The slowly evolving background state of the atmosphere
The slowly evolving background state of the atmosphere
复制标题
缓慢演变的大气背景状态
DOI：
10.1002/qj.2518
复制
发表时间：
2015
影响因子：
8.9
通讯作者：
P. Berrisford
中科院分区：
文献类型：
--
作者：
J. Methven;P. Berrisford
波-平均流相互作用理论要求将大气流划分为一个概念上的背景状态和扰动，这里的背景状态被称为修正的拉格朗日平均（MLM），它被定义为纬向对称状态，通过要求等熵层内的每个位涡（PV）等值线包围的质量和环流与全流相同而获得。对于绝热和无摩擦流动，这两个积分性质是时不变的，并且MLM状态是原始方程的稳定解。绝热流中的时间依赖性被放入微扰中，这可以通过波活动守恒定律来描述，即使在大振幅下也是精确的。此外，非保守过程对波活动的影响可以从守恒定律计算出来。
The theory of wave–mean flow interaction requires a partition of the atmospheric flow into a notional background state and perturbations to it. Here, a background state, known as the Modified Lagrangian Mean (MLM), is defined as the zonally symmetric state obtained by requiring that every potential vorticity (PV) contour lying within an isentropic layer encloses the same mass and circulation as in the full flow. For adiabatic and frictionless flow, these two integral properties are time‐invariant and the MLM state is a steady solution of the primitive equations. The time dependence in the adiabatic flow is put into the perturbations, which can be described by a wave‐activity conservation law that is exact even at large amplitude. Furthermore, the effects of non‐conservative processes on wave activity can be calculated from the conservation law.
影响因子：
8.9
作者：
J. Chagnon;S. Gray;J. Methven
通讯作者：
J. Chagnon;S. Gray;J. Methven
影响因子：
3.1
作者：
-N.;J. Matthewman;G. J.;Esler
通讯作者：
-N.;J. Matthewman;G. J.;Esler
用于显示天文强度图像的配色方案
影响因子：
--
作者：
Green D. A.
通讯作者：
Green D. A.