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@MastersThesis{Costa:2015:EsCaSu,
               author = "Costa, Graziela Luzia da",
                title = "Estudo das causas da subestimativa da precipita{\c{c}}{\~a}o em 
                         previs{\~a}o de tempo pelo novo modelo atmosf{\'e}rico global do 
                         CPTEC (vers{\~a}o 4.1) sobre a regi{\~a}o da Bacia do Prata",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2015",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2015-05-29",
             keywords = "AGCM-CPTEC/INPE, precipita{\c{c}}{\~a}o, bacia do Prata, 
                         precipitation, La Plata basin.",
             abstract = "O Modelo de Circula{\c{c}}{\~a}o Geral Atmosf{\'e}rico (MCGA) 
                         do Centro de Previs{\~a}o de Tempo e Estudos Clim{\'a}ticos do 
                         Instituto Nacional de Pesquisas Espaciais (CPTEC/INPE) subestima 
                         sistematicamente a previs{\~a}o de precipita{\c{c}}{\~a}o sobre 
                         a regi{\~a}o da Bacia do Prata, sobretudo na regi{\~a}o sul do 
                         Brasil. Esta diferen{\c{c}}a {\'e} observada em rodadas longas, 
                         por{\'e}m, em integra{\c{c}}{\~o}es curtas j{\'a} {\'e} 
                         poss{\'{\i}}vel notar esta falha, com VI{\'E}S negativo nas 
                         previs{\~o}es de 1 a 5 dias. Neste trabalho, foi proposto 
                         investigar as poss{\'{\i}}veis causas dessa falha na 
                         previs{\~a}o de tempo utilizando-se a nova vers{\~a}o do MCGA 
                         (v.4.1) apresentando cinco hip{\'o}teses, sendo elas: 1) as 
                         falhas em simular a precipita{\c{c}}{\~a}o na regi{\~a}o 
                         s{\~a}o devidas a baixa resolu{\c{c}}{\~a}o do modelo; 2) o 
                         esquema de parametriza{\c{c}}{\~a}o da superf{\'{\i}}cie 
                         n{\~a}o simula adequadamente os processos de troca de umidade 
                         pr{\'o}ximo a superf{\'{\i}}cie, o que pode gerar um deficit na 
                         umidade dispon{\'{\i}}vel na camada limite planet{\'a}ria; 3) o 
                         modelo de microf{\'{\i}}sica de nuvens falha ao simular os 
                         processos de forma{\c{c}}{\~a}o de precipita{\c{c}}{\~a}o; 4) 
                         os padr{\~o}es de circula{\c{c}}{\~a}o da atmosfera na 
                         Am{\'e}rica do Sul, incluindo os Jatos de Baixos N{\'{\i}}veis 
                         (JBN) e suas consequ{\^e}ncias na forma{\c{c}}{\~a}o de chuva 
                         na regi{\~a}o da Bacia do Prata, n{\~a}o est{\~a}o sendo bem 
                         simulados e 5) efeitos n{\~a}o-locais, como a m{\'a} 
                         representa{\c{c}}{\~a}o de sistemas de escala global atuando 
                         sobre o sul do Oceano Pac{\'{\i}}fico ou {\'{\I}}ndico, 
                         favorecendo precipita{\c{c}}{\~a}o em locais equivocados e seca 
                         na regi{\~a}o da Bacia do Prata. Os resultados mostraram que a 
                         vers{\~a}o em alta resolu{\c{c}}{\~a}o do MCGA (T666L64, 20 km 
                         de resolu{\c{c}}{\~a}o horizontal) sem nenhum ajuste nas 
                         parametriza{\c{c}}{\~o}es f{\'{\i}}sicas apresenta muito pouca 
                         melhora na previs{\~a}o de chuva na regi{\~a}o de estudo em 
                         rela{\c{c}}{\~a}o a vers{\~a}o T299L64 (45 km). Da mesma 
                         maneira, os testes com diferentes parametriza{\c{c}}{\~o}es de 
                         microf{\'{\i}}sica e de superf{\'{\i}}cie apresentaram pouca 
                         diferen{\c{c}}a em rela{\c{c}}{\~a}o ao experimento controle. 
