浙江沿海台风阵风系数的影响因子分析  

ANALYSIS OF GUST FACTOR ASSOCIATED WITH TYPHOONS ON ZHEJIANG COAST

作　　者：胡波 HU Bo(Zhejiang Meteorological Observatory, Hangzhou 310017, China)

机构地区：[1]浙江省气象台,浙江杭州310017

出　　处：《热带气象学报》2017年第6期841-849,共9页Journal of Tropical Meteorology

基　　金：浙江省重大科技专项重点社会发展项目(2011C13044)资助

摘　　要：利用2004—2015年影响浙江海岛的台风及沿海气象站资料,分析台风阵风系数与平均风速、台风强度、测站高度、岛屿位置、台风与测站之间距离、台风象限和月份等因子的关系。结果表明,当平均风速较小时阵风系数的均值和波动幅度较大。在相同风速情况下,台风中心强度较强时的阵风系数会大些且其变化幅度随高度增大;而台风强度较弱时的阵风系数随高度变化不明显。最大阵风系数一般出现在台风与测站距离为150~250 km的区域内。台风第一和第四象限不仅其影响风力明显比第二和第三象限的强,且阵风系数变化幅度也较大。近海岸岛屿测站的阵风系数比远海岸岛屿测站要大。9月阵风系数波动范围比7—8月的小。从台风的自身环流来看,中低层的高度场、垂直速度场和湿度场等因子与阵风系数相关密切。Using the data of typhoons affecting Zhejiang coastal islands from 2004 to 2015 and corresponding wind of coastal meteorological stations, the relationships between the gust factor and mean wind speed, intensity of typhoons, height of stations, position of islands, distance between typhoons and stations, typhoons quadrants and months are analyzed. The results show that the fluctuation and mean value of gust factor are large when the average wind speed is small, and with the same wind speed, the gust factor is large when the typhoon is strong; when the typhoon is relatively weak, the gust factor changes little with height, but when the typhoon is strong, it varies by large amplitude; the maximum gust factor appears generally in the distance of 150~250 km between the typhoon center and stations, and in the first and fourth quadrant of the typhoon the wind is not only stronger than in the second and third quadrant, but also the variation range of wind gust factor is wider; the gust factor in island stations near the coast is significantly smaller, and in September the fluctuation range of gust factor is smaller than that of July and August. From the analysis of typhoon circulations, it is known that the geopotential height field, vertical velocity field and humidity field are closely related with the gust factor.

关 键 词：台风 阵风系数 因子 沿海 环流 

分 类 号：P425.2[天文地球—大气科学及气象学]