CEDAR: Numerical Investigation of Observed Multiscale Dynamics in the Middle Atmosphere

CEDAR：中层大气中观测到的多尺度动力学的数值研究

• 批准号: 1139155
• 负责人: Brian Laughman
• 金额: $ 24.4万
• 依托单位: NorthWest Research Associates, Incorporated
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1139155&HistoricalAwards=false
• 关键词: CEDAR; Numerical; Investigation; Observed; Multiscale

This is a 3-year modeling effort to be undertaken as part of the Coupling, Energetics and Dynamics of Atmospheric Regions program. Atmospheric gravity waves are believed to play a vital role in the transport of energy and momentum between atmospheric layers. This transport is enabled by the propagation of these waves vertically through the background atmosphere and dissipation of these occurs via the growth of instabilities (both convective and shear instabilities). This project utilizes two advanced numerical simulations to investigate gravity wave and instability processes in the Mesosphere-Lower Thermosphere (MLT) region. Previous simulations have been performed in idealized environments and small periodic domains. Here, the simulations will be extended to deep domain studies, which will examine these wave and instability processes in more realistic flows inspired by detailed observations.Gravity waves are a significant forcing source on 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. Specifically, improved understanding of when / where gravity waves become unstable in realistic flows that would result from this effort is a vital step towards improving parametrization of these waves in global-scale models.

这是一项为期 3 年的建模工作，作为大气区域耦合、能量和动力学计划的一部分。 大气重力波被认为在大气层之间的能量和动量传输中发挥着至关重要的作用。这种传输是通过这些波在背景大气中垂直传播而实现的，并且这些波的消散是通过不稳定性（对流不稳定性和剪切不稳定性）的增长而发生的。该项目利用两个先进的数值模拟来研究中层-低层热层（MLT）区域的重力波和不稳定过程。以前的模拟是在理想化环境和小周期域中进行的。在这里，模拟将扩展到深域研究，这些研究将在详细观测的启发下，在更真实的流动中检查这些波浪和不稳定过程。重力波是 MLT 动力学的重要强迫源，其影响强烈影响大气环流和气候模型。此外，尽管数值天气预报模型以对流层为重点，但当对高层大气动力学进行更准确的建模时，它已被证明可以做出更好的预测。 具体来说，通过这项工作，更好地了解重力波在现实流动中何时/何处变得不稳定，是改善全球尺度模型中这些波的参数化的重要一步。