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@MastersThesis{Gomes:2018:AnPaAt,
               author = "Gomes, Mariah Sousa",
                title = "An{\'a}lise dos padr{\~o}es atmosf{\'e}ricos associados a 
                         eventos secos na bacia Amaz{\^o}nia",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2018",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2018-05-25",
             keywords = "Seca, bacia Amaz{\^o}nica, circula{\c{c}}{\~a}o 
                         atmosf{\'e}rica, rean{\'a}lise CFSR, sat{\'e}lite TRMM, 
                         drought, Amazon basin, atmospheric circulation, reanalysis CFSR, 
                         satellite TRMM.",
             abstract = "Secas s{\~a}o eventos meteorol{\'o}gicos capazes de causar 
                         graves transtornos socioecon{\^o}micos. Embora sua 
                         defini{\c{c}}{\~a}o varie de acordo com o clima da localidade 
                         afetada e finalidade do estudo, s{\~a}o caracterizadas por um 
                         d{\'e}ficit h{\'{\i}}drico como consequ{\^e}ncia de um 
                         prolongado per{\'{\i}}odo de chuvas inferiores a m{\'e}dia na 
                         {\'a}rea em quest{\~a}o. Na Amaz{\^o}nia, encontra-se a maior 
                         floresta tropical e bacia hidrogr{\'a}fica do mundo, o que faz 
                         dela um bioma de caracter{\'{\i}}sticas peculiares. O ENOS e 
                         aquecimento an{\^o}malo da superf{\'{\i}}cie do ATN impactam 
                         nas condi{\c{c}}{\~o}es atmosf{\'e}ricas da regi{\~a}o, e 
                         consequentemente na variabilidade do seu regime de chuvas. 
                         Recentes estudos investigaram a rela{\c{c}}{\~a}o entre tais 
                         fen{\^o}menos e as secas de 1997-1998, 2005 e 2010, no entanto 
                         alguns aspectos destes epis{\'o}dios ainda n{\~a}o foram 
                         esclarecidos, como as caracter{\'{\i}}sticas da 
                         circula{\c{c}}{\~a}o m{\'e}dia durante os eventos. O presente 
                         estudo tem por objetivos caracterizar os eventos de 1997-1998, 
                         2005 e 2010, identificar a influ{\^e}ncia remota das anomalias de 
                         TSM mencionadas e padr{\~o}es atmosf{\'e}ricos associados, em 
                         espec{\'{\i}}fico as circula{\c{c}}{\~o}es de Hadley e Walker. 
                         Os resultados encontrados permitiram identificar que padr{\~o}es 
                         de circula{\c{c}}{\~a}o zonal an{\^o}malos foram determinantes 
                         para a ocorr{\^e}ncia do evento seco de 1997-1998 uma vez que 
                         houve uma invers{\~a}o da posi{\c{c}}{\~a}o dos ramos 
                         ascendentes e subsidentes da c{\'e}lula de Walker. A componente 
                         meridional tamb{\'e}m determinou as altera{\c{c}}{\~o}es no 
                         regime de chuvas, e suas anomalias provavelmente estiveram 
                         associadas ao enfraquecimento dos ventos Al{\'{\i}}sios. As 
                         condi{\c{c}}{\~o}es secas que culminaram no evento de 2005 foram 
                         determinadas, em sua maior parte, pelas anomalias de 
                         circula{\c{c}}{\~a}o meridional de Hadley, com ramo ascendente 
                         deslocado para nordeste. As anomalias sazonais de 
                         precipita{\c{c}}{\~a}o na bacia Amaz{\^o}nica persistiram 
                         principalmente durante a esta{\c{c}}{\~a}o seca de 2004 e 2005, 
                         no entanto observou-se intensas anomalias positivas de movimento 
                         vertical sobre o ATN na esta{\c{c}}{\~a}o chuvosa. J{\'a} o 
                         evento de 2010 foi determinado por mudan{\c{c}}as no 
                         comportamento da circula{\c{c}}{\~a}o zonal, durante o 
                         ver{\~a}o, quando o El Niņo atuou, e tamb{\'e}m na 
                         circula{\c{c}}{\~a}o meridional, principalmente devido as 
                         anomalias de TSM no ATN. Sua severidade p{\^o}de ser 
                         atribu{\'{\i}}da {\`a} atua{\c{c}}{\~a}o simult{\^a}nea 
                         destes padr{\~o}es at{\'{\i}}picos, e a persist{\^e}ncia de 
                         intensos movimentos ascendentes no oceano durante a 
                         esta{\c{c}}{\~a}o seca. Dos resultados encontrados {\'e} 
                         poss{\'{\i}}vel concluir portanto, que eventos secos na 
