2009年11月汕尾红海湾海面风场的观测分析

AN OBSERVATIONAL STUDY OF SEA SURFACE WIND FIELD AT RED BAY,SHANWEI IN NOVEMBER,2009

广州亚运会帆船帆板的比赛项目于2010年11月在汕尾红海湾广东省水上运动基地举行。根据2009年11月海上浮标观测数据,分析了红海湾赛场的海面风场特征及日变化规律;并根据地面气压场特点和风场日变化特征对海面风场进行了分类;最后,结合海-陆气压差观测数据,初步探讨海陆热力差异与海面风日变化的关系。结果表明:11月红海湾赛场以偏北和偏东风为主,风向具有近似余弦函数的日变化特征;风速的日变化不明显,但午后14—18时弱风和强风的出现机会较少,最适合比赛。11月红海湾赛场的海面风可归纳为海陆型、系统转折型和阴天型三种类型,三种类型的海面风分别占月总日数的46.7%、33.3%和20%。浮标-海丰观测站的气压差与海面风南北分量的变化有密切关系,可作为海面风场的有效预报指标。

The sailing events of the 16th Asian Games Guangzhou 2010 will be held at the Guangdong Ocean Sports Training Centre, Red Bay, Shanwei in November 2010. Based on the buoy observation data in November 2009, the characteristics of wind field and its diurnal variation are examined. Combined with the pressure difference between sea and land, an indicator for surface wind forecasting is sought. The results showed that in November the prevailing winds over the venue of Red Bay are northerly and easterly winds and the average wind speed can reach 6.8m/s or so; the sea surface wind field at night is mainly associated with northerly winds, the easterly wind is prevailing during the day, the diurnal variation of wind direction is similar to the variation of cosine function. Wind speed does not show a significant diurnal variation, but in the afternoon between 1400--1800 LST it has fewer opporttmities for weak or strong winds, which is the most suitable time for the contest. In November the surface wind at the venue can be divided into sea-land-, systematic turn- and cloudy-type, the percentages for the three types of wind field are 46.7%, 33.3% and 20%, respectively. The pressure difference between the buoy and Haifeng observation site has close relationship with the north-south component of the wind. It could be used as an effective forecasting indicator for the wind field.