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，旨在利用理论、观测和大气化学模型相结合的方法来研究中间层上层和热层下层(MLT)的垂直输送机制。这项研究集中在80-105公里高度的中层顶区，并使用了来自智利塞罗帕雄和科罗拉多州桌山的两个观测点的Na和Fe风/温度激光雷达、流星雷达和气辉数据。其目的是量化在这些地点以上的中层顶区由波引起的垂直输送，描述其对热量、Na、Fe、O和其他关键组分的通量和垂直分布的影响，并将测量结果与传统上用来解释大气化学模式中垂直输送的涡旋扩散参数化方案进行比较。具体的科学目标包括：1)描述整个中层顶区和全年的热量、Na(在Cerro Pachon)和Fe(在桌山)的垂直通量，2)确定与平流、湍流混合、动力输送和Na/Fe化学有关的有效垂直输送速度，并描述它们的季节变化，3)通过比较模式预测和观测来量化波浪诱导输送对中层Na和Fe层结构和季节变化的影响，4)表征与OH Meinel带有关的有效垂直输送，O(1s)绿线和O2大气波段全年气辉排放；5)通过模式计算，评估波浪引起的输送对原子O等其他重要中间层成分的结构和变化的影响。智力优点：了解波浪引起的垂直输送的大小和变异性对于广泛的研究问题非常重要，包括大气环流模拟、大气化学模拟、热平衡计算以及对中间层气辉和金属层的研究。这项工作将有助于更深入地了解重力波的关键传输过程及其与大气化学的关系。此外，这项工作将显著提高我们模拟MLT的组成结构的能力，特别是流星金属层和气辉层。更广泛的影响：这项研究对大气科学有更广泛的影响，因为研究结果可以用来表征波浪诱导的输送对其他大气区域的其他重要成分的影响，例如平流层臭氧，这反过来又会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模拟中具有重要的应用。此外，直接测量中层Fe和Na的垂直通量，结合建模，将大大改进目前对高度不确定的全球大气输入通量绝对值的估计。这一点很重要，因为进入MLT的陨石碎片最终被输送到较低的大气层，在那里它影响平流层气溶胶的形成，并最终沉积在海洋中，在那里它有助于铁等关键化学物种的浓度。平流层气溶胶和海洋铁在地球气候中都扮演着重要的角色。平流层气溶胶反射阳光，这改变了地球的辐射收支，而海洋中的铁促进了浮游植物的生长，这影响了全球碳循环，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.