Modelo de Area Limitada de Cinco Camadas Para Previsao Numerica de Tempo (Model of Limited Area of 5 Layers for Numerical Weather Forcasting)

摘要

A primitive prognostic equation model, with horizontal spherical coordinates, and vertical sigma coordinates, was developed for use in numerical weather forecasting. The model programming has a modular structure that will easily allow the inclusion of the parameterizations of subgrid scale phenomena. The model has characteristics that attenuate computational effects and increase efficiency. The horizontal grid encloses all of South America, parts of Central America, and parts of adjacent oceans. The vertical grid has five layers, extending from surface up to 50 mb and a shallow lower layer intended for future boundary layer parameterization implementation. Radiational boundary conditions are used at eastern and western boundaries and zero meridional flux conditions at southern and northern boundaries. The model will be part of a complete operational scheme for weather forecasting. In order to verify the stability and performance of the model an experiment is made to simulate the circulation of the Bolivian High, which is generated by transient heat sources. The results show that the model is stable and has satisfactory performance for the examined case.