Multi-Scale Dynamics of Gravity Waves MS-GWaves (Coordination proposal)

只有由于正确的原因正确地模拟当前气候，才能获得对气候预测的信心。目前，对预报的布鲁尔-多布森环流增强、平流层对对流层的动力向下耦合、臭氧超恢复等动力学特征存在争论。在这种情况下，一个特别大的不确定性来源是内部重力波（GWs），它不能被当前的化学-气候模式所解决，而是由很大程度上过于简化的参数化来表示。研究单位（RU）将以物理和数学上一致的方式制定GW激发、传播和耗散的显式模型。这些将通过过程解析数值模拟和测量进行测试。将特别关注重力波与湍流、平衡流的多尺度相互作用，以及未解析的小尺度GWs与大尺度、已解析的GWs的多尺度相互作用。待开发的模式将导致从震源到耗散的gw统一参数化。GW参数化、全球GW许可和局部GW解析模型将用于量化和减轻GW对大气环流、大气大尺度动力过程和气候变化影响的不确定性。这项工作将基于数学、理论、高分辨率数值模拟、波浪过程本身及其在全球范围内影响的测量等密切的跨学科互动。之所以采用这种方法组合，是因为只有测量与现实有直接联系，只有理论才能理解，只有高分辨率的建模才能提供详细的诊断。这样一个全面的计划远远超出了单一研究机构或一些双边合作的可能性，而是需要多个研究所联合他们的实验，计算和理论能力。从RU获得的长期收益是：-加强和加深对大气中GWs的空间、时间和光谱分布的概述。-对导致和控制相应GW动态的过程的理解有了显著提高。-在此基础上，增加了作为亚电网尺度现象的GW参数化的鲁棒性和完整性，解决了源过程，GW传播，GW平均流相互作用和GW耗散。-因此，在异常条件下，例如气候变化，GW参数化的性能更可靠。

Confidence in climate prediction can only be gained if the present climate is modeled correctly for the correct reasons. Currently, there is a debate on dynamical features such as the predicted enhancement of the Brewer-Dobson circulation, the dynamical downward coupling of the stratosphere on the troposphere, and ozone super-recovery. A particularly large source of uncertainty in this context are internal gravity waves (GWs), which cannot be resolved by current chemistry-climate models and are represented by largely oversimplified parameterizations instead. The research unit (RU) will formulate explicit models of GW excitation, propagation, and dissipation in a physically and mathematically consistent way. These will be tested via process-resolving numerical modeling and measurements. Special attention will be given to multi-scale interactions of gravity waves with turbulence, with the balanced flow, and of unresolved small-scale GWs with large-scale, resolved GWs. Models to be developed will lead to a unified parameterization of GWs, from their sources to their dissipation. Both the GW parameterization and global GW permitting and local GW resolving modeling will be used to quantify and mitigate the uncertainties in the understanding of GW impacts on the atmospheric circulation, large-scale dynamical processes in the atmosphere, and climate change. The effort will be based on a close interdisciplinary interaction of mathematics, theory, high-resolution numerical modeling, and measurements of both the wave processes themselves and their effects on the global scale. This combination of methods is employed since only measurements hold the direct link to reality, only theory allows to understand, and since only high-resolution modeling can provide a detailed diagnosis. Such a comprehensive program is far beyond the possibility of a single research institute or some bilateral cooperation but requires a RU with various institutes joining their experimental, computational, and theoretical capabilities. The long-term gains from the RU are to be:- An enhanced and deepened overview of the spatial, temporal and spectral distribution of GWs in the atmosphere.- A significantly improved understanding of the processes causing and controlling the corresponding GW dynamics.- Based on this an increase in the robustness and completeness of the parameterization of GWs as subgrid-scale phenomenon, addressing source processes, GW propagation, GW mean-flow interaction, and GW dissipation.- Hence a more reliable performance of GW parameterizations under anomalous conditions, e.g. climate change.