HR: 08:30h
AN: NG41A-03    [PDF]
TI: Strategies for the Use of Scaling for Subgrid Parameterizations for Globbal Circulation Models of the Atmosphere
AU: * Tribbia, J
EM: tribbia@ucar.edu
AF: NCAR, Box 3000, Boulder, CO 80307 United States
AB: The problem of parameterization of physical process in large scale numerical models of the atmosphere will be developed first from a formal perspective of specifying sub-grid effects as distributions conditional upon resolved scales of motions. Historically, focus has been concentrated upon models of the 'average' or mean tendencies and the models have been of two classes: sub-grid models which depend upon scale similarity and those which are developed from idealized process models. The Smagorinsky eddy diffusion is the most notable use of scale similarity arguments in parameterizations for large scale models. However, for many other sub-grid physical processes little use of scaling structure has been utilized in the development of parameterizations. I will describe some recent efforts and new strategies aimed at moving beyond the use of non-scaling process models for the computation of the subgrid tendencies due to subgrid effects of clouds, cumulus convection, orographic drag and radiation. The major complication in the pure scale similarity approach or the process model approach to parameterization is the spatio-temporal intermittency of meso and micro scale atmospheric motions which must be accounted for.
DE: 3210 Modeling
DE: 3220 Nonlinear dynamics
DE: 3250 Fractals and multifractals
SC: Nonlinear Geophysics [NG]
MN: 2003 Fall Meeting