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@MastersThesis{Gurjão:2017:InCoEl,
               author = "Gurj{\~a}o, Carlos Diego de Sousa",
                title = "Influ{\^e}ncia conjunta do El Niņo-oscila{\c{c}}{\~a}o sul e 
                         dipolo da Ant{\'a}rtica no gelo marinho dos mares de 
                         Bellingshausen-Amundsen e no mar de Weddell",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2017",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2017-08-04",
             keywords = "dipolo da Ant{\'a}rtica. El Niņo-oscila{\c{c}}{\~a}o sul. gelo 
                         marinho. teleconex{\~o}es. Antarctic dipole. ENSO. sea ice. 
                         teleconnections.",
             abstract = "O Dipolo da Ant{\'a}rtica (DPA) {\'e} um modo de variabilidade 
                         clim{\'a}tica observado em in{\'u}meras vari{\'a}veis 
                         atmosf{\'e}ricas entre os setores do Atl{\^a}ntico e 
                         Pac{\'{\i}}fico do Oceano Austral. O entendimento do DPA tem 
                         ajudado na compreens{\~a}o dos mecanismos de teleconex{\~o}es 
                         entre o Pac{\'{\i}}fico Equatorial Central e os diferentes 
                         setores do Oceano Austral. Existem v{\'a}rios estudos na 
                         literatura que sugerem algum tipo de teleconex{\~a}o entre os 
                         campos de Gelo Marinho (GM) e o clima global. Com base nesta 
                         hip{\'o}tese, este trabalho pretende analisar se o padr{\~a}o 
                         DPA se manifesta no campo de anomalias sazonais de 
                         Concentra{\c{c}}{\~a}o de Gelo Marinho (CGM) e de vari{\'a}veis 
                         atmosf{\'e}ricas de duas bases de dados de rean{\'a}lises atuais 
                         durante eventos extremos do El Niņo Oscila{\c{c}}{\~a}o Sul 
                         (ENOS). A segunda etapa visa avaliar os principais modos de 
                         variabilidade sazonal do campo de CGM e dos campos 
                         atmosf{\'e}ricos adjacentes, isto {\'e}, Press{\~a}o ao 
                         N{\'{\i}}vel M{\'e}dio do Mar (PNMM) e Temperatura do Ar em 
                         Superf{\'{\i}}cie (TAS). O estudo compreende o per{\'{\i}}odo 
                         entre os anos de 1979 e 2014. A liga{\c{c}}{\~a}o entre as 
                         vari{\'a}veis atmosf{\'e}ricas e GM durante o evento ENOS 
                         decorre em uma persist{\^e}ncia de anomalias de GM configurando 
                         um padr{\~a}o DPA confinado entre os setores do Atl{\^a}ntico e 
                         Pac{\'{\i}}fico do Oceano Austral. Em todas as 
                         composi{\c{c}}{\~o}es verificou-se que o padr{\~a}o DPA {\'e} 
                         bem mais definido nos compostos da CGM, no inverno e na primavera. 
                         A influ{\^e}ncia do DPA na variabilidade do GM, assim como na 
                         atmosfera, n{\~a}o foi detectada no ver{\~a}o austral. Outro 
                         ponto de discuss{\~a}o {\'e} a natureza do deslocamento dos 
                         centros de anomalias positivas e negativas da PNMM, durante 
                         eventos de El Niņo. Verificou-se que a localiza{\c{c}}{\~a}o dos 
                         centros de anomalias n{\~a}o coincidiam com as regi{\~o}es do 
                         Atl{\^a}ntico e Pac{\'{\i}}fico do Oceano Austral; um centro de 
                         anomalia positiva centrado na Passagem de Drake {\'e} um exemplo. 
