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@PhDThesis{Morais:2016:EsObNu,
               author = "Morais, Michelyne Duarte Coutinho de",
                title = "V{\'o}rtices cicl{\^o}nicos de altos n{\'{\i}}veis que atuam 
                         no nordeste do Brasil: estudo observacional e num{\'e}rico",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2016",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2016-02-22",
             keywords = "v{\'o}rtices cicl{\^o}nicos de altos n{\'{\i}}veis, nordeste 
                         do Brasil, simula{\c{c}}{\~o}es, observa{\c{c}}{\~o}es, upper 
                         tropospheric cyclonic vortices, northeastern Brazil, simulations, 
                         observations.",
             abstract = "Aspectos evolutivos dos V{\'o}rtices Cicl{\^o}nicos de Altos 
                         N{\'{\i}}veis (VCANs) do Nordeste do Brasil como estrutura 
                         vertical, precipita{\c{c}}{\~a}o associada e efeitos do 
                         aquecimento por condensa{\c{c}}{\~a}o na regi{\~a}o da 
                         periferia e proximidades s{\~a}o escassos na literatura. Com esta 
                         pesquisa desenvolveu-se um estudo observacional e num{\'e}rico da 
                         estrutura f{\'{\i}}sico-din{\^a}mica durante a 
                         evolu{\c{c}}{\~a}o destes sistemas. Inicialmente, examinaram-se 
                         as principais caracter{\'{\i}}sticas em diferentes est{\'a}gios 
                         do ciclo de vida atrav{\'e}s de uma climatologia objetiva para o 
                         per{\'{\i}}odo de 1984 a 2013, usando os dados das 
                         rean{\'a}lises do ERA-Interim. Verificou-se que na camada 200-500 
                         hPa, a intensidade destes sistemas {\'e} maior e mais 
                         vari{\'a}vel do que na camada 500-1000 hPa e que a maioria 
                         n{\~a}o apresentou inclina{\c{c}}{\~a}o ou a 
                         inclina{\c{c}}{\~a}o {\'e} para leste com a altura. Houve 
                         domin{\^a}ncia de sistemas que permanecem no n{\'{\i}}vel de 
                         200 hPa durante o desenvolvimento, contudo no est{\'a}gio de 
                         profundidade m{\'a}xima tamb{\'e}m predominaram v{\'o}rtices na 
                         camada 200-400 hPa. Em uma segunda etapa, um novo modelo 
                         conceitual foi elaborado por meio da t{\'e}cnica de campos 
                         compostos usando dados do ERA-Interim e do \emph{Prediction 
                         Center Morphing Method} (CMORPH), de 2003 a 2013. Este modelo 
                         descreve a evolu{\c{c}}{\~a}o do comportamento m{\'e}dio de 
                         vari{\'a}veis atmosf{\'e}ricas na troposfera entre o centro e a 
                         periferia de quatro grupos de v{\'o}rtices (profundos, rasos, 
                         lentos e r{\'a}pidos). Notou-se que os profundos mostraram 
                         consider{\'a}veis varia{\c{c}}{\~o}es horizontais de vento, 
                         temperatura, umidade e omega entre o centro e a periferia acima do 
                         n{\'{\i}}vel de 700 hPa. Essas varia{\c{c}}{\~o}es horizontais 
                         foram mais fracas e semelhantes entre os lentos e r{\'a}pidos, 
                         que se diferenciaram em termos din{\^a}micos. Em 
                         adi{\c{c}}{\~a}o, verificou-se que os profundos foram mais 
                         intensos e est{\~a}o associados {\`a} precipita{\c{c}}{\~a}o 
                         substancial. Por outro lado, os rasos foram mais fracos e se 
                         associaram a precipita{\c{c}}{\~a}o amena. Constatou-se que o 
                         desenvolvimento de convec{\c{c}}{\~a}o no centro dos 
                         v{\'o}rtices e proximidades {\'e} um poss{\'{\i}}vel 
                         indicativo para a dissipa{\c{c}}{\~a}o. Simula{\c{c}}{\~o}es 
                         num{\'e}ricas para um caso profundo foram executados com o modelo 
                         \emph{Weather Research and Forecasting} (WRF), for{\c{c}}ado com 
                         dados de an{\'a}lises do Global Forecast System (GFS). 
