冬春季江苏沿海大风的特征

Weather Characteristics of Jiangsu Coast Gale in Winter and Spring

利用江苏2005—2006年460个自动站和加密站的风速资料,分析了2005—2006年冬春季发生的大风过程,研究发现冬春季沿海大风多由强冷空气引发,并具有一定的间断性、持续性、突发性和阵性特点,并对典型过程的阵性特征进行了分析。发现冷空气的入侵促使地面风场发展,大风u、v分量的变化与旋转系数具有很好的相关性,旋转系数的逐时波动与v分量的波动基本呈同位相变化趋势,而其与u分量的波动则有反位相关系;在冷空气影响前后,这样的相关特征始终维持。

Using the wind speed data of Jiangsu 460 automatic and intensive observation stations from 2005 to 2006,the high wind process of Jiangsu from winter 2005 to spring 2006 are analyzed, results show that the coastal gales in the winter and spring were induced by strong cold air intrusion, and had certain intermittence, duration and burst and gusty characters. Characteristics of a typical gust process from 2nd to 4th December 2005 are emphatically analyzed. It is found that the intrusion of cold surges promoted the development of ground wind, the changes of u, v components of gale were close correlated with rotation coefficient, i. e. Hourly rotation coefficient was positively correlated with v component variation and negatively correlated with u component variation;and such a correlation were maintained throughout around the cold air intrusion.