Toward a unified theory of atmospheric convective instabilityA nonlinear three-dimensional truncated spectral model of shallow and moist Boussinesq convection indicates that parallel instability and thermal forcing are linked, in view of the fact that only one convective mode exists in which either or both mechanisms are operating to generate convection in the planetary boundary layer. It is also established that the wind field causes two-dimensional roll convection formation, an alignment of the convection with the wind in a preferred manner, and a propagation speed that is related to the wind component perpendicular to the roll axis. Latent heating is responsible for the decrease of the critical value of the environmental lapse rate in accordance with the slice method stability criterion. When only the upper part of the upward branch is moist and all of the downward branch is dry, latent heating also causes a finite-amplitude convective solution for Rayleigh number values lower than the critical value of linear analysis.
Document ID
19830042741
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Shirer, H. N. (Pennsylvania State University University Park, PA, United States)
Date Acquired
August 11, 2013
Publication Date
January 1, 1982
Subject Category
Meteorology And Climatology
Meeting Information
Meeting: In: Cloud dynamics; Proceedings of the Symposium