成都市温江边界层风场特征的研究

着眼于成都地区污染气象特征,利用温江2004年~2012年的地面观测资料及同期的探空资料,对该地区风场的统计特征进行了分析。结果表明:(1)从风频而言,温江地面风春、夏、秋3季均以偏北风为主,冬季则以东北风为主,因此,全年的主导风为偏北风。(2)从风速而言,区域静风和小风频率较高,占全年的68.7%;近10年来,温江年和4季的平均风速均呈现出减小趋势。(3)基于修正的帕斯奎尔稳定度分级法,利用幂指数律公式拟合了风随高度的变化,发现风廓线指数比国标值偏高,并随稳定度的增加而增大。(4)风速、稳定度联合频率的大值区主要出现在风速小于3m/s、稳定度为D~E类。上述研究成果对区域大气环境规划和工程治理具有重要的参考价值。

Study on the Characteristics of Wenjiang Boundary Layer Wind Field in Chengdu

Focusing on the air pollution characteristics in Chengdu,this study analyzed statistical characteristics of wind field in Chengdu using the ground observation data and the sounding data from 2004 to 2012 of Wenjiang area.The results showed that,（1） for wind frequency,the prevailing wind direction of Wenjiang in spring,summer and autumn was northerly wind,and in winter was northeasterly wind.Thus,the prevailing wind of the year was northerly wind.（2） for wind speed,the frequency of calm and light wind in the region was high,accounting for 68.7% of the year.During last decade,the mean wind speed of the year and four seasons in Wenjiang showed a obviously decreasing trend.（3） Based on the modified Pasquill stability classification method,using the power law equation,the changes of wind with altitude was fitted.Found out that the wind profile exponent was higher than the standard value,and increased with the atmospheric stability.（4） The high joint frequency of wind speed and stability mainly appeard in the wind speed under 3m /s and the stability was D ～ E.Above research results have important reference value for reginal atmospheric environmental planning and engineering management.