CEDAR: The Role of Gravity Waves in Coupling Longitudinal Variations in the Troposphere to the Thermosphere and Ionosphere

这是一项数据分析和建模工作，作为大气区域耦合、能量学和动力学项目的一部分。大气波是能量和动量可以在大气层的不同层之间传递的一种方式。最近的研究结果表明，大气中非迁移潮汐波的来源——与陆海对比相关的对流层中深细胞对流区的不均匀分布——也会引起大气重力波的变化来源。这项工作的主要目标是量化这一来源及其潜在影响，这是目前高层大气和电离层模型中缺失的，可能会迫使我们对电离层的明显潮汐特征是如何由大气中的波浪驱动的理解进行修订。卫星观测的全球温度和风数据集以及几个先进的全球大气和电离层环流模式将用于确定大尺度重力波的空间、时间和光谱特征，它们对潮汐变化的全球影响以及电离层的影响。重力波是中层-低层热层（MLT）动力学的一个重要强迫源，其影响强烈地影响着大气环流和气候模式。此外，数值天气预报模式虽然以对流层为重点，但已被证明，当高层大气动力学模型更精确时，它能做出更好的预测。这项工作将主要由一名博士后学者和一名研究生完成，他们都由首席研究员（PI）指导，并与伯克利和NCAR的数据分析和建模专家合作。

This is a data analysis and modeling effort to be undertaken as part of the Coupling, Energetics and Dynamics of Atmospheric Regions program. Atmospheric waves are one means by which energy and momentum can be transported between different layers of the atmosphere. Recent results show that the source of non-migrating tidal waves in the atmosphere -- the uneven distribution of deep cell convection zones in the troposphere associated with the land-sea contrast -- also gives rise to a varying source of atmospheric gravity waves. The main goal of this effort is to quantify this source and its potential effects, which is currently missing from models of the upper atmosphere and ionosphere and may force a revision in our understanding of how the apparent tidal signature in the ionosphere is driven by waves in the atmosphere. Global datasets of temperature and wind from satellite observations together with several advanced global atmospheric and ionospheric circulation models will be used to determine the spatial, temporal and spectral characteristics of large-scale gravity waves, their global effects on tidal variation, and the ionospheric impacts. Gravity waves are a significant forcing source on Mesosphere-Lower Thermosphere (MLT) dynamics and their effects strongly impact general circulation and climate models. In addition, numerical weather prediction models, despite their tropospheric focus, have been shown to make better predictions when the upper-atmospheric dynamics are more accurately modeled. The work will be performed mainly by a post-doctoral scholar and a graduate student, both mentored by the principal investigator (PI), and in collaboration with data-analysis and modeling experts at Berkeley and at NCAR.