Open AccessAn alternative scaling for unsteady penetrative free convection
Author(s) -
Catalano Franco,
Moroni Monica,
Dore Valentina,
Cenedese Antonio
Publication year - 2012
Publication title -
journal of geophysical research: atmospheres
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2012jd018229
Subject(s) - scaling , convective boundary layer , convection , mechanics , turbulence , boundary layer , large eddy simulation , planetary boundary layer , thermal , homogeneous , meteorology , physics , geology , geophysics , statistical physics , geometry , mathematics
The daytime evolution of the atmospheric boundary layer under high pressure, anticyclonic synoptic systems over a homogeneous terrain can be successfully described by a penetrative free convection model, evolving from an initially stably stratified environment. In this article dimensional analysis has been employed to derive a new set of scaling parameters, which are functions of external, time‐dependent, fluid properties and boundary conditions. This novel theoretical framework has been adopted to compare laboratory scale experiments, performed using a thermally controlled water tank and a Large Eddy Simulation (LES) numerical model. Both these have been developed for the characterization of the instabilities associated with the development of the Convective Boundary Layer (CBL). The characteristic length and time scales of the thermal plumes, their spatial distribution and interaction with the overlying stable layer are analyzed. The proposed scaling parameters appear to be representative of the bulk and turbulent properties of the CBL, as confirmed by both numerical and laboratory results.