                         Amaz{\^o}nia est{\~a}o diretamente relacionados a 
                         mudan{\c{c}}as nos padr{\~o}es de escoamento em baixos e 
                         m{\'e}dios n{\'{\i}}veis, assim como modifica{\c{c}}{\~o}es 
                         na circula{\c{c}}{\~a}o zonal e meriodional. ABSTRACT: Droughts 
                         are meteorological events capable of causing severe socioeconomic 
                         disturbances, and although their definition may vary according to 
                         the purpose of the studies involved and the climate of the 
                         affected regions, they may be characterized by a water deficit 
                         because of below-expected rainfall. In Amazon there is a largest 
                         tropical rainforest and watershed in the world, making it a biome 
                         of peculiar characteristics. It is known that the El Niņo-Southern 
                         Oscillation and the anomalous heating of the surface of the North 
                         Atlantic Ocean directly impact on the atmospheric conditions of 
                         this region, and projections indicate a possible increase in the 
                         frequency and severity of these episodes, associated to such 
                         phenomena. Although some studies have recently analyzed their 
                         causes and impacts, some aspects of the 1997-98, 2005-06 and 2010 
                         droughts are still not well understood, as the characteristics of 
                         the average circulation during the events. The objective of this 
                         study is therefore to identify how the 1997-1998, 2005 and 2010 
                         events teleconnections affected the atmospheric circulation of the 
                         Amazon region during periods of drought, specifically the Haddley 
                         and Walker circulations. The results showed that anomalous zonal 
                         circulation patterns were determinant for the occurrence of the 
                         dry event of 1997-1998 since there was an inversion of the 
                         position of the ascending branches and subsidence of the Walker 
                         cell. The meridional component also determined the changes in the 
                         rainfall regime, and its anomalies were probably associated with 
                         the weakening of the Al{\'{\i}}sios winds. The dry conditions 
                         that culminated in the 2005 event were determined, for the most 
                         part, by Hadley's meridional circulation anomalies, with an upward 
                         branch moving to the northeast. Precipitation anomalies in the 
                         Amazon basin persisted mainly during the dry season of 2004 and 
                         2005, however intense positive anomalies of vertical movement on 
                         the ATN were observed in the rainy season. The event of 2010 was 
                         determined by changes in the behavior of the zonal circulation, 
                         during the summer, when the El Niņo played, and also in the 
                         meridional circulation, mainly due to the SST anomalies in the 
                         ATN. Its severity could be attributed to the simultaneous 
                         performance of these atypical patterns, and the persistence of 
                         intense upward movements in the ocean during the dry season. From 
                         the results it is possible to conclude that dry events in the 
                         Amazon are directly related to changes in flow patterns at low and 
                         medium levels, as well as changes in zonal and meriodional 
                         circulation.",
            committee = "Arav{\'e}quia, Jos{\'e} Antonio (Presidente) and Herdies, Dirceu 
                         Luis (Orientador) and Souza, Diego Oliveira de (Orientador) and 
                         Quadro, Mario Francisco Leal de and M{\"u}ller, Gabriela 
                         Viviana",
         englishtitle = "Analysis of atmospheric patterns associated to dry events in the 
                         Amazon basin",
             language = "pt",
                pages = "136",
                  ibi = "8JMKD3MGP3W34R/3R6QKJH",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3R6QKJH",
           targetfile = "publicacao.pdf",
        urlaccessdate = "05 dez. 2020"
}


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