基于子午工程海南师范大学双波长(532nm、589nm)激光雷达、海南富克台站气辉仪和流星雷达对海南上空大气活动的长期观测,本项目拟采用双波长激光雷达数据拼接方法完成中层大气(35-85 km)温度结构反演,开展海南岛中高层大气温度季节变化以及重力波活动的观测研究工作。对照模式以及SABER卫星的观测结果，揭示近赤道、濒海地区中层大气温度季节变化的区域特性，研究海南上空逆温层现象。分析激光雷达对温度垂直结构的探测结果，采用小波方法分析重力波引起的大气温度扰动，提取重力波的垂直参数；利用气辉仪和流星雷达的同时观测，得到重力波在中层顶附近的水平参数以及背景风场信息；研究平流层到中层顶高度范围中的重力波传播过程，以及重力波饱和和耗散对中高层大气的影响，揭示重力波活动与中层大气异常温度结构的相关性；拓宽人们对低纬度大气动力学过程以及气候学的认知，服务于空间天气预报和相关模型的建立。

Based on the long-term observations of atmospheric activities from lidar, airglow imager, and meteor radar, atmospheric temperature structures and gravity wave activities in the middle and upper atmosphere over Hainan (19.5°N, 109.1°E) will be studied in this proposal project. Lidar at Hainan Normal University, airglow imager and meteor radar at Fuke belong to the Chinese Meridian Project. Observations and researches of the middle and upper atmosphere, basing on the three instruments, are partially supported by the Project Supported by the Specialized Research Fund for State Key Laboratories..Hainan lidar is a dual-wavelength lidar (@532nm, @589nm), and the atmospheric temperature structure in the altitude range of 35-85 km can be measured by combining lidar signals from the Rayleigh scattering channel (532 nm) and the sodium resonance fluorescence channel (589 nm). To reveal the seasonal variation characteristics of atmospheric temperature over Hainan Island, lidar-observed results would be firstly contrasted to those from SABER/TIMED satellite and model NRLMSISE-00. And then, lidar-observed phenomena of Mesosphere inversion layer (MIL) will be statistically investigated, and their formation mechanism will be discussed in detail..For the study of AGW activities in this proposal, lidar-observed vertical temperature perturbations will be analyzed in wavelet analysis method. Gravity wave parameters such as vertical wavelength, period and phase velocity will be extracted. Simultaneous observations from airglow imager at Fuke will be analyzed to obtain the horizontal wavelength, phase velocity and propagation direction of AGWs observed in the mesopause region. Background wind information will be measured by meteor radar at Fuke, and the wind perturbations will be used to extract the intrinsic period and propagation directions of AGWs..According to the simultaneous observations from three instruments above, gravity wave propagations from the stratosphere into the upper mesosphere (35-105 km) will be investigated comprehensively, as well the effects of the wave saturation, dissipation and breaking. And the correlations between AGW activities and those lidar-observed abnormal temperature structures will be studied in this proposed project. .Hainan Island is near the equator and mainly controlled by the tropics marine climate. These works in our proposal can enhance the understanding of the atmospheric dynamics and climatology in lower latitude area. And they could be helpful for the clarification of AGW contributions to atmospheric dynamics in the middle and upper atmosphere. They are also helpful to the space weather forecasting and the establishment of global climate parameterization model.