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

大气重力波（AGW）是中间层动力学和热平衡的主要贡献者。 这项研究有几个目标，将解决定量测量AGW及其在中间层和低热层的特征的需要。 研究结果将有助于加深对AGW动力学的理解，并有助于全球环流模式更准确地模拟全球气候变化。 将使用OH成像仪、多通道光度计和流星雷达进行测量。 该仪器目前位于夏威夷毛伊岛，并将重新安置在智利Cerro Tololo附近的南美场地（30 S，71 W）。 这些仪器将与伊利诺伊大学的Na激光雷达共同定位，该激光雷达将提供同一地区的高分辨率温度和风。 科学目标是：（1）利用OH气辉图像测量和研究具有大垂直波长的AGW携带的水平动量的垂直通量，这些AGW携带中间层中的波动量通量的主要部分。 流星雷达将提供风的测量数据，用于对观测到的相速度进行多普勒校正。 激光雷达观察到较慢速度的AGW，补充了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。 将与来自其他地理位置的类似测量以及来自犹他州州立大学中层温度成像仪的强度和温度扰动进行比较;（2）测量和研究短水平尺度AGW的垂直传播方向，并确定导管波在气辉观测中的重要性。 向上传播的动量可以被向下传播的波抵消，并且几项研究已经发现表明管道对于短水平波长可能是重要的条件。 本研究将统计量化向上/向下传播的发生概率，以及气辉中观察到的波的管道。 这项研究的数据将来自对OH分子的高时间分辨率的光度计测量，OH分子集中在86公里附近的一层，O2大气带集中在94公里附近;（3）了解气辉图像中观察到的大振幅事件，包括“壁波”。 虽然这些事件是罕见的，但它们可能对大气产生重大影响，仪器套件将提供对南美现场这些戏剧性事件的地球物理见解。 该项目更广泛的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。 该项目将支持一名研究生，其研究将包括理学硕士论文项目。 本科生将通过参与独立研究项目参与研究。 结果的出版物和介绍将在整个计划中进行。

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.