CEDAR: Mesospheric Dynamics with Airglow Imaging, Photometry and Meteor Radar

大气重力波(AGW)是中层大气动力学和热平衡的重要组成部分。这项研究有几个目标，将解决对中间层和较低热层中的AGW及其特征进行定量测量的必要性。研究结果将有助于加深对全球重力波动力学的理解，并有助于全球环流模式通过更好的重力波参数化来更准确地模拟全球气候变化。测量将使用OH成像仪、多通道光度计和流星雷达进行。该仪器目前位于HI的毛伊岛，并将搬迁到智利Cerro Tololo(30 S，71西)附近的南美地点。这些仪器将与伊利诺伊大学的激光雷达放在同一地点，后者将在同一地区提供高分辨率的温度和风。科学目标是：(1)使用OH气辉图像测量和研究具有大垂直波长的AGW携带的水平动量垂直通量，这些AGW携带中间层波动量通量的主要部分。流星雷达将提供风速测量，用于对观测到的相速度进行多普勒校正。激光雷达观测到速度较慢的AGW，它们补充了在气辉中观察到的光谱。通量的方向和大小以及它们随季节的变化将被表征。将与其他地理位置的类似测量以及犹他州立大学中层温度映射器的强度和温度摄动进行比较；(2)测量和研究水平短尺度AGW的垂直传播方向，并确定导管波在气辉观测中的意义。向上传播的动量可能被向下传播的波抵消，一些研究发现，对于较短的水平波长，导管可能是重要的条件。这项研究将对气辉中观察到的波的向上/向下传播和导管的发生概率进行统计量化。这项研究的数据将来自对集中在86公里附近的层中的OH分子和集中在94公里附近的O2大气波段的高时间分辨率光度计测量的数据；(3)了解在气辉图像中观察到的大幅度事件，包括“壁波”。尽管这些事件很少见，但它们可能会对大气产生重大影响，仪器套件将提供对南美地点这些戏剧性事件的地球物理洞察。该项目的更广泛影响包括与伊利诺伊大学、犹他州和航空航天公司的其他研究人员的合作。这个项目将支持一名研究生，他的研究将包括理科硕士论文项目。本科生将通过参与自主学习项目参与研究。结果的出版物和演示将贯穿整个计划。

Atmospheric Gravity Waves (AGWs) are a major contributor to the dynamics and thermal balance in the mesosphere. This study has several objectives which will address the need for quantitative measurements of AGWs and their signatures in the mesosphere and lower thermosphere. The results will improve understanding of AGW dynamics and help global circulation models to make more accurate simulation of the global climate change with better gravity wave parameterization. Measurements will be carried out using an OH imager, a multi-channel photometer, and a meteor radar. This instrumentation is currently located at Maui, HI and will be re-located to a South American site near Cerro Tololo, Chile (30 S, 71 W). These instruments will be co-located with the University of Illinois Na lidar which will provide high resolution temperature and wind in the same region. The science objectives are: (1) to use OH airglow imagery to measure and study the vertical flux of horizontal momentum carried by AGWs with large vertical wavelengths, which carry the major portion of the wave momentum flux in the mesosphere. The meteor radar will supply wind measurements to be used for Doppler correction of observed phase speeds. The lidar observes slower speed AGWs that complement the spectrum observed in airglow. The direction and magnitude of the fluxes, and their variation with season, will be characterized. Comparisons will be made to similar measurements from other geographic locations and with the intensity and temperature perturbations from the Utah State University Mesospheric Temperature Mapper; (2) to measure and study the vertical propagation direction of short-horizontal-scale AGWs, and to determine the significance of ducted waves in airglow observations. Upward propagating momentum may be cancelled by downward propagating waves, and several investigations have found conditions suggesting ducting may be significant for short horizontal wavelengths. This study will statistically quantify occurrence probabilities for upward/downward propagation, and ducting for waves observed in airglow. The data for this study will be from photometer measurements with high time resolution of the OH molecule which is concentrated in a layer near 86 km and of the O2 atmospheric band, concentrated near 94 km; (3) to understand the large amplitude events observed in airglow images, including "wall waves". Although these events are rare, they may have significant impacts on the atmosphere and the instrument suite will provide geophysical insight into these dramatic events over the South American site. The broader impacts of the project include collaborations with other investigators at the University of Illinois, Utah State, and the Aerospace Corporation. This project will support one graduate student, whose research will comprise the Master's of Science thesis project. Undergraduate students will be involved in the research through participation in independent study projects. Publications and presentations of results will be made throughout the program.