CEDAR: Thermospheric Coupling with the Lower Atmosphere Using Lidar and CEDAR Instrument Cluster at Millstone Hill

该项目完成了Millstone Hill天文台瑞利-多普勒激光雷达系统的开发，并在现有仪器集群的一部分中运行。仪表群包括激光雷达系统、一个非相干散射雷达、一个法布里-珀罗干涉仪、一个流星风雷达和一个光学层析成像仪器。这些资料提高了对中层和低层热层过渡高度潮汐变率来源的认识。激光雷达仪器使用麻省理工学院林肯实验室Firepond 1.2米直径，完全可操纵的望远镜，因为望远镜的可操纵性允许在夜间进行高达86公里的全矢量风测量，并有可能在白天观察到较低的高度。仪器组以高分辨率测量密度、温度和风，大致覆盖30至130公里的整个高度范围，从而极大地将当前观测扩展到源区和重要的潮汐传播路径，在那里潮汐振幅被调制。白天和夜间同时收集的多普勒风和温度数据阐明了重力波（GW）耗散在潮汐结构变率中的作用。这些测量结果还检验了发展中的中间层温度逆温层与中下层纬向风急流的强迫之间的预期相关性，这两者都可能是由重力波耗散过程引起的。

This project completes development of a Rayleigh-Doppler lidar system at the Millstone Hill Observatory, and operates in part of an existing instrument cluster. The instrument cluster includes the lidar system, an incoherent scatter radar, a Fabry-Perot interferometer, a meteor wind radar, and an optical tomographic imaging instrument. The data improves understanding of sources of tidal variability in the altitude of transition between the mesosphere and lower thermosphere. The lidar instrument uses the MIT Lincoln Laboratory Firepond 1.2 meter diameter, fully-steerable telescope, as the telescope's steerability allows full vector wind measurements up to 86 km at night, with a potential for daytime observations to lower altitudes. The instrument cluster measures density, temperature, and winds with high resolution over roughly the entire altitude range from about 30 to 130 km, thus greatly extending current observations into the source region and into the important tidal propagation path, where the tidal amplitudes are modulated. Simultaneous Doppler wind and temperature data collected for both day and night clarifies the role that gravity wave (GW) dissipation has in contributing to the variability of tidal structure. These measurements are also examined for the expected correlation between the developing mesosphere temperature inversion layer and the forcing of the lower mesosphere zonal wind jet that may both be caused by gravity wave dissipation processes.