                         Os padr{\~o}es de circula{\c{c}}{\~a}o sobre a Am{\'e}rica do 
                         Sul, no geral, est{\~a}o sendo bem representados pelo MCGA, 
                         embora diferen{\c{c}}as na distribui{\c{c}}{\~a}o da umidade 
                         tenha sido observada durante o per{\'{\i}}odo com 
                         ocorr{\^e}ncia de JBN. Os resultados obtidos n{\~a}o foram 
                         conclusivos sobre a causa da subestimativa da 
                         precipita{\c{c}}{\~a}o em estudo, pois em alguns casos o deficit 
                         de chuva sobre a regi{\~a}o do Prata esteve associado ao erro do 
                         modelo em simular o JBN, enquanto em outros n{\~a}o. A 
                         avalia{\c{c}}{\~a}o das previs{\~o}es de bloqueios pelo MCGA 
                         mostrou que, para previs{\~o}es com 24 h de anteced{\^e}ncia, o 
                         modelo apresentou boa destreza, ao contr{\'a}rio das 
                         previs{\~o}es para 120 h, em que o modelo n{\~a}o foi capaz de 
                         simular t{\~a}o bem todos os eventos, bem como sua 
                         localiza{\c{c}}{\~a}o e intensidade. Entretanto, n{\~a}o foi 
                         encontrada rela{\c{c}}{\~a}o entre bloqueios nos oceanos 
                         {\'{\I}}ndico e Pac{\'{\i}}fico Central e Oeste com a chuva 
                         sobre a regi{\~a}o do Prata. Existem evid{\^e}ncias, embora 
                         n{\~a}o conclusivas, de que erros na simula{\c{c}}{\~a}o de 
                         bloqueios ao oeste do Chile (Oceano Pac{\'{\i}}fico leste) podem 
                         gerar erros na precipita{\c{c}}{\~a}o sobre a regi{\~a}o de 
                         estudo. ABSTRACT: The Atmospheric General Circulation Model (AGCM) 
                         from CPTEC/INPE systematicalIy underestimates the prediction of 
                         rainfalI over La Plata Basin, especialIy in southern Brazil. This 
                         difference is observed on long simulations, however in short 
                         integrations it is already possible to notice this failure with 
                         negative BIAS in forecasts for 1-5 days. In this work, it was 
                         proposed to investigate the possible causes of failure in forecast 
                         using the new version of MCGA (v.4.1) featuring five hypotheses, 
                         which are: 1) the failure to simulate the rainfalI in the region 
                         are due to low resolution model; 2) the surface parameterization 
                         scheme does not adequately simulate the moisture exchange 
                         processes near the surface, which can generate a deficit in 
                         moisture available in the planetary boundary layer; 3) 
                         microphysics scheme fails to simulate the cloud precipitation 
                         formation process; 4) atmospheric circulation patČterns in South 
                         America, including the low level jets (LLJ) and its consequences 
                         in the rain formation over La Plata Basin region are not well 
                         simulated and 5) this Iailure may be related to non-local effects 
                         such as the misrepresentation of global systems acting on the 
                         South Pacific or Indian Ocean, favoring precipitation in wrong 
                         places and drought in the La Plata Basin. The results showed that 
                         the high resoluČtion version of the.ACGM (T666L64, 20 km 
                         horizontal resolution) shows very little improvement in the rain 
                         prediction over the T299 version (45 km), simmilar the tests with 
                         different parameterizations of microphysics and surface. The 
                         circulation patterns over South America, in general, are being 
                         well represented by the ACGM. meanwhile differences in 
                         distribuction of humidity have been observed during period with 
                         LLJ occurrence. Results for this item were inconclusive as the 
                         cause of underestimation because in some cases the rain deficit 
                         over la Plata region it was associated with model error in 
                         simulating the LLJ, while in others noto The study of atmospheric 
                         blockings prediction by ACGM showed that for forecasts 24 hours in 
                         advance, the model showed good results, oposite to predictions for 
                         120h, where the model was not able to simulate so well all events 
                         as well as its location and intensity. However, it was not found 
                         relationship between atmospheric blockings in the Indian Ocean and 
                         the Pacific Central and West with rain on the La Plata region. 
