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@MastersThesis{António:2020:EnZoCo,
               author = "Ant{\'o}nio, Jaime Fernando",
                title = "Energ{\'e}tica da zona de converg{\^e}ncia do Atl{\^a}ntico Sul 
                         (ZCAS)",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2020",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2020-02-14",
             keywords = "ZCAS, energia potencial dispon{\'{\i}}vel da 
                         perturba{\c{c}}{\~a}o, instabilidade barocl{\'{\i}}nica e 
                         barotr{\'o}pica, energia cin{\'e}tica da 
                         perturba{\c{c}}{\~a}o, SACZ, eddies's available potential 
                         energy, baroclinic and barotropic instability, eddies's kinetic 
                         energy.",
             abstract = "A energia do Sol que chega ao sistema Terra-atmosfera gera energia 
                         potencial que {\'e} convertida em outras formas de energias que 
                         est{\~a}o associadas {\`a}s intensidades das tempestades (EC) e 
                         finalmente dissipada pelo atrito e pelos v{\'o}rtices 
                         turbulentos. Durante este processo de gera{\c{c}}{\~a}o e 
                         convers{\~a}o de energia, sistemas como ZCAS podem se formar. As 
                         ZCAS s{\~a}o fen{\^o}menos atmosf{\'e}ricos de escala 
                         sin{\'o}tica com grande impacto social sobre a AS. Elas s{\~a}o 
                         caracterizadas por uma banda de nuvens e chuvas orientada NW-SE 
                         que se estende desde o centro sul/SE da amaz{\^o}nia ao 
                         Atl{\^a}ntico subtropical sul com dura{\c{c}}{\~a}o de 4 ou 
                         mais dias. O presente trabalho investiga a natureza 
                         energ{\'e}tica das ZCAS, as caracter{\'{\i}}sticas dos 
                         padr{\~o}es de localiza{\c{c}}{\~a}o (Norte-PN, Centro-PC e 
                         Sul-PS), os mecanismos da forma{\c{c}}{\~a}o, desenvolvimento e 
                         dissipa{\c{c}}{\~a}o. Para isso, utiliza-se a abordagem de Oort 
                         (1964) do ciclo da energia de Lorenz sob um dom{\'{\i}}nio 
                         misto. Por se tratar de um dom{\'{\i}}nio de {\'a}rea restrita, 
                         componentes de fluxos e dos mecanismos din{\^a}micos associados 
                         ao ciclo de energia s{\~a}o considerados. Foram utilizados dados 
                         de temperatura, vento e geopotencial da rean{\'a}lise ERA-5 no 
                         per{\'{\i}}odo de 01/10/1990 a 30/04/2018, que foi dividido em 
                         dois a fim de investigar poss{\'{\i}}veis mudan{\c{c}}as na 
                         frequ{\^e}ncia de ocorr{\^e}ncia, dura{\c{c}}{\~a}o e 
                         intensidade das ZCAS. As an{\'a}lises dos resultados revelam 
                         importantes caracter{\'{\i}}sticas do Ciclo da Energia de Loren 
                         (CEL) das ZCAS. Estes sugerem que, nas ZCAS a energia {\'e} 
                         gerada no estado b{\'a}sico de PM a uma taxa m{\'e}dia de 34,89 
                         Wm\−2 e que o resfriamento atrav{\'e}s das nuvens 
                         desfavorece a gera{\c{c}}{\~a}o de PE [G(PE)=-5,69 
                         Wm\−2]. As taxas de convers{\~o}es seguem o sentido de 
                         trocas de energia representados nos diagramas, exceto pela 
                         instabilidade barotr{\'o}pica observado durante os eventos de PN 
                         [C(KE,KM) < 0]. Uma an{\'a}lise detalhada baseada em 
                         sub{\'a}reas de atua{\c{c}}{\~a}o das ZCAS, revelou que a 
                         instabilidade barotr{\'o}pica domina nos tr{\'o}picos e no setor 
                         mais ao sul de sua atua{\c{c}}{\~a}o. Os componentes de energias 
                         m{\'e}dias zonais evidenciam a influ{\^e}ncia do baixo gradiente 
                         horizontal de temperatura nas ZCAS (com PM de 1,73 · 
                         105Jm\−2) e a grande predomin{\^a}ncia de KM (10,14 · 
                         105Jm\−2) atrav{\'e}s dos jatos subtropicais. As 
                         compara{\c{c}}{\~o}es dos resultados calculados para componentes 
                         de energias, mostraram que na m{\'e}dia o 2 per{\'{\i}}odo foi 
                         17,24% superior em rela{\c{c}}{\~a}o ao 1 e que, as energias 
                         calculadas para PN {\'e} 20,45% e 21% superior do que em PC e PS 
                         respectivamente. As se{\c{c}}{\~o}es verticais, revelaram que 
                         nos componentes de convers{\~o}es de energias as 
                         diferen{\c{c}}as s{\~a}o maiores em altos n{\'{\i}}veis nas 
                         c{\'e}lulas de circula{\c{c}}{\~a}o de Hadley e Ferrel. Por 
                         exemplo, os processos barotr{\'o}picos nestas c{\'e}lulas, 
                         s{\~a}o mais intensas durante PC e PS. Os resultados sugerem 
                         ainda a possibilidade de exist{\^e}ncia de uma pequena 
                         c{\'e}lula de circula{\c{c}}{\~a}o dentro da c{\'e}lula de 
                         Ferrel, que seria consistente para explicar o baixo consumo de 
                         energia observado na c{\'e}lula de Ferrel durante PN [C(PM,KM) < 
