Topical Problems of Fluid Mechanics


Institute of Thermomechanics AS CR, v.v.i.	CTU in Prague Faculty of Mech. Engineering Dept. Tech. Mathematics	MIO Université du Sud Toulon Var - AMU - CNRS - IRD	Czech Pilot centre ERCOFTAC

Influence of Moist Convection and Precipitation upon Developing Barotropic Instability of Vortices in the Moist-Convective Rotating Shallow Water Model
Rostami M., Zeitlin V.
Abstract:
Analysis of the influence of condensation and related moist convection upon developing barotropic instability of large-scale shielded cyclonic and anticyclonic vortices is undertaken within the moist-convective rotating shallow water. Numerical simulations of the saturation of the instability are performed with high-resolution well-balanced finite-volume model, with relaxation parameterization for condensation/precipitation. Evolutions of the instability in four different environments, with humidity (i) behaving as passive scalar, (ii) subject to precipitation beyond a saturation threshold, (iii) subject to precipitation and evaporation, with two different parameterizations of the latter, are intercompared. The simulations are initialized with the most unstable modes determined from the linear stability analysis. It is shown that the known scenario of "dipolar breakdown" is substantially modified by condensation and related moist convection, especially in the presence of evaporation. Inertia-gravity wave emission during the vortex evolution is enhanced by the moist effects.
Keywords:
instabilities, moist convection, gravity wave emission

Fulltext: PDF DOI: http://dx.doi.org/10.14311/TPFM.2016.027

In Proceedings Topical Problems of Fluid Mechanics 2016, Prague, 2016 Edited by David Šimurda and Tomáš Bodnár, pp. 195-206 ISBN 978-80-87012-58-1 (Print) ISSN 2336-5781 (Print)