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@PhDThesis{Ferreira:2013:VaMoAm,
               author = "Ferreira, Solange Arag{\~a}o",
                title = "Variabilidade da mon{\c{c}}{\~a}o da Am{\'e}rica do Sul",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2013",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2013-02-28",
             keywords = "variabilidade, Am{\'e}rica do Sul, precipita{\c{c}}{\~a}o, 
                         mon{\c{c}}{\~a}o, variability, South America, monsoon, 
                         preciptation.",
             abstract = "Os per{\'{\i}}odos ativos e inativos do Sistema de 
                         Mon{\c{c}}{\~a}o da Am{\'e}rica Sul (SMAS) foram determinados 
                         com base no {\'{\I}}ndice de Precipita{\c{c}}{\~a}o da 
                         Mon{\c{c}}{\~a}o (IPM) para os tr{\^e}s meses mais {\'u}midos 
                         (DJF). O campo do composto da precipita{\c{c}}{\~a}o para os 
                         casos de per{\'{\i}}odos ativos mostra um padr{\~a}o semelhante 
                         {\`a} precipita{\c{c}}{\~a}o m{\'e}dia de ver{\~a}o. O 
                         composto da circula{\c{c}}{\~a}o dos ventos apresenta um forte 
                         fluxo de noroeste desde o oeste da Amaz{\^o}nia at{\'e} o 
                         sudeste do Brasil. Durante per{\'{\i}}odos ativos (inativos), 
                         uma intensa (fraca) converg{\^e}ncia do fluxo de umidade ocorre 
                         ao longo da bacia amaz{\^o}nica, sudeste e centro-oeste do 
                         Brasil. A intensa converg{\^e}ncia de umidade sobre essas 
                         regi{\~o}es durante os per{\'{\i}}odos ativos {\'e} uma 
                         caracter{\'{\i}}stica t{\'{\i}}pica da Zona de 
                         Converg{\^e}ncia do Atl{\^a}ntico Sul (ZCAS). Diagramas de 
                         Hovm{\"o}ller nas p{\^e}ntadas de ROL, assim como anomalias de 
                         ROL n{\~a}o filtradas e filtradas com m{\'e}dia entre as 
                         latitudes de 0\$°\$ e 10\$°\$S, foram utilizados para 
                         identificar associa{\c{c}}{\~o}es da presen{\c{c}}a ou 
                         aus{\^e}ncia de nebulosidade convectiva com as ondas de Kelvin e 
                         de Rossby equatorial, e a OMJ. Uma oscila{\c{c}}{\~a}o da 
                         convec{\c{c}}{\~a}o na ordem de 10 a 15 dias que foi associada 
                         {\`a} variabilidade da intensidade do anticiclone boliviano, e 
                         outra oscila{\c{c}}{\~a}o associada {\`a} presen{\c{c}}a de 
                         VCANs sobre o Nordeste do Brasil, tamb{\'e}m foram observadas. As 
                         an{\'a}lises da convec{\c{c}}{\~a}o mostraram que na maioria 
                         dos casos a convec{\c{c}}{\~a}o com propaga{\c{c}}{\~a}o para 
                         leste esteve associada {\`a}s ondas de Kelvin. As atividades 
                         convectivas com deslocamento para oeste estiveram associadas 
                         {\`a}s ondas de Rossby. Neste trabalho observou-se as ondas 
                         equatoriais de Rossby e Kelvin interagindo com a 
                         convec{\c{c}}{\~a}o, resultando em deslocamento e 
                         intensifica{\c{c}}{\~a}o da atividade convectiva. A fase 
                         favor{\'a}vel {\`a} convec{\c{c}}{\~a}o da OMJ interagiu com 
                         as ondas equatoriais de Kelvin e de Rossby, e tamb{\'e}m 
                         contribuiu para intensificar a convec{\c{c}}{\~a}o. A 
                         an{\'a}lise da EOF Ciclo Estacion{\'a}ria (CSEOF) foi aplicada 
                         sobre a regi{\~a}o entre 20\$°\$N-60\$°\$S e 
                         0\$°\$-90\$°\$E durante 29 anos, e para diferentes 
                         vari{\'a}veis considerando as 30 primeiras CSEOF. Neste estudo 
                         foram analisados os 3 primeiros modos da CSEOF, onde juntos 
                         explicam um total de variabilidade entre 18 e 70 \%. O primeiro 
                         modo da CSEOF representa o padr{\~a}o ciclo sazonal, o segundo 
                         modo explica a fase fria do ENOS (La Niņa) sobre o Oceano 
                         Pac{\'{\i}}fico Tropical, e o terceiro modo descreve a fase de 
                         transi{\c{c}}{\~a}o do ENOS (de La Niņa para El Niņo) e 
                         poss{\'{\i}}vel atua{\c{c}}{\~a}o da OMJ. Esses padr{\~o}es 
                         mostram uma configura{\c{c}}{\~a}o de propaga{\c{c}}{\~a}o de 
                         trens de onda entre as regi{\~o}es 
