NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Collections About News Help Login
Back to Results
The Impact of Microphysics and Planetary Boundary Layer Physics on Model Simulation of U.S. Deep South Summer ConvectionInspection of output from various configurations of high-resolution, explicit convection forecast models such as the Weather Research and Forecasting (WRF) model indicates significant sensitivity to the choices of model physics pararneterizations employed. Some of the largest apparent sensitivities are related to the specifications of the cloud microphysics and planetary boundary layer physics packages. In addition, these sensitivities appear to be especially pronounced for the weakly-sheared, multicell modes of deep convection characteristic of the Deep South of the United States during the boreal summer. Possible ocean-land sensitivities also argue for further examination of the impacts of using unique ocean-land surface initialization datasets provided by the NASA Short-term Prediction Research and Transition (SPoRn Center to select NOAAlNWS weather forecast offices. To obtain better quantitative understanding of these sensitivities and also to determine the utility of the ocean-land initialization data, we have executed matrices of regional WRF forecasts for selected convective events near Mobile, AL (MOB), and Houston, TX (HGX). The matrices consist of identically initialized WRF 24-h forecasts using any of eight microphysics choices and any of three planetary boWldary layer choices. The resulting 24 simulations performed for each event within either the MOB or HGX regions are then compared to identify the sensitivities of various convective storm metrics to the physics choices. Particular emphasis is placed on sensitivities of precipitation timing, intensity, and coverage, as well as amount and coverage oflightuing activity diagnosed from storm kinematics and graupel in the mixed phase layer. The results confirm impressions gleaned from study of the behavior of variously configured WRF runs contained in the ensembles produced each spring at the Center for the Analysis and Prediction of Storms, but with the benefit of more straightforward control of the physics package choices. The design of the experiments thus allows for more direct interpretation of the sensitivities to each possible physics combination. The results should assist forecasters in their efforts to anticipate and correct for possible biases in simulated WRF convection patterns, and help the modeling community refine their model parameterizations.
Document ID
20140008783
Acquisition Source
Marshall Space Flight Center
Document Type
Presentation
Authors
McCaul, Eugene W., Jr. (Universities Space Research Association Huntsville, AL, United States)
Case, Jonathan L. (ENSCO, Inc. Huntsville, AL, United States)
Zavodsky, Bradley T. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Srikishen, Jayanthi (Universities Space Research Association Huntsville, AL, United States)
Medlin, Jeffrey M. (National Oceanic and Atmospheric Administration Highlands, NJ, United States)
Wood, Lance (National Oceanic and Atmospheric Administration Highlands, NJ, United States)
Date Acquired
July 8, 2014
Publication Date
February 6, 2014
Subject Category
Meteorology And Climatology
Report/Patent Number
M14-3298
Meeting Information
Meeting: AMS Annual Meeting
Location: Atlanta, GA
Country: United States
Start Date: February 2, 2014
End Date: February 6, 2014
Sponsors: American Meteorological Society
Distribution Limits
Public
Copyright
Public Use Permitted.

Related Records

IDRelationTitle20140006923See AlsoThe Impacts of Microphysics and Planetary Boundary Layer Physics on Model Simulations of U. S. Deep South Summer Convection
No Preview Available