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

CEDAR：利用气辉成像、光度测量和流星雷达进行中层动力学

• 批准号: 0737656
• 负责人: Alan Liu
• 金额: $ 31.45万
• 依托单位: University of Illinois at Urbana-Champaign
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0737656&HistoricalAwards=false
• 关键词: CEDAR; Mesospheric; Dynamics; Airglow; Imaging

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.

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，将满足对 AGW 及其在中层和低层热层中的特征进行定量测量的需求。 研究结果将增进对AGW动力学的理解，并帮助全球环流模型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。 该仪器目前位于夏威夷州毛伊岛，并将搬迁至智利托洛洛山附近的南美地点（南纬 30 度，西经 71 度）。 这些仪器将与伊利诺伊大学 Na 激光雷达位于同一地点，后者将在同一地区提供高分辨率温度和风。 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携带了中间层中波动量通量的主要部分。 流星雷达将提供风测量数据，用于对观测到的相速度进行多普勒校正。 激光雷达观察到速度较慢的 AGW，这些 AGW 补充了在气辉中观察到的光谱。 通量的方向和大小及其随季节的变化将被表征。 将与其他地理位置的类似测量结果以及犹他州立大学中层温度测绘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，确定导管波在气辉观测中的意义。 向上传播的动量可能会被向下传播的波抵消，并且一些研究发现，表明波导对于短水平波长可能很重要。 这项研究将统计量化向上/向下传播的发生概率，以及在气辉中观察到的波的传导。 这项研究的数据将来自光度计的高时间分辨率测量，对 OH 分子（集中在 86 km 附近的层）和 O2 大气带（集中在 94 km 附近）进行测量； （3）了解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，但它们可能对大气产生重大影响，仪器套件将为南美地区这些戏剧性事件提供地球物理洞察。 该项目更广泛的影响包括与伊利诺伊大学、犹他州立大学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来参与研究。 结果的出版物和演示将在整个计划期间进行。