上海地区沿海(江)岸非汛期不同重现期最大风速估算

Estimation of the Maximum Wind Speed in Different Return Periods in Shanghai Coastal Areas during Non-Flood Season

非汛期不同重现期最大风速是沿海(江)岸堤防设计标准、工程安全性和投资成本估算的一个重要参数。文中基于上海崇明、宝山、南汇、奉贤和金山5个沿海(江)岸气象站历史风速观测资料和横沙岛测风塔10 m高度逐日最大风速资料,采用极值I型分布估算了上海地区沿海(江)岸非汛期(1—5月和10—12月)各风向不同重现期最大风速。结果表明,上海地区沿海(江)岸非汛期的最大风速以W风最大,SW风最小。沿海(江)岸非汛期50 a一遇最大风速为23.3—28.3 m/s,小于上海地区基准风速(30.0 m/s)。各地非汛期不同风向50 a一遇最大风速的最大差值为3.4—8.1 m/s,同一重现期各地沿海(江)岸10 m高度最大风速极值也相差较大。崇明区域非汛期沿海(江)岸最大风速最大,其次是南汇区域,宝山区域最小。上海地区最大风速一般都出现在沿海地带,其分布与上海实际地理、地表状况相符。

The maximum wind speed of different recurrence periods is an important parameter in the design standards,engineering safety and investment cost estimation for coastal embankments during non-flood season.Based on the historical wind speed observation data of meteorological stations and daily maximum wind speed data at 10 m altitude of the anemometer tower of Hengsha Island in Shanghai during February 2009 to March 2010,the maximum wind speed of different recurrence periods was estimated in Shanghai coastal areas during non-flood season by using extreme value type I distribution.The results showed that the maximum wind speed during non-flood season was the largest in westerly wind direction and the smallest in southwest direction.Maximum wind speed of 50-year recurrence period was 23.3-28.3 m/s during non-flood season,which was less than the reference wind speed（30.0 m/s）recorded in ＂Architectural Structure Load Standards＂for Shanghai.The maximum difference among different wind directions was 3.4-8.1 m/s in Shanghai for the 50-year recurrence period during non-flood season,and the extreme values of maximum daily wind speed at 10 m altitude also showed great difference among the study areas during the same recurrence period.The wind speed in Chongming coastal areas was the maximum during non-flood season,followed by Nanhui,and the wind speed in Baoshan coastal areas was the minimum.The maximum wind speed generally appeared in the seaboard in Shanghai.The distribution of the maximum wind speed was in good agreement with the actual geography and surface conditions.