                         There is evidence, though not conclusive, that errors in the 
                         atmospheric blocking simulation over west of Chile (eastern 
                         Pacific) can generate errors in precipitation over study area. 
                         ABSTRACT: The Atmospheric General Circulation Model (AGCM) from 
                         CPTEC/INPE systematicalIy underestimates the prediction of 
                         rainfalI over La Plata Basin, especialIy in southern Brazil. This 
                         difference is observed on long simulations, however in short 
                         integrations it is already possible to notice this failure with 
                         negative BIAS in forecasts for 1-5 days. In this work, it was 
                         proposed to investigate the possible causes of failure in forecast 
                         using the new version of MCGA (v.4.1) featuring five hypotheses, 
                         which are: 1) the failure to simulate the rainfalI in the region 
                         are due to low resolution model; 2) the surface parameterization 
                         scheme does not adequately simulate the moisture exchange 
                         processes near the surface, which can generate a deficit in 
                         moisture available in the planetary boundary layer; 3) 
                         microphysics scheme fails to simulate the cloud precipitation 
                         formation process; 4) atmospheric circulation patterns in South 
                         America, including the low level jets (LLJ) and its consequences 
                         in the rain formation over La Plata Basin region are not well 
                         simulated and 5) this Iailure may be related to non-local effects 
                         such as the misrepresentation of global systems acting on the 
                         South Pacific or Indian Ocean, favoring precipitation in wrong 
                         places and drought in the La Plata Basin. The results showed that 
                         the high resolution version of the.ACGM (T666L64, 20 km horizontal 
                         resolution) shows very little improvement in the rain prediction 
                         over the T299 version (45 km), simmilar the tests with different 
                         parameterizations of microphysics and surface. The circulation 
                         patterns over South America, in general, are being well 
                         represented by the ACGM. meanwhile differences in distribuction of 
                         humidity have been observed during period with LLJ occurrence. 
                         Results for this item were inconclusive as the cause of 
                         underestimation because in some cases the rain deficit over la 
                         Plata region it was associated with model error in simulating the 
                         LLJ, while in others noto The study of atmospheric blockings 
                         prediction by ACGM showed that for forecasts 24 hours in advance, 
                         the model showed good results, oposite to predictions for 120h, 
                         where the model was not able to simulate so well all events as 
                         well as its location and intensity. However, it was not found 
                         relationship between atmospheric blockings in the Indian Ocean and 
                         the Pacific Central and West with rain on the La Plata region. 
                         There is evidence, though not conclusive, that errors in the 
                         atmospheric blocking simulation over west of Chile (eastern 
                         Pacific) can generate errors in precipitation over study area.",
            committee = "Moscati, Marley Cavalcante de Lima (presidente) and Bonatti, 
                         Jos{\'e} Paulo (orientador) and Rivero, Silvio Nilo Figueroa 
                         (orientador) and Marques, Rosa de F{\'a}tima Cruz",
           copyholder = "SID/SCD",
         englishtitle = "Causes of underestimation of precipitation in forecasting by the 
                         new global atmospheric circulation model (AGCM-CPTEC/INPE V. 4.1) 
                         over La Plata Basin",
             language = "pt",
                pages = "83",
                  ibi = "8JMKD3MGP3W34P/3JTUQQS",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3JTUQQS",
           targetfile = "publicacao.pdf",
        urlaccessdate = "29 nov. 2020"
}


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