Problemas inversos em física da atmosfera

• Ano de defesa: 2005
• Autor(a) principal: Roberti, Débora Regina
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; BR; Física; UFSM; Programa de Pós-Graduação em Física
• Palavras-chave em Português: Problema inverso; Estimação de fontes; Estimação de parâmetros atmosféricos; Inverse problem; Source estimation; Atmospheric parameters estimation; CNPQ::CIENCIAS EXATAS E DA TERRA::FISICA
• Link de acesso: http://repositorio.ufsm.br/handle/1/3940

Techniques for estimating unknown terms - such as eddy diffusivity and counter-gradient - in atmospheric flow are presented in this study. The methos is also used to identify the source term in atmospheric pollution. The scheme adopted is based on inverse problem methodology. The inverse problem is formulated as a non-linear optimization problem, where the objective function is defined as the square difference between observational data and data from a transport mathematical model. For estimating the properties of the atmospheric flux, an implicit strategy was used, and an Eulerian model was used as forward model. The estimation of the pollutant source term was tested employing a source-repector technique. In the pollutant dispersion simulation, a Lagrangian model was applied. For some inversions, regularized solutions should be searched. The Tikhonov and entropy regularizations were considered. Three different optimization methods were used: Levenberg-Marquardt, quasi-Newton (deterministic) e simulated annealing (stochastic). The results show a good performance of the proposed methodology in many tested situations.