CEDAR: Global Climatology of Mesospheric Inversion Layers

研究人员将利用卫星数据生成一个关于中间层逆温层的全球气候学。气候学将用于探索这些层的源机制，并确定它们对中层大气动力学的贡献。mil在中间层和低层热层中相当常见。它们的特征是相对于海拔65至75公里或85至95公里之间的温度升高。卫星观测表明，mil的寿命很长，可以延伸数万公里。地基和天基数据集表明，mil在低纬度和中纬度地区比在高纬度地区更为常见。对mil的兴趣是由它们对中层大气的能量学和组成的重要意义引起的：它们可以显著地改变重力波的传播环境和特征，从而影响平均流量和潮汐结构。由于mil似乎相当普遍，因此在制定一般环流模式的重力波参数化方案时可能必须考虑它们对重力波传播的影响。即将组装的气候学将实现几个目标：它将有助于建立尚不清楚的mil源机制；它将能够描绘潮汐和行星波对mil的贡献以及耗散波通量引起的平均状态的变化；它将提供在北纬高纬度地区很少见到的mil的信息。为了产生气候学，该项目将利用卫星（TIMED、NASA Aura和NIMBUS 7任务）和柯林斯堡、毛伊岛和阿雷西博的激光雷达的温度。来自犹他州贝尔湖的气辉图像也将被检查，以推断重力波的信息。研究活动的核心主题是低层大气与高层大气之间的动力耦合以及不同纬度之间的耦合。该项目由一名女科学家领导，将支持一名理工科学生的教育和培训。它还将促进气辉、激光雷达和卫星观测团队之间的合作活动。本文的研究结果有望：(1)阐明潮汐和瞬态波在MIL理论中的作用；(2)增加对北高纬度等稀疏观测地区MIL发生情况的认识；(3)指导从地面平台观测的mil和导管重力波的解释；(4)向中层大气模拟界通报重力波破碎参数化的潜在影响。

The investigators will generate a global climatology of mesosphere inversion layers (MILs) using satellite data. The climatology will be used to explore the source mechanisms for the layers and to establish their contributions to the dynamics of the middle atmosphere. MILs are fairly common occurrences in the mesosphere and lower thermosphere. Their signature is an increase in temperature with respect to altitude between 65 and 75 km or between 85 and 95 km. Satellite observations suggest that MILs can be long-lived and extend over tens of thousands of kilometers. Both ground-based and space-based datasets indicate that MILs are more common at low and middle latitudes than at high latitudes. The interest in MILs is sparked by their important implications for the energetics and composition of the middle atmosphere: they can significantly alter the propagation environment and the characteristics of gravity waves which in turn affects the mean flow and tidal structures. Since MILs appear to be fairly ubiquitous, their effects on gravity wave propagation may have to be considered in the formulation of gravity wave parameterization schemes for general circulation models. The climatology to be assembled will accomplish several goals: it will help establish the source mechanism for MILs which are not well understood; it will enable delineating the contributions of tides and planetary waves to the MILs as well as changes to the mean state caused by the fluxes of dissipating waves; and it will provide information on the MILs in a region where they have been rarely seen, the high northern latitudes. To produce the climatology, the project will utilize temperatures from satellites (the TIMED, NASA Aura, and the NIMBUS 7 missions) and from lidars at Fort Collins, Maui, and Arecibo. Airglow images from Bear Lake, Utah, will also be examined to infer information on gravity waves. The research activities address core CEDAR themes of dynamical coupling between the lower atmosphere and the upper atmosphere as well as coupling between different latitudes. The project is being led by a female scientist and will support the education and training of a science and engineering student. It will also promote collaborative activities between airglow, lidar, and satellite observing teams. The results of this investigation are expected to: (1) clarify the roles of tides and transient waves in MIL theory; (2) augment the knowledge of MIL occurrences in sparsely observed areas such as the high northern latitudes; (3) guide the interpretation of MILs and ducted gravity waves viewed from ground-based platforms; and (4) inform the middle atmosphere modeling community on potential impacts on gravity-wave breaking parameterizations.