                         Investigou-se a influ{\^e}ncia do aquecimento por 
                         condensa{\c{c}}{\~a}o oriundo da convec{\c{c}}{\~a}o cumulus e 
                         da microf{\'{\i}}sica de nuvens na periferia do v{\'o}rtice e 
                         proximidades durante o desenvolvimento. Evid{\^e}ncias mostraram 
                         que os efeitos da redu{\c{c}}{\~a}o deste aquecimento foram: 
                         redu{\c{c}}{\~a}o do acumulado de precipita{\c{c}}{\~a}o e dos 
                         gradientes horizontais da temperatura e umidade entre o centro e a 
                         periferia do v{\'o}rtice. Entretanto, quando a 
                         redu{\c{c}}{\~a}o do aquecimento foi oriundo da 
                         convec{\c{c}}{\~a}o cumulus, o v{\'o}rtice se enfraqueceu, a 
                         profundidade se manteve, a inclina{\c{c}}{\~a}o com a altura foi 
                         vari{\'a}vel e o campo de vento em 200 hPa foi mais fraco e 
                         alterado. Ao contr{\'a}rio, quando este aquecimento foi derivado 
                         da microf{\'{\i}}sica de nuvens, o v{\'o}rtice se intensificou 
                         com profundidade maior, o campo de vento em 200 hPa mudou pouco e 
                         a inclina{\c{c}}{\~a}o do v{\'o}rtice com a altura foi similar 
                         {\`a} simula{\c{c}}{\~a}o controle. As simula{\c{c}}{\~o}es 
                         sem aquecimento latente reproduziram o v{\'o}rtice, embora aquela 
                         inicializada previamente gerou o VCAN em decorr{\^e}ncia da 
                         propaga{\c{c}}{\~a}o de energia cin{\'e}tica atrav{\'e}s de um 
                         trem de ondas. Essas simula{\c{c}}{\~o}es e a com 50\% de 
                         redu{\c{c}}{\~a}o do aquecimento latente pela 
                         convec{\c{c}}{\~a}o cumulus mantiveram o sistema por meio do 
                         trem de ondas, conduzindo a inferir que casos sem calor latente ou 
                         com nebulosidade associada podem ser mantidos por este processo 
                         din{\^a}mico. ABSTRACT: Information about the evolutionary 
                         aspects of the upper tropospheric cyclonic vortices (UTCVs) in 
                         northeastern Brazil, such as vertical structure, associated 
                         precipitation and over effects of heating by condensing in the 
                         periphery and nearby region is scarce in the literature. In this 
                         research is developed an observational and numerical study of the 
                         physical-dynamic structure and evolution of these systems. 
                         Initially, the UTCVs main features were examined in different life 
                         cycle stages through objective climatology, for the period from 
                         1984 to 2013, using data from ERA-Interim reanalysis. As noted, 
                         UTCVs in the 200-500 hPa layer had greater and more variable 
                         intensity than those in the 500-1000 hPa layer and majority 
                         presented no tilt or tilt to the east with height. There was 
                         dominance of UTCVs that remained at 200 hPa during evolution. 
                         However, in the hours of maximum depth, vortices also predominated 
                         in the 200-400 hPa layer. In the second phase of the study, a new 
                         conceptual model was formulated through composite fields technique 
                         using ERA-Interim data and the Prediction Center Morphing Method 
                         (CMORPH), from 2003 to 2013. This model describes the evolution of 
                         the average behavior of the atmospheric variables in the 
                         troposphere, between center and periphery, of four groups of the 
                         UTCVs (deep, shallow, slow and fast). We noted that the deep cases 
                         showed considerable horizontal wind, temperature, humidity and 
                         omega horizontal gradients between the center and periphery, above 
                         the 700 hPa level. These horizontal gradients were weaker and 
                         similar, between the slow and fast cases, which differed in 
                         dynamic terms. In addition, the deep cases were more intense, 
                         vertically extended and associated with considerable 
                         precipitation. On the other hand, the shallow cases were weaker 
                         with a lower vertical extension and milder precipitation. The 
                         development of convection in the center and closeness of UTCVs is 
                         a possible indication of dissipation. Numerical simulations, for 
                         one case of the deep vortex, were performed with the Weather 
                         Research and Forecasting (WRF) model, with data from Global 
                         Forecast System analyses (GFS). The Influence of heating by 
                         condensation from cumulus convection and cloud microphysics on the 
                         closeness and periphery of UTCVs was investigated. Evidence showed 
                         that the effects of this heating involve reduction of the 
                         cumulative precipitation and horizontal gradients of temperature 
                         and moisture between the center and vortex edge. However, when the 
                         reduction of the heating was derived from cumulus convection, the 
                         UTCV weakened, the depth remained the same and the wind field at 
                         200 hPa was weaker. In contrast, when this heating was derived 
                         from cloud microphysics, the vortex intensified, with greater 
                         depth, and the wind field at 200 hPa changed little. The vortex 
                         tilt with height was similar to the simulation control. The 
                         simulations without latent heating produced the vortex, although 
                         the one initialized previously generated the system as a result of 
                         kinetic energy propagating trough of a train of waves. These 
                         simulations and 50\% reduction of the latent heat by cumulus 
                         convection maintained the system through this wave train, leading 
                         to the inference that dry cases or those associated with 
                         cloudiness can be maintained by this dynamic process.",
            committee = "Ferreira, Nelson Jesuz (presidente) and Gan, Manoel Alonso 
                         (orientador) and Fernandez, Julio Pablo Reyes (orientador) and 
                         Rivero, Silvio Nilo Figueroa and Gandu, Adilson Wagner and Souza, 
                         Enio Pereira de",
           copyholder = "SID/SCD",
         englishtitle = "Upper tropospheric cyclonic vortices act in the northeastern 
                         Brazil: observational and numerical study",
             language = "pt",
                pages = "261",
                  ibi = "8JMKD3MGP3W34P/3L3FGTS",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3L3FGTS",
           targetfile = "publicacao.pdf",
        urlaccessdate = "29 nov. 2020"
}


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