Momentum Balance and Eliassen–Palm Flux on Moist Isentropic Surfaces
Momentum Balance and Eliassen–Palm Flux on Moist Isentropic Surfaces
复制标题
潮湿等熵表面上的动量平衡和 Eliassen-Palm 通量
DOI：
10.1175/jas-d-15-0229.1
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发表时间：
2016
影响因子：
3.1
通讯作者：
O. Pauluis
中科院分区：
文献类型：
--
作者：
R. Yamada;O. Pauluis
摘要：以前的区域平均动量预算和 Eliassen-Palm (EP) 通量诊断的公式没有充分考虑潮湿动力学，因为在取平均值时，空气块不会根据其湿度含量进行区分。在湿坐标中制定动量预算的困难在于它们通常不可逆于高度。这里，使用条件平均方法根据不假定可逆的一般垂直坐标导出动量预算和 EP 通量的弱公式。广义方程简化为可逆垂直坐标的典型质量加权区域平均动量方程。这里应用弱公式来研究湿等熵上的动量收支。最近的研究表明，中纬度地区潮湿等熵线的经向质量传输强度是干燥等熵线的两倍。此处显示，这意味着干层之间的 EP 通量有类似的增加...
AbstractPrevious formulations for the zonally averaged momentum budget and Eliassen–Palm (EP) flux diagnostics do not adequately account for moist dynamics, since air parcels are not differentiated by their moisture content when averages are taken. The difficulty in formulating the momentum budget in moist coordinates lies in the fact that they are generally not invertible with height. Here, a conditional-averaging approach is used to derive a weak formulation of the momentum budget and EP flux in terms of a general vertical coordinate that is not assumed to be invertible. The generalized equation reduces to the typical mass-weighted zonal-mean momentum equation for invertible vertical coordinates.The weak formulation is applied here to study the momentum budget on moist isentropes. Recent studies have shown that the meridional mass transport in the midlatitudes is twice as strong on moist isentropes as on dry isentropes. It is shown here that this implies a similar increase in the EP flux between the dry...