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@PhDThesis{Fernandes:2018:InEsVa,
               author = "Fernandes, Valesca Rodriguez",
                title = "Influ{\^e}ncia das escalas de variabilidade sin{\'o}tica, 
                         submensal e intrassazonal nas regi{\~o}es tropicais e 
                         subtropicais da Am{\'e}rica do Sul e oceanos adjacentes",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2018-05-24",
             keywords = "intera{\c{c}}{\~a}o de escalas, intrasazonal, sin{\'o}tica, 
                         submensal, Am{\'e}rica do Sul, Sudeste do Brasil, scales 
                         interaction, intraseasonal, synoptic, submonthly, South America, 
                         Southeastern Brazil.",
             abstract = "No intuito de identificar os modos dominantes de variabilidade da 
                         atividade convectiva que atuam nas regi{\~o}es extratropicais e 
                         tropicais da Am{\'e}rica do Sul (AS) e os oceanos adjacentes, 
                         utilizaram-se dois m{\'e}todos de an{\'a}lise: a Transformada de 
                         Ondaletas (TO) e Padr{\~a}o de Oscila{\c{c}}{\~a}o Principal 
                         (POP). Os dados di{\'a}rios de radia{\c{c}}{\~a}o de onda longa 
                         (ROL) foram utilizados como proxies de convec{\c{c}}{\~a}o e 
                         referem-se ao per{\'{\i}}odo de 1979 a 2016. A TO foi aplicada 
                         na s{\'e}rie temporal de ROL com intuito de obter a pot{\^e}ncia 
                         espectral (vari{\^a}ncias) nas escalas sin{\'o}tica, submensal e 
                         intrassazonal. Na escala sin{\'o}tica, observou-se 
                         vari{\^a}ncias mais significativas sobre a regi{\~a}o tropical 
                         associada {\`a} Zona de Converg{\^e}ncia Intertropical (ZCIT), 
                         na regi{\~a}o Sul da AS associadas aos sistemas frontais e ao 
                         longo de regi{\~o}es dominadas por sistemas transientes. Na 
                         escala submensal, observaram-se maiores valores de vari{\^a}ncia 
                         nas regi{\~o}es Centro-oeste e Sudeste do Brasil associado {\`a} 
                         Zona de Converg{\^e}ncia do Atl{\^a}ntico Sul (ZCAS) e, 
                         tamb{\'e}m se observa no Oceano Pac{\'{\i}}fico Oeste, Central 
                         e nordeste da Austr{\'a}lia devido {\`a} atua{\c{c}}{\~a}o da 
                         Zona de Converg{\^e}ncia do Pac{\'{\i}}fico Sul (ZCPS). Na 
                         escala intrassazonal, os maiores valores de vari{\^a}ncia foram 
                         observados no oceano Pac{\'{\i}}fico e na regi{\~a}o Sudeste e 
                         Nordeste da Am{\'e}rica do Sul que podem estar associados {\`a} 
                         presen{\c{c}}a da Oscila{\c{c}}{\~a}o de Madden Julian (OMJ). A 
                         fim de investigar os modos dominantes nas escalas de 10-30 e 30-60 
                         dias sobre a AS e oceanos adjacentes utilizou o m{\'e}todo POP no 
                         per{\'{\i}}odo de ver{\~a}o austral de 2006 a 2016. Os 
                         resultados para a escala submensal mostram que o modo mais 
                         significativo apresenta vari{\^a}ncia de 17,7%. Esse modo {\'e} 
                         caracterizado por um trem de ondas, que se propagam do 
                         Pac{\'{\i}}fico na dire{\c{c}}{\~a}o leste e associa-se a ZCAS 
                         intensificada (suprimida) com supress{\~a}o 
                         (intensifica{\c{c}}{\~a}o) da convec{\c{c}}{\~a}o sobre o Sul 
                         do Brasil. Na escala intrassazonal, a vari{\^a}ncia foi de 19,5% 
                         e observa-se padr{\~a}o oscilat{\'o}rio de onda na regi{\~a}o 
                         do oceano Pac{\'{\i}}fico Leste com propaga{\c{c}}ao para a 
                         regi{\~a}o Sudeste e Nordeste do Brasil. A fim de avaliar os 
                         padr{\~o}es de circula{\c{c}}{\~a}o atmosf{\'e}rica em baixos 
                         e altos n{\'{\i}}veis e ROL foram feitos compostos associados ao 
                         modo dominante do v300/POP. Na escala submensal, observou-se um 
                         dipolo entre a regi{\~a}o da ZCAS (associada a maior 
                         precipita{\c{c}}{\~a}o) e sul do Brasil (associada a menos 
                         precipita{\c{c}}{\~a}o). Na anomalia do vento (altos 
                         n{\'{\i}}veis) destacou-se um padr{\~a}o ondulat{\'o}rio do 
                         oceano Pac{\'{\i}}fico Sul para a AS. Na evolu{\c{c}}{\~a}o 
                         desse padr{\~a}o, pode-se verificar a varia{\c{c}}{\~a}o na 
                         amplitude dos m{\'a}ximos, o que indica propaga{\c{c}}{\~a}o de 
                         energia. No campo m{\'e}dio e anomalia do vento (baixos 
                         n{\'{\i}}veis) observou-se a presen{\c{c}}a dos sistemas 
                         transientes, as altas ASAS e ASPS, circula{\c{c}}{\~a}o do JBN e 
                         converg{\^e}ncia dos ventos associados {\`a} ZCAS, 
                         respectivamente. Na escala intrassazonal, a composi{\c{c}}{\~a}o 
                         do vento (300 hPa) {\'e} similar {\`a} escala submensal, 
