Collaborative Research: Observations and Analysis of Wave-Induced Constituent Transport in the Mesopause Region above Cerro Pachon, Chile and Table Mountain, Colorado

这是一项为期 5 年的科学合作，旨在结合理论、观测和大气化学模型来研究上层中间层和下层热层 (MLT) 的垂直输送机制。 该研究重点关注海拔 80-105 公里的中层顶区域，并采用来自智利塞罗帕雄和科罗拉多州桌山两个观测站的 Na 和 Fe 风/温度激光雷达、流星雷达和气辉数据。目标是量化这些站点上方中层顶区域中波引起的垂直输送，表征其对热量、Na、Fe、O 和其他关键成分的通量和垂直分布的影响，并将测量结果与涡流扩散参数化方案传统上用于解释大气化学模型中的垂直传输。具体的科学目标包括：1) 表征整个中层顶地区全年的热、钠（帕雄山）和铁（桌山）的垂直通量，2) 确定与平流、湍流混合、动力传递和钠/铁化学相关的有效垂直成分输送速度，并表征它们的季节变化，3) 量化波浪引起的输送对中层钠结构和季节变化的影响4) 表征与 OH Meinel 带、O(1S) 绿线和 O2 大气带气辉排放有关的有效垂直输运，以及 5) 通过模型计算评估波引起的输运对其他重要中层成分（如原子 O）的结构和变化的影响。 智力优点：了解波引起的垂直输运的幅度和变化对于广泛的研究非常重要一系列研究问题，包括大气环流建模、大气化学建模、热平衡计算以及中层气辉和金属层的研究。这项工作将有助于更深入地了解关键的重力波传输过程及其与大气化学的关系。此外，这项工作将显着增强我们对 MLT 组成结构进行建模的能力，特别是流星金属和气辉层。更广泛的影响：这项研究对大气科学具有更广泛的影响，因为研究结果可用于表征波浪引起的传输对其他大气区域其他重要成分（例如平流层臭氧）的影响，而平流层臭氧反过来又影响地球大气的热平衡。因此，该项目的结果可能在全球气候建模中具有重要的应用。此外，直接测量中层铁和钠的垂直通量，结合建模，将大大改善目前对全球大气输入通量绝对值的估计，而目前的估计是高度不确定的。这一点很重要，因为进入 MLT 的流星碎片最终会被输送到低层大气中，影响平流层气溶胶的形成，并最终沉积在海洋中，导致铁等关键化学物质的浓度增加。平流层气溶胶和海洋铁在地球气候中都发挥着重要作用。平流层气溶胶反射阳光，从而改变地球的辐射收支，而海洋铁则促进浮游植物的生长，从而影响全球碳循环，特别是大气中的二氧化碳。

This is a 5-year scientific collaboration to investigate vertical transport mechanisms in the upper mesosphere and lower thermosphere (MLT) using a combination of theory, observations, and atmospheric chemical models. The study focuses on the mesopause region, 80-105 km altitude, and employs Na and Fe wind/temperature lidar, meteor radar, and airglow data from two observation sites at Cerro Pachon, Chile, and Table Mountain, CO. The objectives are to quantify wave-induced vertical transport in the mesopause region above these sites, to characterize its effects on the fluxes and vertical distribution of heat, Na, Fe, O, and other key constituents, and to compare the measurements to the eddy diffusion parameterization schemes that are traditionally used to account for vertical transport in atmospheric chemistry models. Specific scientific goals include: 1) To characterize the vertical fluxes of heat, Na (at Cerro Pachon) and Fe (at Table Mountain) throughout the mesopause region and throughout the year, 2) To determine the effective vertical constituent transport velocities associated with advection, turbulent mixing, dynamical transport and Na/Fe chemistry and to characterize their seasonal variations, 3) To quantify the influence of wave-induced transport on the structure and seasonal variations of the mesospheric Na and Fe layers by comparing model predictions with observations, 4) To characterize the effective vertical transport associated with OH Meinel Band, O(1S) green line and O2 Atmospheric Band airglow emissions throughout the year at Cerro Pachon, and 5) Through model calculations to assess the influence of wave-induced transport on the structure and variations of other important mesospheric constituents such as atomic O. Intellectual Merit: Knowledge of the magnitude and variability of wave-induced vertical transport is important to a wide range of research problems, including general circulation modeling, atmospheric chemistry modeling, thermal balance calculations, and the study of the mesospheric airglow and metal layers. This work will contribute to a much deeper understanding of the key gravity wave transport processes and their relationships to atmospheric chemistry. In addition, this work will significantly enhance our ability to model the constituent structure of the MLT, particularly the meteoric metal and airglow layers. Broader Impacts: The research has broader implications for atmospheric science because the results can be used to characterize the impact of wave-induced transport on other important constituents in other atmospheric regions, such as stratospheric ozone, which in turn affects the thermal balance of the Earth's atmosphere. Hence, the results of this project may have important applications in global climate modeling. Furthermore, the direct measurements of the vertical fluxes of mesospheric Fe and Na, in combination with modeling, will substantially improve current estimates of the absolute value of the global meteoric input flux, which are highly uncertain. This is important because the meteoric debris that enters the MLT is eventually transported into the lower atmosphere, where it affects the formation of stratospheric aerosols and is ultimately deposited in the oceans, where it contributes to the concentration of key chemical species, such as Fe. Both stratospheric aerosols and oceanic Fe play important roles in Earth's climate. Stratospheric aerosols reflect sunlight, which alters the Earth's radiation budget, while oceanic Fe promotes the growth of phytoplankton, which affects the global carbon cycles, in particular atmospheric CO2.