Sunday, 9 February 2003
The Energetics of a Moist Nonlinear Buoyancy Oscillation in a Statically Stable Environment
Paul Thomas Quelet, The Pennsylvania State University Department of Meteorology, University Park, PA; and P. R. Bannon
In a statically stable atmosphere, the Brunt-Vaisala frequency can assess the stability of a displaced parcel of air by characterizing a period of oscillation given a finite displacement from a neutral equilibrium position. Past research has suggested various forms for a moist Brunt-Vaisala frequency the accounts for changes in buoyancy for a parcel's motion given a certain atmospheric moisture content that plays a role in the heating and cooling of the parcel on ascent and descent. Furthering this result, this study generalizes a moist buoyancy oscillation and is examined by a simple numerical model in the context of one-dimensional vertical displacements.
The governing equations for these experiments are detailed while a description of the model simulations are provided. The calculations focus on examining the traditional, kinetic, and potential energetics of the moist parcel. The equations are considered in full non-linear form. This study seeks to better understand the magnitudes and transfers of the moist parcel energetics in an idealized one-dimensional environment for various parcel scenarios.
This study reveals similarities to the dry oscillation as wells as results from the linear approximation that can be assumed under certain conditions. In addition, this analysis identifies unmet challenges in expressing moist available potential energy at a point in space along a parcel trajectory.
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