CEDAR: Climatology and Characteristics of Instabilities and Atmospheric Gravity Waves at Low and Mid Latitudes

CEDAR：低纬度和中纬度地区不稳定性和大气重力波的气候学和特征

• 批准号: 0436516
• 负责人: James Hecht
• 金额: $ 24万
• 依托单位: Aerospace Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0436516&HistoricalAwards=false
• 关键词: CEDAR; Climatology; Characteristics; Instabilities; Atmospheric

Optical and near infrared imaging data from three sites are used to investigate the source and characteristics of gravity waves at low and mid-latitudes. Extant data from sites at the Maui MALT (Mesosphere and Lower Thermosphere) Atmospheric Observatory in Hawaii, at Adelaide Australia, and at Alice Springs Australia are analyzed, and new data are gathered. The imager at Maui Malt samples extremely bright OH Meinel emissions near 1600 nm, and is therefore capable of very fast sampling, achieving a signal-to-noise ration of 100 in one second. This imager is uniquely capable of capturing fast moving, short period gravity wave structures, and will be used to examine the possibility of a peak in gravity wave periods near the Brunt-Vaisala period (nominally five minutes), and the corresponding possibility of a sharp frequency cutoff for gravity wave periods shortward of this period. The Maui MALT imager data are also used to characterize the nature of small-scale instability features in the OH airglow layer. The relationship of these features to convectively unstable layers as well as the thickness of these layers is determined, and the morphology and climatology of these instabilities is characterized. The instruments in Australia are conventional optical imagers, separated by 1500 km. Data from these sites are used to examine a possible tropospheric convective source centered approximately 1300 km north of Alice Springs in Darwin. Due to the absence of orographic features between Alice Springs and Adelaide, the Australian imagers offer an excellent opportunity to isolate the role of tropospheric sources of MALT gravity waves.

利用三个站点的光学和近红外成像数据，研究了低、中纬度重力波的来源和特征。 对来自夏威夷、澳大利亚阿德莱德和澳大利亚爱丽丝泉的毛伊岛MALT（中间层和低热层）大气观测站的现有数据进行了分析，并收集了新的数据。 Maui Malt的成像仪在1600 nm附近对极亮的OH Meinel发射进行采样，因此能够非常快速地采样，在一秒钟内实现100的信噪比。 该成像仪是唯一能够捕捉快速移动，短周期的重力波结构，并将被用来检查在布伦特-维萨拉周期（标称5分钟）附近的重力波周期的峰值的可能性，以及相应的可能性的尖锐的频率截止的重力波周期shorthorough这一时期。 毛伊岛MALT成像仪的数据也被用来表征OH气辉层的小规模的不稳定性功能的性质。 这些功能的对流不稳定层以及这些层的厚度的关系被确定，这些不稳定的形态和气候的特点。 澳大利亚的仪器是传统的光学成像仪，相隔1500公里。 从这些网站的数据被用来检查一个可能的对流层对流源中心约1300公里以北的爱丽丝泉在达尔文。 由于爱丽丝泉和阿德莱德之间没有地形特征，澳大利亚成像仪提供了一个极好的机会来隔离对流层源的MALT重力波的作用。