EAGER: Exploratory Measurements of Large Winds and Shears in the Lower Thermosphere and Their Variability Using an Enhanced Sodium Lidar

EAGER：使用增强型钠激光雷达探索性测量低层热层的大风和切变及其变化

• 批准号: 1954308
• 负责人: Tao Yuan
• 金额: $ 28.75万
• 依托单位: Utah State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-11-01 至 2022-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1954308&HistoricalAwards=false
• 关键词: EAGER; Exploratory; Measurements; Large; Winds

The upper atmosphere near 120 km in altitude is an important transitional region where the dominant mixing processes change from interaction of small swirls or eddies (eddy diffusion) to interaction of individual molecules (molecular diffusion). This is also the part of the upper atmosphere that is notoriously difficult to observe since traditional ground-based techniques such as lidar generally cannot measure above 100 km due to low signal power and since satellites orbit at higher altitudes to reduce atmospheric drag. Occasional rocket measurements revealed unexpected large vertical and horizontal neutral wind and shears in this region. These winds are believed to be critically important in formation of intense and thin layers of metallic ions as well as in formation of critical layers that control dissipation and vertical propagation of atmospheric waves connecting different atmospheric layers. This project will provide first comprehensive measurements of large horizontal and vertical wind by using a state-of-the-art sodium lidar system operated by the Utah State University (USU). The project will improve public literacy by the USU lidar observatory participating in public outreach events in the Utah Cache Valley rural community. This project will also provide training for one graduate student and one undergraduate student at USU. The project will involve (1) replacement of interference filters which will improve the quality of the wind measurement by reducing the associated uncertainties by a factor of 2, (2) exploratory measurements with the enhanced USU sodium lidar equipped with large aperture (~5 m^2 receiving area), and (3) analysis of temporal variations and duration of strong winds and shears in the lower thermospheric region between 100 and 120 km in altitude.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

海拔120 km接近120 km的上层大气是一个重要的过渡区域，在该区域中，主要的混合过程从小漩涡或涡流（涡流扩散）变为单个分子的相互作用（分子扩散）。这也是众所周知的上层大气的一部分，因为传统的地面技术（例如LiDAR）通常由于信号较低而无法测量100 km以上，并且由于较高高度的卫星轨道以减少大气阻力。偶尔的火箭测量结果显示出意外的大型垂直和水平中性风和该区域的剪切。人们认为，这些风对于形成金属离子的强和薄层以及在控制耗散和垂直传播的大气波的垂直层的临界层中至关重要。该项目将通过使用犹他州立大学（USU）运营的最先进的钠激光剂系统来首先全面测量大型水平和垂直风。该项目将提高USU LIDAR天文台参加犹他州Cache Valley农村社区公共外展活动的公共素养。该项目还将为USU的一名研究生和一名本科生提供培训。该项目将涉及（1）更换干扰过滤器，通过将相关的不确定性减少2倍，（（2）探索性测量值通过增强的USU钠激光剂，配备大量孔径（〜5 m^2接收区域），以及（3）较高的暂时性变化，（3）较高的持续时间分析，（3），（3）较高的持续时间分析，（3），探索性测量的质量将提高2，（2）探索性测量值，以及（3）较低的均值分析，并在（3）分析中的效率分析。该奖项反映了NSF的法定使命，并被认为是值得通过基金会的知识分子优点和更广泛影响的评论标准的评估来支持的。

项目成果

Evidence for Horizontal Blocking and Reflection of a Small‐Scale Gravity Wave in the Mesosphere

中间层小尺度重力波水平阻挡和反射的证据

• DOI: 10.1029/2019jd031828
• 发表时间: 2020
• 期刊: Journal of Geophysical Research: Atmospheres
• 作者: Criddle, N. R.;Pautet, P. ‐D.;Yuan, T.;Heale, C.;Snively, J.;Zhao, Y.;Taylor, M. J.
• 通讯作者: Taylor, M. J.

Temperature Tides Across the Mid‐Latitude Summer Turbopause Measured by a Sodium Lidar and MIGHTI/ICON

使用钠激光雷达和 MIGHTI/ICON 测量中纬度夏季涡轮顶温度潮汐

• DOI: 10.1029/2021jd035321
• 发表时间: 2021
• 期刊: Journal of Geophysical Research: Atmospheres
• 作者: Yuan, T.;Stevens, M. H.;Englert, C. R.;Immel, T. J.
• 通讯作者: Immel, T. J.

Temperatures in the Upper Mesosphere and Lower Thermosphere from O2 Atmospheric Band Emission Observed by ICON/MIGHTI

ICON/MIGHTI 观测到的 O2 大气带发射中上层中间层和下层热层的温度

• DOI: 10.1007/s11214-022-00935-x
• 发表时间: 2022
• 期刊: Space Science Reviews
• 影响因子: 10.3
• 作者: Stevens, M. H.;Englert, C. R.;Harlander, J. M.;Marr, K. D.;Harding, B. J.;Triplett, C. C.;Mlynczak, M. G.;Yuan, T.;Evans, J. S.;Mende, S. B.
• 通讯作者: Mende, S. B.