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@PhDThesis{Quispe:2022:EsNu,
               author = "Quispe, David Pareja",
                title = "Import{\^a}ncia de fatores f{\'{\i}}sicos na ocorr{\^e}ncia de 
                         dois eventos h{\'{\i}}dricos extremos na regi{\~a}o 
                         Amaz{\^o}nica: Um estudo num{\'e}rico",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2022",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2021-11-29",
             keywords = "eventos extremos, seca, chuvoso, separa{\c{c}}{\~a}o de fatores, 
                         RegCM4, extreme events, drought, flood, factor separation.",
             abstract = "O modelo RegCM4 foi usado para investigar a influ{\^e}ncia de 
                         tr{\^e}s fatores f{\'{\i}}sicos na ocorr{\^e}ncia de dois 
                         eventos extremos (seco de 2004-05 e chuvoso de 2008-09) na bacia 
                         Amaz{\^o}nica (BA). Para examinar o papel da temperatura da 
                         superf{\'{\i}}cie do mar (TSM), gases do efeito estufa (GEE), 
                         umidade do solo (SM) e suas sinergias sobre a 
                         precipita{\c{c}}{\~a}o, o m{\'e}todo de separa{\c{c}}{\~a}o 
                         de fatores foi usado. Para isso, foi feita uma 
                         simula{\c{c}}{\~a}o continua de 34 anos com o RegCM4 sobre o 
                         dom{\'{\i}}nio CORDEX da Am{\'e}rica do Sul (AS). O modelo foi 
                         for{\c{c}}ado com a rean{\'a}lise ERA-Interim (EIN15). A 
                         princ{\'{\i}}pio, avaliamos o desempenho do RegCM4, sobretudo as 
                         vari{\'a}veis associadas a circula{\c{c}}{\~a}o 
                         atmosf{\'e}rica, ao balan{\c{c}}o de radia{\c{c}}{\~a}o {\`a} 
                         superf{\'{\i}}cie e ao ciclo hidrol{\'o}gico. Apesar de algumas 
                         defici{\^e}ncias, o modelo reproduziu bem o padr{\~a}o geral das 
                         vari{\'a}veis analisadas em compara{\c{c}}{\~a}o com as 
                         observa{\c{c}}{\~o}es (EIN15, CLARA2 e CRU/PERSIANN). Na segunda 
                         parte, o per{\'{\i}}odo de dezembro-fevereiro foi selecionado 
                         para avaliar os dois eventos extremos. A avalia{\c{c}}{\~a}o foi 
                         feita a partir de uma rodada de longo prazo, chamado de 
                         experimento controle. Os resultados mostraram que o RegCM4 pode 
                         reproduzir a distribui{\c{c}}{\~a}o espacial e temporal das 
                         anomalias negativas da precipita{\c{c}}{\~a}o no 
                         per{\'{\i}}odo de seca entre 2004-05 e as anomalias positivas no 
                         per{\'{\i}}odo chuvoso de 2008-09 sobre a BA, o que indica que o 
                         RegCM4 {\'e} {\'u}til para simular eventos hidro-clim{\'a}ticos 
                         extremos. Finalmente, os experimentos de sensibilidade 
                         considerando a import{\^a}ncia relativa dos tr{\^e}s fatores 
                         diretos e seus efeitos combinados foram realizados. Para cada 
                         experimento, a m{\'e}dia do conjunto de cinco membros foi usado 
                         na an{\'a}lise. Os resultados para o evento extremo seco, no 
                         ver{\~a}o austral de 2004-05, mostraram que os fatores diretos da 
                         TSM e GEE e o sinergismo entre os tr{\^e}s fatores desempenham um 
                         papel muito importante na ocorr{\^e}ncia da seca na BA. O fator 
                         TSM {\'e} o mais importante contribuindo com aumentos de 
                         precipita{\c{c}}{\~a}o superiores a 50%, enquanto o fator GEE 
                         contribui com aumentos pr{\'o}ximos a 30%. Isto mostra que o 
                         fator TSM foi o principal fator que favoreceu a ocorr{\^e}ncia do 
                         epis{\'o}dio seco 2004-05 na BA. A sinergia dos tr{\^e}s fatores 
                         tamb{\'e}m contribu{\'{\i}}ram com aumentos de 
                         precipita{\c{c}}{\~a}o pr{\'o}ximo a 50% nas regi{\~o}es do 
                         centro e sul da BA. Al{\'e}m disso, sugere-se que as 
                         condi{\c{c}}{\~o}es mais {\'u}midas do solo podem reduzir a 
                         intensidade dos eventos secos. Os resultados para o evento extremo 
                         chuvoso, no ver{\~a}o austral de 2008-09, mostraram que o efeito 
                         direto do fator GEE foi o mais importante, apresentando grandes 
                         extens{\~o}es com redu{\c{c}}{\~o}es de 
                         precipita{\c{c}}{\~a}o de at{\'e} -30% na BA. O fator TSM 
                         tamb{\'e}m contribui com redu{\c{c}}{\~o}es de 
                         precipita{\c{c}}{\~a}o superiores a 20%, por{\'e}m, apresentam 
                         menor extens{\~a}o aos observados no experimento do fator GEE. O 
                         efeito combinado dos tr{\^e}s fatores apresentaram 
                         redu{\c{c}}{\~o}es de precipita{\c{c}}{\~a}o de at{\'e} -30%, 
                         com extens{\~a}o semelhante aos observados no experimento do 
                         fator GEE. Isto indica que no caso chuvoso, a sinergia dos 
                         tr{\^e}s fatores (TSM, GEE e SM) {\'e} importante junto ao fator 
                         GEE. Em todos os experimentos de sensibilidade, a T2m apresentou 
                         efeitos de sinal positivo nas regi{\~o}es onde 
                         redu{\c{c}}{\~o}es de precipita{\c{c}}{\~a}o prevaleceram, e o 
