CEDAR: Simultaneous Fe and Na Doppler Lidar Measurements of Heat and Constituent Fluxes in the Mesopause Region and Neutral Metal Layers, Winds and Temperatures in the Thermosphere

两台多普勒激光雷达，一台新开发的铁（Fe）多普勒激光雷达和一台现有的钠（Na）多普勒激光雷达将同时在科罗拉多州博尔德附近的Table Mountain运行，以获取中性大气水平和垂直风、温度以及中间层和热层中铁和钠密度的垂直剖面，以研究80至150公里之间的耦合和传输过程。热层金属层本身涉及离子层和中性金属层之间的耦合，而中性风和来自这些层的温度是推进我们对空间-大气相互作用区域理解所需的两个关键参数。中间层和热层的中性风和温度数据将有助于验证覆盖低层和高层大气的全球模式（例如，WACCM和WAM）。同时测量铁和钠层及其通量将提供有关热层金属层形成、不同的大气烧蚀和宇宙尘埃速度分布的重要信息。这项工作将导致对宇宙尘埃输入的定量估计的改进，这对整个极地大气和南大洋的各种地球物理过程都有影响。具体而言，双激光雷达观测，以及相关研究和模式模拟，将用于：(1)表征最近发现的Table Mountain上方热层Fe和Na层，以确定它们发生的频率，它们延伸的高度，持续的时间，以及它们形成的机制；(2)利用热层Fe和Na层作为示踪剂，表征了热层100-150 km区域的中性风和温度。通过与全大气模式（WAM）模拟的比较探讨耦合和输运过程；(3)同时测量中层顶区域（80 ~ 105 km）的波致垂直热通量和Fe和Na的动力学和化学通量，量化Fe和Na的差异大气烧蚀，约束各种宇宙尘埃速度分布模型，帮助验证英国利兹大学的化学烧蚀模型（CABMOD），显著改善对全球宇宙尘埃流入的估计。本项目将为一名博士后和一名研究生提供研究机会。

Two Doppler lidars, a newly developed iron (Fe) Doppler lidar and an existing sodium (Na) Doppler lidar will be operated simultaneously at Table Mountain near Boulder, CO, to acquire vertical profiles of neutral atmospheric horizontal and vertical winds, temperatures, and Fe and Na densities in the mesosphere and thermosphere to study coupling and transport processes between 80 and 150 km. The thermospheric metal layers themselves involve the coupling between ion and neutral metal layers, and the neutral winds and temperatures derived from these layers are two critical parameters needed for advancing our understanding of the space-atmosphere interaction region. The neutral wind and temperature data in the mesosphere and thermosphere will help validate global models that cover the lower and upper atmosphere (e.g., WACCM and WAM). The simultaneous measurements of Fe and Na layers and their fluxes will provide crucial information on the thermospheric metal layer formation, differential meteoric ablation, and cosmic dust velocity distribution. This work will lead to improvements in quantitative estimates of the cosmic dust input that has implications for a variety of geophysical processes throughout the polar atmosphere and Southern Ocean. Specifically, the dual lidar observations, along with correlative studies and model simulations, will be used to: (1) Characterize the recently discovered thermosphere Fe and Na layers above Table Mountain to determine how frequently they occur, how high they extend, how long they persist, and what mechanisms cause them to form; (2) Characterize neutral winds and temperatures in the 100-150 km region of the thermosphere by using the thermosphere Fe and Na layers as tracers. Explore coupling and transport processes via comparison with the Whole Atmosphere Model (WAM) simulations; and (3) Make simultaneous measurements of wave-induced vertical heat fluxes and the dynamical and chemical fluxes of Fe and Na in the mesopause region (80-105 km) to quantify the differential meteoric ablation of Fe and Na, constrain the various cosmic dust velocity distribution models, help validate the University of Leeds chemical ablation model (CABMOD) and significantly improve estimates of the global influx of cosmic dust. This project will provide research opportunities for a postdoc and a graduate student.