北京上空冬季潮汐波活动特征全天时激光雷达探测研究

Daytime Sodium Lidar Observations and Studies of the Tidal Characteristics in Winter over Beijing

利用北京延庆子午工程激光雷达对北京上空钠层进行长期连续观测,分析研究钠层及其相关参数的周日变化.提取钠层各个高度上的相位信息,与同时段经向风潮汐信息进行比较发现:在各个高度上,二者周日相位数值基本一致.半日相位对比结果表明,虽然存在差异,但整体仍保持较好的一致性.此外,从2014年至2016年每年10月到第二年1月共4个月的钠层连续观测数据中提取钠层周日和半日的振幅和相位,探究北京上空冬季的潮汐特征.结果显示:周日潮的相位自上向下传播,且无明显的季节变化特征,其垂直波长在40~50 km的范围;周日潮较强,半日潮较弱.

Based on continuous observation of the sodium layer from lidar located in Yanqing,Beijing,the diurnal variation of the sodium layer and its relevant parameters can be analyzed.Comparing the phase information of sodium density from every altitude with the information from meridian wind at the same time,it can be found that the two diurnal phases are consistent with each other.Although the two semi-diurnal phases exist a little bit difference,as a whole,they two agree very well.Extracting the phase and amplitude from continuous sodium observation data from October to January from 2014 to 2016,tidal characters in fall over Beijing can be studied.The results show diurnal tide phases have unobvious seasonal variation and propagate upward with vertical wavelengths between 30 and 50 km.Besides,the diurnal tide is stronger than the semidiurnal tide.