                         sinal contr{\'a}rio foi observado em regi{\~o}es com aumentos de 
                         precipita{\c{c}}{\~a}o. Uma vez que as intera{\c{c}}{\~o}es 
                         n{\~a}o lineares n{\~a}o podem ser bem avaliadas, mais estudos 
                         s{\~a}o necess{\'a}rios para entender melhor os mecanismos 
                         dominantes envolvidos. ABSTRACT: The RegCM4 model was used to 
                         investigate the influence of three physical factors on the 
                         occurrence of two extreme events (2004-05 drought and 2008-09 
                         flood) in the Amazon basin (AB). To examine the role of sea 
                         surface temperature (SST), greenhouse gases (GHG), soil moisture 
                         (SM) and their synergies on precipitation the factor separation 
                         method was used. For this purpose, a 34-years simulation was 
                         performed with RegCM4 on the CORDEX domain of South America (SA). 
                         The model was forced with ERA-Interim reanalysis (EIN15). At 
                         first, we assess the RegCM4 performance, especially the variables 
                         associated with atmospheric circulation, the surface radiation 
                         budget and the hydrological cycle. Although some deficiencies, the 
                         model reproduced well the general pattern of the variables 
                         analyzed in comparison with the observations (EIN15, CLARA2 and 
                         CRU/PERSIANN). In the second part, the period December-February 
                         was selected to evaluate the two extreme events. The evaluation 
                         was made from a long-term run, called a control experiment. The 
                         results showed that RegCM4 can reproduce the spatial distribution 
                         and temporal evolution of negative precipitation anomalies in the 
                         2004-05 drought event and positive anomalies in the 2008-09 flood 
                         event over AB, which indicates that RegCM4 is useful for 
                         simulating hydro-climatic extreme events. Finally, sensitivity 
                         experiments considering the relative importance of the three 
                         direct factors and their combined effects were performed. For each 
                         experiment, the five-member ensemble-averaged is used in the 
                         analysis. The results, for the extreme drought event in the 
                         austral summer of 2004-05, showed that the direct factors of SST 
                         and GHG and the synergism between the three factors play a very 
                         important role in the occurrence of drought in AB. The SST factor 
                         is the most important contributing with increases in precipitation 
                         above 50%, while the GHG factor contributes with increases around 
                         30%. This shows that the SST factor was the main factor that 
                         favored the occurrence of the 2004-05 extreme drought episode in 
                         AB. The synergy of the three factors also contributed to 
                         precipitation increases close to 50% in the central and southern 
                         regions of AB. Moreover, it is suggested that wetter soil 
                         conditions can reduce the intensity of drought events. The results 
                         for the extreme flood event in the austral summer 2008-09, showed 
                         that the direct effect of the GHG factor was the most important, 
                         presenting large extensions with precipitation reductions in AB 
                         with values of up to -30%. The SST factor also contributes with 
                         precipitation reductions greater than 20%, however, they are less 
                         extensive than those observed in the GHG factor experiment. The 
                         combined effect of the three factors showed precipitation 
                         reductions of up to -30%, with a similar extent to those observed 
                         in the GHG factor experiment. This indicates that in the extreme 
                         flood case, the synergy of the three factors (SST, GHG and SM) is 
                         important together with the GHG factor. In all sensitivity 
                         experiments, T2m showed positive sign effects in regions where 
                         precipitation reductions prevailed, and the opposite sign was 
                         observed in regions with precipitation increases. Since nonlinear 
                         interactions are not yet well knowledge, further studies are 
                         needed to better understand the dominant mechanisms involved.",
            committee = "Gon{\c{c}}alves, Luis Gustavo Gon{\c{c}}alves de (presidente) 
                         and Fernandez, Julio Pablo Reyes (orientador) and Gan, Manoel 
                         Alonso and Rocha, Rosmeri Porfirio da and Reboita, Michelle 
                         Sim{\~o}es",
         englishtitle = "Importance of physical factors in the occurrence of two extreme 
                         hydrological events in the Amazon region: A numerical study",
             language = "pt",
                pages = "159",
                  ibi = "8JMKD3MGP3W34T/45R3SM8",
                  url = "http://urlib.net/ibi/8JMKD3MGP3W34T/45R3SM8",
           targetfile = "publicacao.pdf",
        urlaccessdate = "23 maio 2024"
}


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