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.

在120公里高度附近的高层大气是一个重要的过渡区域，在那里主要的混合过程从小涡旋或涡旋的相互作用（涡旋扩散）转变为单个分子的相互作用（分子扩散）。这也是众所周知的难以观测的高层大气的一部分，因为传统的地面技术，如激光雷达，由于信号功率低，通常无法测量100公里以上，而且卫星在更高的高度轨道上运行，以减少大气阻力。偶尔的火箭测量显示，在这一地区意想不到的大垂直和水平中性风和切变。这些风被认为在形成金属离子的密集和薄层以及形成控制连接不同大气层的大气波的耗散和垂直传播的关键层方面至关重要。该项目将通过使用由犹他州州立大学（USU）运营的最先进的钠激光雷达系统，首次全面测量大型水平和垂直风。该项目将通过USU激光雷达观测站参与犹他州Cache Valley农村社区的公共宣传活动来提高公众的识字率。该项目还将为南加州大学的一名研究生和一名本科生提供培训。该项目将涉及（1）更换干涉滤光片，通过将相关的不确定性降低两倍来改善风测量的质量，（2）使用配备大孔径的增强型南加州大学钠激光雷达进行探索性测量（~5 m^2接收面积），以及（3）在100和120 km高度之间的低热层区域强风和切变的时间变化和持续时间的分析。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

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.