                         Indon{\'e}sia/Pac{\'{\i}}fico e Am{\'e}rica do Sul, que 
                         s{\~a}o associados {\`a} intensifica{\c{c}}{\~a}o ou 
                         enfraquecimento da atividade convectiva sobre a regi{\~a}o de 
                         atua{\c{c}}{\~a}o da ZCAS, e regi{\~a}o do SMAS. ABSTRACT: The 
                         active and break periods of the South America monsoon system 
                         (SAMS) were determined based on a monsoon rainfall index (MRI) for 
                         the three wettest months. The precipitation composite for active 
                         cases shows a pattern similar to the average summer rainfall. The 
                         wind circulation composite presents a strong northwesterly flow 
                         from the western Amazon to southeastern Brazil. During active 
                         (break) periods, an intense (weak) moisture flux convergence 
                         occurs over the Amazon Basin, southeastern and central-western 
                         Brazil. The intense moisture convergence over these regions during 
                         the active periods is a typical feature of the South Atlantic 
                         Convergence Zone (SACZ) system. Hovm{\"o}ller diagrams of OLR 
                         pentads, OLR anomalies as well unfiltered and filtered mean 
                         between latitudes 0\$°\$ and 10\$°\$S, were used to identify 
                         associations of the presence or suppression of convective 
                         cloudiness with Kelvin and Rossby equatorial waves, and 
                         Madden-Julian oscillation (MJO). An oscillation of convection in 
                         the order of 10 to 15 days was associated with variability in the 
                         intensity of the Bolivian anticyclone, and other oscillation 
                         associated with the presence of VCANs over northeastern Brazil, 
                         were also observed. The analysis showed that the convection with 
                         eastward displacing was associated with Kelvin waves in most of 
                         the cases. Convective activities with westward displacement were 
                         associated with Rossby waves. In this work was observed the 
                         equatorial Rossby and Kelvin interacting with convection, 
                         resulting in displacement and intensification of convective 
                         activity. The favorable phase to MJO convection interacted with 
                         equatorial Rossby and Kelvin waves, and also contributed to 
                         enhance convection. The favorable phase to convection of the MJO 
                         interacted with the equatorial Kelvin waves, and contributed to 
                         intensify the convection. Cyclostationary Empirical Orthogonal 
                         Function (CSEOF) analysis was applied in the region between 
                         20\$°\$N-60\$°\$S and 0\$°\$-90\$°\$E and for 29 years, 
                         for several variables and considering the first 30 CSEOF. This 
                         study were analyzed only the 3 first modes of CSEOF, which 
                         together explain a total variability around 18 and 70\%. The 
                         first mode represents the CSEOF seasonal cycle, the second mode 
                         explains the cold phase of ENSO (La Niņa), and the third mode 
                         describes the transition phase of ENSO (La Niņa to El Niņo) and 
                         possible interaction of the Madden Julian Oscillation. These 
                         patterns show a configuration propagating wave trains between 
                         regions Indonesia / Pacific and South America, which are 
                         associated with the intensification or weakening of convective 
                         activity over the SACZ and the SAMS regions.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)}",
            committee = "Ferreira, Nelson Jesuz (presidente) and Gan, Manoel Alonso 
                         (orientador) and Cavalcanti, Iracema Fonseca de Albuquerque and 
                         Ambrizzi, T{\'e}rcio and Silva, Adma Raia",
           copyholder = "SID/SCD",
         englishtitle = "Variability of the South America Monsoon",
             language = "pt",
                pages = "207",
                  ibi = "8JMKD3MGP7W/3DSAUJ2",
                  url = "http://urlib.net/rep/8JMKD3MGP7W/3DSAUJ2",
           targetfile = "publicacao.pdf",
        urlaccessdate = "19 jan. 2021"
}


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