                         0]. Finalmente, conclu{\'{\i}}mos que as ZCAS s{\~a}o geradas e 
                         mantidas pela convec{\c{c}}{\~a}o tropical originadas 
                         atrav{\'e}s da maior disponibilidade de radia{\c{c}}{\~a}o 
                         solar e pela convec{\c{c}}{\~a}o ao sul proporcionadas pelos 
                         jatos subtropicais e v{\'o}rtice transientes de latitudes 
                         m{\'e}dias. ABSTRACT: The energy of the Sun arriving at the 
                         Earth-atmosphere system generates potential energy that is 
                         converted into other forms of energy that are associated with the 
                         intensities of the storms (KE) and finally dissipated by the 
                         friction and turbulent vortexes. During this process of energy 
                         generation and conversion, systems such as SACZ can form. The SACZ 
                         are synoptic scale atmospheric phenomena that has great social 
                         impact in AS. They are characterized by a band of clouds and 
                         rainfall oriented NW-SE that extends from the south/SE of the 
                         Amazon to the South subtropical Atlantic and persists for 4 or 
                         more days. Therefore, the present work investigates the energetic 
                         nature of the SACZ, the characteristics of the localization 
                         patterns (North, Center and South), the mechanisms of formation, 
                         development and dissipation. For this, we used the Lorenz energy 
                         cycle formulation following the Oort (1964) approach under a mixed 
                         domain. As it is a restricted area domain, components of flows and 
                         dynamic mechanisms associated with the energy cycle are 
                         considered. ERA-5 new generation reanalysis temperature, wind and 
                         geopotential data were used. The study period is from 01/10/1990 
                         to 04/30/2018 (taking into account the dates of occurrence of the 
                         SACZ episodes occurrence), which was divided into two periods 
                         (from 01/10/1990 to 31/12/2005 and 01/01/2006 to 04/30/2018) to 
                         investigate possible changes in frequency of occurrence, duration 
                         and intensity of the SACZ. The results analysis reveal important 
                         Lorenz Energy Cycle (LEC) SACZ characteristics. These suggests 
                         that SACZ energy is generated in PM basic state at a mean rate of 
                         34,89 Wm\−2 and the cooling throughout the clouds works 
                         against the PE [G(PE)=-5,69Wm\−2] generation. The 
                         conversion rate follow the energies exchanges presented in the 
                         diagrams, except the barotropic instability observed during PN 
                         events [C(KE,KM)<0]. A detailed analysis based in subareas of SACZ 
                         actuation, revealed that barotropic instability is dominant at 
                         tropics and at the southernmost sector of its actuation. The zonal 
                         average energy components shows the influence of the low 
                         horizontal temperature gradient over SACZ (with PM equivalent to 
                         1,73·105Jm\−2) and the great predominance of KM 
                         (10,14·105Jm\−2) due to subtropical jets. Energy components 
                         results comparisons, shows that on average the 2nd period was 
                         17,24% superior in relation to the 1st and that calculated 
                         energies to PN is 20,45% and 21% superior than to PN and PS, 
                         respectively. The vertical cross sections, revealed that the 
                         energy conversions components differences are bigger at high 
                         levels at Hadleys and Ferrels circulation cells. For example, the 
                         barotropic processes at Hadleys and Ferrels circulation cells over 
                         SA is more intense during PC and PS. The results also suggests the 
                         possibility of the existence of a small cell inside Ferrels cell, 
                         which would be consistent to explain the low energy consumption 
                         observed at Ferrels cell during PN [C(PM,KM)<0]. Therefore, SACZ 
                         are generated and maintained by tropical convection caused by 
                         higher solar radiation availability and by southward convection 
                         due to subtropical jets and mid-latitudes transient eddies.",
            committee = "Herdies, Dirceu Luis (presidente) and Arav{\'e}quia, Jos{\'e} 
                         Antonio (orientador) and Bonatti, Jos{\'e} Paulo and Quadro, 
                         Mario Francisco Leal de",
         englishtitle = "Energy of the South Atlantic convergence zone (SACZ)",
             language = "pt",
                pages = "148",
                  ibi = "8JMKD3MGP3W34R/3UU4TL8",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3UU4TL8",
           targetfile = "publicacao.pdf",
        urlaccessdate = "2021, Mar. 05"
}


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