Gravity wave Ray tracing Parameterization and its Effects in Solar cycle modeling (GRAPES)

大气环流模拟的长期运行依赖于基于柱的重力波参数化，即假设重力波只垂直传播。然而，通过全球射线追踪实验，我们发现由于重力波的斜向传播，背景风的纬向平均加速度存在实质性差异。特别是，经向加速主要是由波的空间分离引起的，其中一部分波向北传播，一部分波向南传播（这在基于柱的参数化中不会发生），以及波将中纬度中间层起源从低纬度驱动到更大的部分。这些结果是基于离线研究，使用规定的背景大气和卫星观测调整的发射分布。我们现在建议在一个耦合GCM研究中研究这些影响。我们将在GROGRAT射线追踪器的基础上开发一种射线追踪重力波参数化方法。新方案的发射分布将以卫星、地面和现场观测为指导。然而，调整GCM将是必要的。参数化将集成到ROSE模型中，并进行不同太阳周期条件下的模拟。将比较纯垂直波传播和斜波传播的运行，以便量化斜波传播对不同太阳活动的大气响应的影响。

Long term runs of general circulation modeling rely on column-based gravity wave parameterizations, i.e. gravity waves are assumed to propagate only vertically. However, using global ray tracing experiments we showed that there are substantial differences in the zonal mean accelerations of the background wind due to oblique propagation of gravity waves. In particular, the meridional acceleration is primarily caused by the spatial separation of waves part of them propagating northward and part southward (which would not happen in a column-based parameterization) and waves driving the mid-latitude mesosphere origin to a larger fraction from lower latitudes. These results are based on offline studies using a prescribed background atmosphere and a launch distribution tuned by satellite observations. We propose now to investigate these effects in a coupled GCM study. We will develop a ray tracing gravity wave parameterization based on the GROGRAT ray tracer. The launch distribution of the new scheme will be guided by satellite, ground-based and in-situ observations. Tuning in the GCM will nevertheless be necessary. The parameterization will be integrated in the ROSE model and simulations for different solar cycle conditions will be performed. Runs with purely vertical and oblique wave propagation will be compared in order to quantify the effects of oblique wave propagation on the atmospheric response to different solar activity.