标题： 非经典重力波动力学对中间大气平均流和太阳潮汐的影响 显示英文标题

标题： Impact of Non-Classical Gravity-Wave Dynamics on Middle-Atmosphere Mean Flow and Solar Tides

摘要： 传统重力波（GW）参数化忽略了GW动力学的三个方面。 它们不使用动量和熵通量，而是使用Eliassen-Palm通量，从而忽略了分辨流可能不在地转和静力平衡中的可能性。 通过在每个时间步确定如果垂直重力波传播是瞬时的，将产生的重力波通量的平衡剖面，它们忽略了重力波场和分辨流的瞬变性。 此外，它们也不考虑横向重力波传播和水平重力波通量。 由于预报性重力波模型MS-GWaM不需要做出这些假设，它已被用于全球天气和气候代码ICON中，以研究它们对月平均纬向平均流和太阳潮汐模拟结果的影响。 发现这三个方面都会显著影响模拟结果。 其中，瞬变性和横向传播的影响最强。 中间层和低热层的平均环流在所有纬度以及平流层高海拔地区都受到影响。 这与直接修改的重力波强迫一起，也导致了太阳潮汐的迁移和非迁移成分的显著差异。 如果同时考虑这两个方面，与从卫星数据中获取的潮汐比较最为有利。 这表明，在参数化中应相应地对重力波动力学进行广义处理，作为允许重力波模拟的高效替代方案。 显示英文摘要

摘要： Conventional gravity-wave (GW) parameterizations neglect three aspects of GW dynamics. Instead of momentum and entropy fluxes they use Eliassen-Palm fluxes, thereby neglecting the possibility that resolved flow are not in geostrophic and hydrostatic balance. They neglect the transience of the GW field and of the resolved flow, by determining at every time step equilibrium profiles of GW fluxes that would result if the vertical GW propagation were instantaneous. Moreover, they also do not take into account lateral GW propagation and horizontal GW fluxes. Because the prognostic GW model MS-GWaM does not need to make these assumptions, it has been used in the global weather and climate code ICON to investigate their consequences for the simulation of monthly mean zonal mean flows and of solar tides. All three aspects are found to influence the simulation results significantly. Among those, transience and lateral propagation have the strongest impact. The mean circulation in the mesosphere and lower thermosphere is affected at all latitudes and in the stratosphere at high altitudes as well. This together with the directly modified GW forcing leads also to significant differences in the migrating and nonmigrating components of solar tides. Comparisons with tides retrieved from satellite data are most favorable if both aspects are taken into account. This argues for a correspondingly generalized treatment of GW dynamics in their parameterization, as an efficient alternative to GW permitting simulations.