[GTP] Seminar: TURBULENCE, CLOUDS AND CLIMATE MODELS

[Silvia Gentile]

CGD SEMINAR SERIESCGD SERIES
DATE: Monday, 28 July 2008
TIME: 12:30 – 1:30 p.m. (Brown Bag Lunch)
LOCATION: NCAR MESA LAB - 1850 Table Mesa Drive, Boulder, CO CHAPMAN ROOM
SPEAKER: JOÃO TEIXEIRA
JET PROPULSION LAB, PASADENA, CA
TITLE: TURBULENCE, CLOUDS AND CLIMATE MODELS

ABSTRACT:
Climate and weather prediction models are still quite inaccurate in 
representing clouds, turbulence, convection and the interaction between 
the ocean and the atmosphere. The problem is that these processes can 
occur in a variety of scales, from the planetary scale to very small 
scales that cannot be represented explicitly in any atmospheric model. A 
major challenge in climate and weather prediction is in how to improve 
the representation of these sub-grid scale physical processes: the 
parameterization problem.
This talk will focus on two major issues in particular: (i) how to 
represent the sub-grid scale turbulent motions and (ii) how to represent 
clouds. Recent model results from an international evaluation effort 
(the GCSS Pacific cross-section intercomparison – GPCI) will be 
presented in order to highlight major model deficiencies. New approaches 
for cloud parameterization that make use of probability density 
functions (pdfs) and unified parameterizations for turbulence and 
convection involving optimal combinations of Eddy-Diffusivity and 
Mass-Flux methods will be discussed in detail.