茫崖地区大风前近地层气温和风变化的特征分析

利用2006～2019 年茫崖观测站的高空探测资料,对该地区大风出现前的近地层气温和风的特征进行个例分析。结果表明:茫崖地区冬春季大风天气前由于强烈的地面逆温层,造成近地层动量堆积,而逆温层下面风速较小,甚至是静风;从近地风向变化看大风出现前08时一定出现放球后短时间内直接“过顶”的现象,垂直风速变化时低空风各层均与地面风速差较大,在规定高度与地面的风切变指数均大于1.0;大风前08时500hPa至地面的温度递减率最大,且湿度为整层最高,在埃玛图上多呈现下湿上干的为喇叭口形状。

Analysis on the characteristics of surface temperature and wind variation before gale in Mangya area

241/5000 Based on the high altitude data of Mangya observatory from 2006 to 2019, the characteristics of surface temperature and wind before the occurrence of gale in this region are analyzed. The results show that the momentum accumulation in the surface layer is caused by the strong ground inversion layer before the gale in winter and spring in the Mangya area, while the wind speed below the inversion layer is low or even quiet. According to the change of wind direction near the ground, there must be a direct "over the top" phenomenon in a short time after the ball was released when the wind appeared before 08. When the vertical wind speed changed, there was a big difference between the wind speed at all layers of low wind and the wind speed at the ground, and the wind shear index at the specified height and the ground was greater than 1.0. Before the high wind, the temperature drop rate from 500hPa to the ground is the largest, and the humidity is the highest in the whole layer. On Ematu, the lower wet and the upper dry are the shape of bell mouth