                         por{\'e}m diferem na posi{\c{c}}{\~a}o e intensidade dos 
                         sistemas. Na composi{\c{c}}{\~a}o de ROL observou-se 
                         convec{\c{c}}{\~a}o ativa na regi{\~a}o Sudeste do Brasil, 
                         associada {\`a} ZCAS e, tamb{\'e}m, a presen{\c{c}}a da OMJ. 
                         Foram feitas an{\'a}lises da energia cin{\'e}tica (EC) para a 
                         AS, com intuito de analisar poss{\'{\i}}veis 
                         intera{\c{c}}{\~o}es entre os eddies de diferentes escalas de 
                         tempo. Resultados encontrados mostraram que a 
                         distribui{\c{c}}{\~a}o de EC na escala sin{\'o}tica 
                         concentra-se essencialmente em latitudes m{\'e}dias e altas ao 
                         longo das storm tracks. A fonte de energia nessas latitudes 
                         origina-se principalmente da convers{\~a}o barocl{\'{\i}}nica. 
                         Para a escala submensal, a distribui{\c{c}}{\~a}o de EC 
                         concentra-se principalmente no Pac{\'{\i}}fico Sul a oeste dos 
                         Andes. O sinal forte de EC nessa regi{\~a}o {\'e} dominado pela 
                         converg{\^e}ncia do fluxo de energia. Na faixa dos storm tracks 
                         (entre 40 a 50 S) a EC na escala x submensal assemelha-se com o 
                         padr{\~a}o dessa vari{\'a}vel na escala sin{\'o}tica, sendo 
                         dominado pelo termo de convers{\~a}o barocl{\'{\i}}nica dessa 
                         escala. A distribui{\c{c}}{\~a}o de EC no Pac{\'{\i}}fico Sul 
                         para a escala intrassazonal n{\~a}o apresenta um padr{\~a}o bem 
                         definido, ela {\'e} caracterizada por sinais positivos e 
                         negativos. Por outro lado, no sul da AS e oceanos vizinhos 
                         destaca-se sinais positivos a oeste dos Andes e negativos no 
                         Atl{\^a}ntico Sudoeste. Essa configura{\c{c}}{\~a}o 
                         assemelha-se aos campos da convers{\~a}o barocl{\'{\i}}nica e 
                         barotr{\'o}pica, mas com sinais opostos. Assim EC intrassazonal 
                         {\'e} dominada pelo termo de convers{\~a}o do fluxo de energia 
                         que {\'e} forte nessa regi{\~a}o. Desta forma, conclui-se que 
                         h{\'a} intera{\c{c}}{\~a}o de escalas na Am{\'e}rica do Sul e 
                         oceanos adjacentes, por{\'e}m a escala submensal apresenta uma 
                         amplitude maior que as escalas sin{\'o}tica e intrassazonal na 
                         regi{\~a}o sudeste do Brasil. ABSTRACT: In order to identify the 
                         dominant modes of convective activity variability that act in the 
                         extratropics and tropics regions of South America (SA) and the 
                         adjacent oceans, two methods of analysis were used: the Wavelet 
                         Transform (TO) and the Principal Oscillation Pattern (POP). The 
                         daily outgoing longwave radiation (OLR) were used as convection 
                         proxies and refer to the period 1979 to 2016. The TO was applied 
                         in the time series of ROL in order to obtain the global power 
                         spectrum (variance) of synoptic, submonthly and intraseasonal 
                         scales. In the synoptic scale, the wavelet transform showed the 
                         most significant variances on the tropical region associated to 
                         the Intertropical Convergence Zone (ITCZ), in the southern region 
                         of the SA associated with the frontal systems and along regions 
                         dominated by transient systems. In the submonthly scale, the 
                         highest values of variance in the central-west and south-eastern 
                         regions of Brazil associated with the South Atlantic Convergence 
                         Zone (SACZ) were observed, and it is also observed in the Western 
                         Pacific Ocean, Central and Northeastern Australia due to of the 
                         South Pacific Convergence Zone (SPCZ). In the intraseasonal scale, 
                         the highest values of variance were observed in the Pacific Ocean 
                         and in the Southeast and Northeast region of South America that 
                         may be associated with the presence of Madden Julian Oscillation 
                         (MJO). In order to investigate dominant modes at the 10-30 and 
                         30-60 day scales on AS and adjacent oceans used the POP method in 
                         the austral summer period from 2006 to 2016. In the submonthly 
                         scale, the most significant variability mode presents a variance 
                         of 17.1%. These modes are characterized by wave patterns that 
                         propagate from the Pacific in the eastward direction and this wave 
                         pattern seems to associate an intensified (suppressed) SACZ with 
                         suppression (intensification) of convection over southern Brazil. 
