基于宁波多普勒雷达、浙江省自动气象站、宁波凉帽山高塔梯度观测等资料,对1416号强热带风暴“凤凰”登陆浙江后的风场时空变化进行分析.结果表明:“凤凰”结构不对称,8级以上风速带主要位于风暴中心前进方向的前侧和右侧.前侧最大风速半径一直维持在60 km左右,最大风速带宽度约为50 km;其右侧最大风速半径为80～120km,随中心北移有增大趋势,最大风速带宽度约100km;其前侧和右侧最大风速半径在垂直方向上变化不大.“凤凰”前侧TREC(Tracking Radar Echoes by Correlation)风速在1km高度最强,其上则随高度的增大而减小,其右侧1～3 km高度TREC风速的垂直变化明显小于前侧.宁波凉帽山高塔处TREC风和梯度观测表明:“凤凰”影响期间,高塔上空159m和2～4 km高度出现多个风速高值中心;常通量层高度约为159m;常通量层内风廓线遵从对数率,当高塔位于“凤凰”右前侧时塔层阵风系数随高度增大而减小,当高塔位于“凤凰”中心附近和右后侧时阵风系数明显增大,且层次差异减小;常通量层以上159～318m的塔层风廓线不满足指数率或对数率,阵风系数上下差异不大.
WIND EVOLUTION CHARACTERISTICS OF SEVERE TROPICAL STORM FUNG WONG (1416) AFTER MAKING LANDFALL IN ZHEJIANG PROVINCE
By using the observation data from a Doppler radar at Ningbo,automatic weather stations in Zhejiang Province,and an observation tower on the Hill Liangmaoshan at Ningbo,a comprehensive analysis was conducted on the wind field evolution of the severe tropical storm (STS) Fung Wong (1416) after its landfall in Zhejiang Province.Results show that Fung Wong was asymmetric with strong winds (scale 8 and up) in the front and to the right ofthe STS center.In the front,the radii of maximum velocities (RMV) remained around 60 km without much change,and the maximum wind band was about 50 km wide.To the right of the STS center,the RMW were 80～120 km away from the center with an ascending trend while the STS was going northwards,and the maximum wind band was about 100 km wide.The RWV showed few vertical differences both in the front and to the right of the STS center.The TREC winds were strongest at the altitude of lkm in the front,and decreased with height above it;on the right side,wind speeds showed little vertical variation between 1～3 km,much smaller compared to that in the front.The TREC winds and gradient observations from the tower on the Hill Liangmaoshan show that several wind speed maxima existed at around 159 m and 2～4 km.A constant flux layer height of Fung Wong was about 159 m.Within the constant flux layer,the wind profile followed the logarithm law.When the tower was in the front right side of the STS center,the gust coefficients decreased with altitude;while the tower was near or at the right rear of the center,the gust coefficients increased obviously with height and the vertical differences decreased.Above the constant flux layer,at 159～318 m,the wind profile did not follow the logarithm law and the gust coefficients showed little differences with height.
国家科技期刊平台
NSTL
万方数据
维普