                         Atrav{\'e}s dos campos de anomalias de Altura do Geopotencial 
                         (AGP), verificou-se que os padr{\~o}es cicl{\^o}nicos e 
                         anticicl{\^o}nicos que est{\~a}o confinados entre os setores do 
                         Oceano Austral mantiveramse com a mesma estrutura vertical em toda 
                         a sua profundidade, indicando que o sinal atmosf{\'e}rico {\'e} 
                         basicamente barotr{\'o}pico. A an{\'a}lise das 
                         Fun{\c{c}}{\~o}es Ortogonais Emp{\'{\i}}ricas (FOEs) mostra 
                         que os primeiros modos de variabilidade da CGM, do ver{\~a}o 
                         (DJF) e outono (MAM), no Oceano Austral, apresentam 
                         frequ{\^e}ncia interanual. No entanto, os principais modos do 
                         gelo marinho no inverno (JJA) e primavera (SON) apresentam o 
                         padr{\~a}o DPA e est{\~a}o associados {\`a} influ{\^e}ncia do 
                         ENOS. Os primeiros modos das FOEs associados {\`a} PNMM, em todas 
                         as esta{\c{c}}{\~o}es revelam caracter{\'{\i}}sticas da 
                         Oscila{\c{c}}{\~a}o Ant{\'a}rtica (OA). No geral, este trabalho 
                         cumpriu o objetivo de verificar as respostas da influ{\^e}ncia do 
                         ENOS {\`a}s anomalias do campo atmosf{\'e}rico e impactos 
                         associados no gelo marinho, em escala interanual. ABSTRACT: The 
                         Antarctic Dipole (ADP) is a mode of climatic variability observed 
                         in several atmospheric variables between the Atlantic and Pacific 
                         sectors of the Southern Ocean. The understanding of ADP has helped 
                         in understanding the teleconnection mechanisms between the Central 
                         Equatorial Pacific and the different sectors of the Southern 
                         Ocean. There are several studies in the literature that suggest 
                         some kind of teleconnection between the Sea Ice (SI) fields and 
                         the global climate. Based on this hypothesis, this work intends to 
                         analyze if the ADP pattern is manifested in the field of seasonal 
                         anomalies of Sea Ice Concentration (SIC) and atmospheric variables 
                         of two current reanalysis databases during extreme events of the 
                         El Niņo Southern Oscillation (ENSO). The second stage aims to 
                         evaluate the leading seasonal modes variability of the SIC field 
                         and the adjacent atmospheric fields, i.e., Sea Level Pressure 
                         (SLP) and Surface Air Temperature (SAT). The study comprises the 
                         period between 1979 and 2014.The link between the atmospheric 
                         variables and SI during the ENOS event result in a persistence of 
                         SI anomalies by configuring a confined ADP pattern between the 
                         Atlantic and Pacific sectors of the Southern Ocean. In all 
                         compositions it has been found that the ADP standard is much more 
                         defined in SIC compounds in winter and spring. The influence of 
                         ADP on SI variability, as well as on the atmosphere, was not 
                         detected in the austral summer. Another point of discussion is the 
                         nature of the displacement of the centers of positive and negative 
                         anomalies of the SLP, during El Niņo events. It was found that the 
                         location of the centers of anomalies did not coincide with the 
                         Atlantic and Pacific regions of the Southern Ocean; a center of 
                         positive anomaly centered on the Drake Pass is an example. Through 
                         the Geopotential Height (HGT) anomaly fields it was verified that 
                         the cyclonic and anticyclonic patterns that are confined between 
                         the Southern Ocean sectors remained the same vertical structure 
                         throughout their depth, indicating that the atmospheric signal is 
                         basically barotropic. The analysis of the Empirical Orthogonal 
                         Functions (EOF) shows that the first modes of variability of SIC, 
                         summer (DJF) and autumn (MAM), in the Southern Ocean, present a 
                         yearon- year frequency. However, the leading modes of winter sea 
                         ice (JJA) and spring (SON) show the ADP pattern and are associated 
                         with the influence of ENSO. The first modes of EOF associated to 
                         the SLP, in all the stations reveal characteristics of the 
                         Antarctic Oscillation (AAO). In general, this work fulfilled the 
                         objective of verifying the responses of the ENSO influence to the 
                         atmospheric field anomalies and associated impacts on sea ice, in 
                         inter-annual scale.",
            committee = "Coelho, Caio Augusto dos Santos (presidente) and Pezzi, Luciano 
                         Ponzi (orientador) and Gherardi, Douglas Francisco Marcolino and 
                         Justino, Fl{\'a}vio Barbosa",
         englishtitle = "Joint influence of El Niņo-southern oscillation and Antarctic 
                         dipole on the Bellingshausen-Amundsen seas sea ice and the Weddell 
                         sea",
             language = "pt",
                pages = "135",
                  ibi = "8JMKD3MGP3W34P/3PGUL5B",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3PGUL5B",
           targetfile = "publicacao.pdf",
        urlaccessdate = "03 dez. 2020"
}


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