时拖曳系数衰减现象的对应机制进行了讨论。另外,还探讨了台风期间的阵风因子（G（t,T））等参数的演变特征。
In order to investigate the air-sea momentum exchange at high wind,the wind profile data observed in the atmospheric layer near the sea surface during the typhoon ＂Hagupit＂ are selected and analyzed.The results indicate that for 10 m wind speed U10≤ 24 m/s,the friction velocity U＊ increases with winds;as U10 is bigger than 24 m/s,U＊ shows a saturating tendency.The drag coefficient Cd and the roughness length Z0 decrease with increasing wind speed for U10 less than 6 m/s.For U10 between 6 m/s and 24 m/s,Z0 and Cd increase with wind speed.The maximum values of Z0 and Cd appear in the U10 range of 24~28 m/s.The possible mechanisms for the drag reduction at high wind speed are discussed.In addition,the gust factors G（t,T） during the typhoon are given and analyzed.
出处
《热带气象学报》
CSCD
北大核心
2011年第6期899-904,共6页
Journal of Tropical Meteorology
基金
973计划(2009CB421500)
国家自然科学基金重点项目(40730948)
行业专项(GYHY201106036)
公益性行业(气象)科研专项(GYHY200906008)
广东省自然科学基金(945100801900286)共同资助
关键词
边界层气象学
强风海气动量交换
拖曳系数
粗糙度长度
阵风因子
boundary layer meteorology
air-sea momentum exchange in strong wind
drag coefficient
roughness length
gust factor