                         In the intraseasonal scale, the observed variance was 19.5% and 
                         the same oscillatory wave pattern is observed in the region of the 
                         Eastern Pacific Ocean with propagation to the southeastern and 
                         northeastern region of Brazil. In order to evaluate atmospheric 
                         circulation patterns at low and high levels and OLR, composite 
                         fields associated with the dominant mode of v300 / POP were made. 
                         In the submonthly scale, a dipole was observed between the SACZ 
                         region (associated to the highest precipitation) and southern 
                         Brazil (associated with less precipitation). In the anomaly of the 
                         wind (high levels) we highlighted a wave pattern of the South 
                         Pacific Ocean for AS. In the evolution of this pattern, one can 
                         verify the variation in the amplitude of the maxima, which 
                         indicates propagation of energy. In the mean field and wind 
                         anomaly (low levels) the presence of transient systems, the ASAS 
                         and ASPS highs, the low level jet circulation (LLJ) and the 
                         convergence of the winds associated to the SACZ, respectively, 
                         were observed. In the intraseasonal scale, the composition of the 
                         wind (300 hPa) is similar to the submonthly scale, but they differ 
                         in the position and intensity of the systems. In the OLR 
                         composition, active convection was observed in the southeastern 
                         region of Brazil, xii associated to the SACZ and also the presence 
                         of the MJO. Kinetic energy balance was analyzed for South America 
                         in order to analyze possible interactions between eddies of 
                         different time scales. Results showed that the EC distribution in 
                         the synoptic scale is mainly concentrated in mid and high 
                         latitudes along the storm tracks. The source of energy in these 
                         latitudes comes mainly from the baroclinic conversion. For the 
                         submonthly scale, the EC distribution is mainly concentrated in 
                         the South Pacific west of the Andes. The strong EC signal in this 
                         region is dominated by the energy flux convergence. In the band of 
                         storm tracks (between 40 and 50 S) the EC on the submonthly 
                         scale resembles the standard of this variable in high frequency, 
                         being dominated by the baroclinic conversion term of this scale. 
                         Finally, the distribution of EC in the South Pacific to the 
                         intrastate scale does not present a well-defined pattern, it is 
                         characterized by positive and negative signals. On the other hand, 
                         in the south of the AS and neighboring oceans there are positive 
                         signs to the west of the Andes and negatives in the Southwest 
                         Atlantic. This configuration resembles the baroclinic and 
                         barotropic conversion fields, but with opposing signs. Thus 
                         intraseasonal EC is dominated by the energy flow conversion term 
                         that is strong in that region. In this way, it is concluded that 
                         there is interaction of scales in South America and adjacent 
                         oceans, but the submonthly scale has a greater amplitude than the 
                         synoptic and intreseasonal scales in the southeastern region of 
                         Brazil.",
            committee = "Gan, Manoel Alonso (presidente) and Ferreira, Nelson Jesuz 
                         (orientador) and M{\"u}ller, Gabriela Viviana (orientadora) and 
                         Escobar, Gustavo Carlos Juan and Brambila, Mar{\'{\i}}a 
                         Cleof{\'e} Valverde and Corr{\^e}a, Cleber Souza",
         englishtitle = "Influence of synoptic, submonthly and intraseasonal variability 
                         scales in the tropical and subtropical regions of South America 
                         and adjacent oceans",
             language = "pt",
                pages = "174",
                  ibi = "8JMKD3MGP3W34R/3QLRDCP",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3QLRDCP",
           targetfile = "publicacao.pdf",
        urlaccessdate = "05 dez. 2020"
}


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