Troposphere-Stratosphere Coupling Processes

对流层和平流层之间动量、能量和微量组分的传递是决定平流层动力学和化学气候学的关键，对对流层上部也有重要意义。 平流层的动量平衡对垂直传播的重力波穿过对流层顶的动量转移很敏感，重力波的范围从行星尺度到小尺度。 对平流层臭氧平衡至关重要的化学过程取决于微量成分穿过对流层顶的转移。 因此，了解对流层-平流层的耦合对于了解平流层的全球环流、臭氧层的化学以及对流层上部的化学和气候至关重要。 此外，垂直传播的重力波的影响延伸到中间层，在那里它们是环流纬向强迫的主要因素，也是产生较小尺度二次波的来源。对流风暴和飑线是产生垂直传播重力波的重要来源。 在他们以前的工作中，PI使用二维模型来研究动量转移。 在这个奖项下，他们将把大部分工作扩展到三个维度，包括平流层和中间层，研究对大规模环流的影响。 此外，PI将使用其三维云模型研究示踪剂传输。另一个不是以往工作延伸的专题是研究平流层迁移环流及其与所谓“北极涛动”的关系。 研究人员将探讨地形强迫行星波与观测到的北极涛动之间的相似性以及与平流层环流的关系。

Transfer of momentum, energy, and trace constituents between the troposphere and the stratosphere is crucial for determining the dynamical and chemical climatology of the stratosphere, and is also of significance for the upper troposphere. The momentum balance in the stratosphere is sensitive to momentum transfer across the tropopause by vertically propagating gravity waves ranging from planetary scale to small-scale. Chemical processes crucial to the stratospheric ozone balance depend on the transfer of trace constituents across the tropopause. Thus, the understanding of the troposphere-stratosphere coupling is essential for understanding the global circulation of the stratosphere, the chemistry of the ozone layer, and the chemistry and climate of the upper troposphere. Moreover, the influence of the vertically propagating gravity waves extends well into the mesosphere where they are a major factor in the zonal forcing of the circulation as well as a source for the generation of smaller scale secondary waves. Convective storms and squall lines are significant sources for the generation of vertically propagating gravity waves. In their previous work, the PIs used a two-dimensional model to study the momentum transfer. Under this award, they will extend much of that work to three dimensions, both in the stratosphere and mesosphere, examining the effects on the large-scale circulations. In addition, the PIs will study tracer transport using their three-dimensional cloud model. An additional topic that is not an extension of previous work is the study of the stratospheric transport circulation and its relation to the so-called "Arctic Oscillation". The PIs will explore the similarity between topographically-forced planetary waves and the observed Arctic Oscillation and the relationship to the stratospheric circulation.