Gravity Wave Interactions in the Global Atmosphere (GWING)

重力内波连接着对流层到热层的不同大气层，驱动着中层大气的大尺度环流。然而，许多过程从他们的产生，通过传播到耗散仍然没有完全理解，由于他们的小（往往是次网格）的长度尺度，他们在数值天气预报和气候模式中表现不佳。GWING是MS-GWaves研究单位的项目之一，旨在推进我们对上述涉及大气GW的多尺度动力学过程的理解，最终目标是开发从源到耗散的次网格尺度GW过程（及其影响）的统一参数化。为促进这一点，GWING项目的中心目标是开发和应用UA-ICON大气环流模式。通过UA-ICON，GWING项目正在整合整个MS-GWaves单元产生的新知识。在GWING的第二阶段，我们将集中在以下首要的科学问题：a）在经典的参数化，即水平传播，非瞬时传播，和波的瞬变平均流相互作用被忽略的GW功能的相关性是什么？B）重力波的全球大气环流及其变化的作用是什么？为了回答这些问题，我们将在全球范围内使用UA-ICON，包括GW允许的分辨率和粗分辨率，但使用最先进的WKB GW参数化（MS-GWaM）。此外，我们将继续模拟和分析具有局部高分辨率、GW分辨率嵌套的事件。模型模拟将与伙伴项目的观测知识相结合。因此，GWING第2阶段的主要UA-ICON开发目标是实施MS-GWaM（在合作伙伴项目3DMSD中开发），实施基于物理的源（与合作伙伴项目SV和3DMSD联合），以及在高模式分辨率下改进GWs的处理。使用UA-ICON的不同配置将最终允许评估迄今为止被忽视的功能的重要性，即回答我们的第一个首要问题。GWING的一个具体目标是对SSW期间的情况进行评估，SSW为GWs提供快速变化和区域不均匀的传播条件，因此可能特别容易受到非瞬时传播和波瞬变-平均流相互作用的影响。关于第二个首要问题，全球Ws对全球大气环流的作用，除了SSW，我们将集中在a）全球Ws和模式扩展到高层大气的全球变暖下的环流变化的作用，和B）全球Ws的天气预报技能的作用。

Internal gravity waves (GWs) link different layers of the atmosphere from the troposphere to the thermosphere and drive the large-scale circulation of the middle atmosphere. However, many of the processes from their generation via propagation to dissipation are still incompletely understood and due to their small (often sub-grid) length scale they are poorly represented in numerical weather prediction and climate models. GWING is one of the projects of the research unit MS-GWaves that aims at advancing our understanding of the above mentioned multiscale dynamical processes involving atmospheric GWs with the ultimate goal to develop a unified parameterization of sub-grid scale GW processes (and their effects) from the sources to the dissipation. To contribute to this, the central goal of the project GWING is the development and application of the UA-ICON atmospheric general circulation model. With UA-ICON, the GWING project is integrating the new knowledge generated by the whole MS-GWaves unit. In the 2nd phase of GWING we will focus on the following overarching scientific questions:a) What is the relevance of GW features neglected in classical parameterizations, i.e. horizontal propagation, non-instantaneous propagation, and wave transience-mean flow interactions.b) What is the role of gravity waves for the global atmospheric circulation and its variability?To answer these questions, we will use UA-ICON globally at both GW-permitting resolution and coarse resolution but with a state-of-the-art WKB GW-parameterization (MS-GWaM). Furthermore, we will continue to simulate and analyse episodes with locally highly resolved, GW-resolving nests. The model simulations will be combined with the observational knowledge from the partner projects. The major UA-ICON development goals in phase 2 of GWING are therefore the implementation of MS-GWaM (developed in partner project 3DMSD), the implementation of physics-based sources (jointly with partner projects SV and 3DMSD), and the improved treatment of GWs at high model resolutions. Using the different configurations of UA-ICON will finally allow to assess the importance of so far neglected features, i.e. to answer our first overarching question. A specific objective for GWING is this assessment for the situation during SSWs which provide rapidly changing and zonally inhomogeneous propagation conditions for GWs, and therefore may be particularly prone to effects of non-instantaneous propagation and wave transience-mean flow interactions. With respect to the 2nd overarching question, the role of GWs for the global atmospheric circulation, besides SSWs, we will focus on a) the role of GWs and model extension to the upper atmosphere for circulation changes under global warming, and b) the role of GWs for weather forecasting skill.