斜压大气中海面边界层摩擦偏角的动力学研究  

DYNAMIC RESEARCH ON THE FRICTIONAL DEFLECTION ANGLE IN THE BAROCLINIC MARINE PLANETARY BOUNDARY LAYER

作　　者：王华[1] 徐银梓[2] 

机构地区：[1]南京大学中尺度灾害性天气教育部重点实验室,南京210093 [2]南京大学大气科学系,南京210093

出　　处：《气象科学》2002年第1期16-27,共12页Journal of the Meteorological Sciences

基　　金："南京大学中尺度灾害性天气教育部重点实验室"课题的资助

摘　　要：本文在 Ekman动量近似 [1] 下 ,引入关于水面粗糙度的 Charnock[2 ] 公式 ,求得了斜压大气中海面边界层的风速的解析表达式 ,进一步得到边界层摩擦偏角的公式 ,并获得了边界层摩擦偏角的有关结论。例如海面的摩擦偏角远小于陆地的摩擦偏角 ;低纬的摩擦偏角比高纬的要大 :理论分析和个例计算均表明 ,垂直平流惯性力与水平平流惯性力对摩擦偏角分别起着减小和增大的相反作用 ,而且反气旋性涡度处与气旋性涡度处的摩擦偏角可相差达 2 0多度。冷暖平流下的摩擦偏角相差很大 ,甚至可达七、八十度。By the Ekman momentum approximation [1]and introducing Charnock's formula [2]on the roughness over water,the expression of the wind distribution in the baroclinic marine planetary boundary layer is obtained in this paper,from which the formulas of the frictional deflection angle between the wind vector at the marine surface and the geostrophic wind at the top of the boundary layer are got.Some solutions are obtained,which are helpful to the forecast of the distribution of the wind in the marine baroclinic boundary layer. For example,the frictional deflection angle on land is greater than one on sea surface,which is only one-second or one-third of the former.Moreover,the diffrence between the frictional deflection angles in case of cold advection and warm advective is even reaching 70 to 80 degrees.The horizontal/vertical advective initial force causes the frictional deflection angle to increuse/decrease.The conclusions above play a direct role in forecasting of the frictional deflection angles in the baroclinic marine planetary boundary layer.

关 键 词：海面边界层 摩擦偏角 斜压性 风速 斜压大气 水面粗糙度 

分 类 号：P433.2[天文地球—大气科学及气象学]