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利用2011~2013年期间60 h的钠荧光多普勒激光雷达温度和风场数据,采用矢端曲线法提取廊坊上空85~95 km中层顶区域准单色惯性重力波的所有参量,并统计准单色大气重力波的活动特性.获得的85次准单色重力波事件中,上传(下传)重力波64次(21次),占总数的75.29%(24.71%).垂直波长(水平波长)和观测周期平均值分别为6.6 km(727.8 km)和7.4 h,分别集中在6~9 km(200~800 km)和2~7 h,固有周期平均值为7.76 h,主要集中在3~9 h,水平传播方向分布比较均匀,没有占主导的传播方向.对于上传重力波,水平背景风在大气重力波水平传播方向上的分量取正值和取负值的概率大致相等,但对于下传重力波,该风场分量取正值的概率大约是取负值的2倍,说明观测到的下传大气重力波在中层顶区域多为顺风传播.“,”The quasi-monochromatic gravity waves (QM GWs)parameters in the mesopause region over Langfang (39.4° N, 116.6° E) were studied based on the 60 h sodium fluorescence Doppler lidar data during 2011-2013 year. A total of 85 QM GWs were extracted from the simultaneously measured temperature and wind profiles between 85 km and 95 km using hodograph method. The result shows that vertical wavelengths ( horizontal wavelengths ) and observed periods are mainly distributed from 6 km to 9 km (200 km to 800 km) and 2 h to 7 h, with the mean values 6.6 km (727.8 km) and 7.4 h respectively. GWs propagating upward in the vertical direction are with an occurrence of 75.29%. The intrinsic periods are mainly distributed from 3 h to 9 h with a mean value 7.76 h. There is no dominant horizontal propagation direction. The probability of the horizontal background wind component along the horizontal propagate direction Up>0 is about 50% for upward GWs, but for downward GWs the probability of Up>0 is about 66.66%, which is about 2 times of the probability of Up<0 (33.33%),which suggests that the observed downward GWs are mainly propagating horizontally along the wind.