浙江沿海通航环境风场要素气候变化特征分析

Wind Field's Climate Change of Zhejiang Costal Area Navigation Environment

选取1955~2007年浙江沿海不同纬度站点数据统计分析了浙江沿海通航环境的气候变化特征。统计分析表明:浙江沿海年平均风速呈下降趋势,气候倾向率达到-1.4^-4.2 m.s-1/10年,70年代年平均风速发生气候突变,7月和8月月平均风速变化波动最明显;年最大风速由北往南年下降趋势逐渐不明显,到南部玉环站则呈现微弱的增加趋势;沿海月最大风速的方向有比较明显的季节性;极大风速超过7级、8级和10级的年累计天数呈明显下降趋势。

Using the yearly wind field data observed by Zhejiang costal weather stations from 1955 to 2007,the characteristics of the wind field＇s climate change of Zhejiang coastal area navigation environment was analyzed.The results showed that annually averaged wind speed have tend to decrease and had the sudden change in 1970s.The yearly averaged wind speed variation tendency reached-1.6～-4.2 m/s 10a.The monthly averaged wind speed had the most distinctly variation during July and August.The decreasing tendency of maximum wind speed varied from north to south.The stations in north had the obvious decreasing tendency,but the Yuhuan station（in south） had the lower increasing tendency.The monthly averaged maximum wind speed had visible seasonal variation.The annually total days of extreme wind force over 7,8 and 10（on Beaufort scale） had the tend to decrease.