Synoptic Responses to Mountain Gravity Waves Encountering Directional Critical Levels

From: Journal of the Atmospheric Sciences | Date: March 1, 2007| Author: | Copyright information

ABSTRACT

A heuristic model is used to study the synoptic response to mountain gravity waves (GWs) absorbed at directional critical levels. The model is a semigeostrophic version of the Eady model for baroclinic instability adapted by Smith to study lee cyclogenesis. The GWs exert a force on the large-scale flow where they encounter directional critical levels. This force is taken into account in the model herein and produces potential vorticity (PV) anomalies in the midtroposphere.

First, the authors consider the case of an idealized mountain range such that the orographic variance is well ...

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