CEDAR: The Influence of Lower Atmosphere Forcing on the Composition Structure of the Thermosphere

为了量化低层大气对热层组成结构的向上耦合，研究人员在两个现有模型中使用了一个基于物理学的“无缝”全球模型。光谱中间层低层热层模式（SMLTM）对平均风、潮汐振幅和重力波强迫进行了真实的模拟，而耦合热层电离层模式（CTIM）研究了高层大气的物理特性，包括热层-电离层相互作用，以及对太阳和地磁活动的动力学和成分响应。结合起来，这两个模式强调了潮汐和重力波的季节和半球不对称性对大气主要物种组成的影响。此外，它们还确定低层大气强迫对热层组成、温度和风结构以及中性密度异常的影响。

In attempting to quantify the upward coupling of lower atmosphere forcing on the thermosphere's composition structure, the investigators are using a 'seamless' global model based on physics within two existing models. The Spectral Mesosphere Lower Thermosphere Model (SMLTM) produces realistic simulations of mean winds, tidal amplitudes, and gravity wave forcing, while the Coupled Thermosphere Ionosphere Model (CTIM) examines physics of the upper atmosphere, including thermosphere-ionosphere interactions, and the dynamics and composition response to solar and geomagnetic activity. Combined, the two models emphasize the impact seasonal and hemispheric asymmetry of tides and gravity waves have on major species composition of the atmosphere. In addition, they determine the impact of lower atmosphere forcing on thermospheric composition, temperature and wind structure, and neutral density anomalies.