Application of the STMAS data assimilation system in a tornadogenesis numerical simulation
Abstract
Fine-resolution data assimilation and numerical simulation are critical for tornadogenesis and forecasts. The May 2008 Windsor (Colorado) tornado is selected as a numerical case study using the Weather Research and Forecasting (WRF) model. The Space and Time Multiscale Analysis System (STMAS) including improved humidity analysis and assimilation of thermodynamic and liquid profiles from a microwave radiometer are used to produce initial conditions, while the background information is provided by the Rapid Update Cycle (RUC) model. The impact of data assimilation on tornadogensis and tornadic development has been investigated. The synoptic factors, including wind, temperature, and humidity, are analyzed during the life cycle of the tornado. Several thermodynamic quantities of the tornado, such as helicity, vorticity, wind shear, CAPE, and downdraft, are also presented to help understand the mechanism of tornadogensis and maintenance processes. The diabatic initialization (hot start) with different humidity analysis and the physical schemes in the WRF model could contribute to the rapid tornado evolution. In addition, the preliminary results using the STMAS initialization are compared with the simulation initialized by the WRF 3D variational (WRF-3DVar) method.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2012
- Bibcode:
- 2012AGUFM.A11E0081Y
- Keywords:
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- 3314 ATMOSPHERIC PROCESSES / Convective processes;
- 3315 ATMOSPHERIC PROCESSES / Data assimilation;
- 4301 NATURAL HAZARDS / Atmospheric