HR: 1340h
AN: A53A-0858    [Abstracts]
TI: Comparison of Radix Similarity and Level 2.5 Turbulent Parameterization Scheme in the Prediction of Wind and Temperature Profiles in the Convective Boundary Layer
AU: * Feng, X
EM: fengx@psu.edu
AF: Department of Meteorology, The Pennsylvania State University, University Park, PA 16802
AB: Santoso and Stull (1998, 2001) propose radix similarity equation (RSE) to describe the mean wind speed and potential temperature profiles in the radix layer (RxL): roughly the bottom fifth of the convective boundary layer. Their results suggest that the observations within the RxL collapse into similarity curves. The good ability of RSE in capturing the convective boundary structure motivates us this work to gain some insight on the appropriate treatment of boundary layer physical processes and the parameterization of turbulent transport processes. This work aims to compare the wind and temperature profiles predicted with radix similarity equation (RSE) and a level 2.5 turbulent parameterization scheme that currently in used in MM5 1-D model against First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE) data. The preliminary results suggest that RSE realistically represent the evolvement of the wind and temperature in the convective boundary layer. MM5 1-D model simulation underestimates wind and overestimates potential temperature near the surface. Future work will attempt to carry out more comparisons among the selected observation cases using RSE to further investigate the deficiencies of the current turbulent scheme. Then the good aspect of RSE will be applied to the actual turbulent parameterization scheme to help improve model performance.
DE: 3307 Boundary layer processes
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting