Close
Metadata

@MastersThesis{Lira:2019:CaEsSe,
               author = "Lira, Tamires Alybia Gomes de",
                title = "Caracteriza{\c{c}}{\~a}o espa{\c{c}}o-temporal das secas sobre 
                         o Brasil nas {\'u}ltimas d{\'e}cadas (1981-2016)",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2019",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2019-08-14",
             keywords = "secas, {\'{\i}}ndice de sa{\'u}de da vegeta{\c{c}}{\~a}o 
                         (ISV), diagn{\'o}stico clim{\'a}tico, drought, vegetation health 
                         index (VHI), climatic diagnostic.",
             abstract = "Fen{\^o}menos de seca frequentemente s{\~a}o alvos de estudos 
                         meteorol{\'o}gicos devido {\`a} severidade de seus impactos 
                         tanto ao meio ambiente quanto {\`a} sociedade em geral. 
                         Ultimamente, alguns desses estudos, realizados para as 
                         regi{\~o}es Nordeste, Sudeste e regi{\~a}o Norte Brasil, com 
                         objetivo de investigar as secas atrav{\'e}s de perspectivas tais 
                         como a frequ{\^e}ncia de ocorr{\^e}ncia, dura{\c{c}}{\~a}o e 
                         intensidade, aparentemente demonstram que as {\'a}reas atingidas 
                         pelas secas t{\^e}m aumentado a cada evento. Sendo assim, o 
                         presente trabalho tem como objetivo caracterizar as secas em seu 
                         aspecto espacial e temporal para todo territ{\'o}rio brasileiro 
                         nas {\'u}ltimas d{\'e}cadas (1981 - 2016). Para isso, foram 
                         utilizados dados de precipita{\c{c}}{\~a}o, 
                         precipita{\c{c}}{\~a}o-evapora{\c{c}}{\~a}o e o 
                         {\'{\I}}ndice de Sa{\'u}de da Vegeta{\c{c}}{\~a}o (ISV) 
                         estimado a partir de dados de sat{\'e}lite. Al{\'e}m de 
                         diagnosticar esse aspecto do fen{\^o}meno, tamb{\'e}m 
                         prop{\~o}e-se a investigar a expans{\~a}o espacial das secas ao 
                         longos dos anos sob o ponto de vista de poss{\'{\i}}veis 
                         mudan{\c{c}}as nos padr{\~o}es de circula{\c{c}}{\~a}o 
                         atmosf{\'e}rica, varia{\c{c}}{\~a}o na distribui{\c{c}}{\~a}o 
                         de precipita{\c{c}}{\~a}o ou ainda altera{\c{c}}{\~o}es no 
                         comportamento da TSM (Temperatura da Superf{\'{\i}}cie do Mar). 
                         Como material de estudos das conex{\~o}es dos eventos de secas e 
                         as demais vari{\'a}veis meteorol{\'o}gicas foram utilizados 
                         dados de circula{\c{c}}{\~a}o atmosf{\'e}rica do CFSR (Climate 
                         Forecast System Reanalysis), de precipita{\c{c}}{\~a}o do MSWEP 
                         (Multi-Source Weighted-Ensemble Precipitation), 
                         precipita{\c{c}}{\~a}o-evapotranspira{\c{c}}{\~a}o e 
                         velocidade vertical (omega) da rean{\'a}lise ERA-Interin e de TSM 
                         da s{\'e}rie de Reynolds. Os resultados mostraram que os 
                         {\'{\i}}ndices de vegeta{\c{c}}{\~a}o e de umidade indicam 
                         aumento das {\'a}reas de seca no Brasil para as {\'u}ltimas 
                         d{\'e}cadas, principalmente para o per{\'{\i}}odo decenal de 
                         2008 - 2016. O trimestre DJF mostrou tend{\^e}ncias lineares mais 
                         marcadas para este mesmo per{\'{\i}}odo, indicando um aumento 
                         das {\'a}reas atingidas por condi{\c{c}}{\~o}es de seca em todo 
                         o pa{\'{\i}}s durante o ver{\~a}o. As an{\'a}lises das 
                         anomalias de TSM e circula{\c{c}}{\~a}o indicaram 
                         condi{\c{c}}{\~o}es de La Niņa ou El Niņo atuando em sete dos 
                         noves anos da s{\'e}rie decenal. As an{\'a}lises das 
                         circula{\c{c}}{\~o}es locais (para a Am{\'e}rica do Sul) e dos 
                         movimentos verticais indicaram que al{\'e}m das anomalias de 
                         circula{\c{c}}{\~a}o provocada por eventos ENOS na 
                         circula{\c{c}}{\~a}o geral da atmosfera (ramo descendente da 
                         c{\'e}lula de Walker no Brasil) a atua{\c{c}}{\~a}o de 
                         anomalias de circula{\c{c}}{\~a}o anticicl{\^o}nica, 
                         principalmente nos {\'u}ltimos anos da d{\'e}cada, 
                         contribu{\'{\i}}ram para o aumento das {\'a}reas de seca no 
                         pa{\'{\i}}s. ABSTRACT: Drought events have caused severe impacts 
                         to the environment and society being therefore subject of several 
                         studies. Recently, some researches were performed aiming to 
                         investigate droughts throughout their frequency of occurrence, 
                         duration and intensity for the Northeast, Southeast and the 
                         Northern regions of Brazil. Results have shown that affected areas 
                         increased each year. However, how large was the increase over the 
                         whole country has not been explored. Thus, this research aims to 
                         characterize droughts events in their spatial and temporal aspects 
                         over all Brazilian territory during the last decades (1981 - 
                         2016). In addition, possible changes in the atmospheric 
                         circulation patterns, modifications in the distribution of the 
                         precipitation and changes in the Sea Surface Temperature (SST) 
                         patterns were also investigated. For such purposes various 
                         datasets were used, including precipitation data from the 
                         Multi-Source Weighted-Ensemble Precipitation (MSWEP), Climate 
                         Forecast System Reanalysis (CFSR) for the atmospheric circulation 
                         data, precipitationevaporation and vertical velocity (omega) data 
                         from the ERA-Interim reanalysis, SST data from Reynolds series and 
                         the Vegetation Health Index (VHI) estimated from satellite data. 
                         Analyses for the vegetation, precipitation and 
                         precipitationevaporation data were based on statistic aspects such 
                         as angular coefficients and p value of their quarterly and annual 
                         temporal series, which were created using a threshold to specify, 
                         in percentage, drought conditions over the country. Temporal 
                         series that pointed out an increase in the drought areas were 
                         chosen to create composites for the other variables, such as 
                         circulation, SST and vertical velocity. An expressive increase of 
                         the areas affected by droughts conditions was showed in the anual 
                         VHI series for the entire period of study, as well as for the last 
                         decade in the decenal VHI series. These aspects were reproduced in 
                         the quarterly series for the austral summer (DJF), in all indexes 
                         analyzed, specially in the last decenal period (2007/08 - 
                         2015/16). The composites for the SST and atmospheric circulation 
                         anomalies indicated that ENSO (El Niņo-Southern Oscillation) 
                         events were associated with anomalous anticyclonic circulation 
                         patterns, especially in the last three years of the decenal serie 
                         (2014, 2015 and 2016). Its combined occurrence played an important 
                         role in the maintenance and expansion of the areas affected by 
                         drought conditions during the summer of the last decenal period, 
                         contributing to the increasing of the total area.",
            committee = "Arav{\'e}quia, Jos{\'e} Antonio (presidente) and Coelho, Caio 
                         Augusto dos Santos (orientador) and Santos, Renata Libonati dos",
         englishtitle = "Spatial and temporal characterization of droughts over Brazil in 
                         last decades (1981-2016)",
             language = "pt",
                pages = "132",
                  ibi = "8JMKD3MGP3W34R/3TRGGPL",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34R/3TRGGPL",
           targetfile = "publicacao.pdf",
        urlaccessdate = "2019, Nov. 19"
}


Close