NUMERICAL SIMULATION OF TWO MESOSCALE CONVECTIVE SYSTEMS USING THE WRF MODEL

Kauan Vargas Casarin

Abstract


The model Weather Research and Forecasting (WRF) was used in order to simulate two Mesoscale Convective Systems (MCSs) with different characteristics in order to analyze how variables such as wind directional shear and  thickness gradient are modified within the MCSs along its entire duration. The first event is a linear MCS that extended from the north of Argentina to the South Atlantic in November 30, 2009 and the second is a circular MCS or MCC (mesoscale convective complex) that occurred on the RS and Uruguay on November 18, 2009. The two systems were identified through images of the satellite GOES (Geostationary Operational Environmental Satellite) using an automatic tracking of MCSs and for the simulation of events in WRF we used the data reanalysis of CFSR (Climate Forecast System Reanalysis). The simulation results indicated that the rate of reduction thickness gradient is greater in the circular case than in the linear case and at the time that events are initiated the wind directional shear is higher in the linear case but he reduces until the moment of dissipation of the MCS different than occurs in MCC, which has an increased wind directional shear when the system is almost dissipating.

Keywords


MCS. Mesoscale. WRF. Shear. Thickness.

References


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DOI: http://dx.doi.org/10.5902/2179460X19994

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