Estudo da sensibilidade das parametrizações físicas de cumulus no modelo WRF-UEMS em eventos convectivos intensos sobre a região oeste do Pará.

Abstract

The objective of this study is the use of physical parameterizations of cumulus clouds in numerical simulations of nighttime convective events over the western region of Pará in order to know what the performance of each scheme is on a case study. With this, we tried to understand and quantify the uncertainties through statistical indices, instability and simulations with version 1λ.8.1 of the model Weather Research and Forecasting - Unified Environmental Modeling System (WRF UEMS), using data from weather station and reanalysis. The reason why this proposal is being launched, is based on some local and specific meteorological rain phenomena that have been frequently observed for years over the western region of Pará and that have not yet been studied in order to understand in the context of numerical modeling of the atmosphere. The cumulus parameterizations used in this work wereμ Grell-3D, Grell-Freitas, Multi-Scale-KF and Multi Scale-KF-Cup. In the comparison between the data from the meteorological station and the parameterized reanalysis, it was found that the simulations with Grell-3D and Multi-Scale-KF Cup were the ones that obtained the best statistical indicators. The air temperature measurements at 2 m in the other configurations showed a marked difference, reflected in the statistical indices. The use of the IK and Total Totals indexes had the function of assisting in the analysis of the behavior of the variables in view of the physical parameterizations in high resolution simulations. From the analysis of the meteorological fields simulated with the Grell-3D parameterization, which obtained better indexes, it was possible to identify, with the aid of satellite images, the large scale performance of the Intertropical Convergence Zone acting on the coast of Pará and the propagation of squall lines into the interior of the Amazon Basin. With the parameterization of the best index, results were obtained that managed to represent a convective environment in before, during and after the passage of an intense convective system. The main problems that were detected are mainly related to the excess of configurations in inappropriate boundary conditions. In this case, the most traditional configurations in their terms were the ones that most obtained values statistically appropriate to the expected for the simulations. This work that started tests on the performance of convective parameterizations in the region, opening an important path for atmospheric research on the Amazon region in a more local concept.