Avaliação de tendências em séries de precipitação diária máxima anual na faixa central do estado de Minas Gerais

• Ano de defesa: 2013
• Autor(a) principal: Marise Aparecida Queiroz
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Minas Gerais; UFMG
• Palavras-chave em Português: Meio Ambiente e Recursos Hídricos; Saneamento; Recursos hídricos Desenvolvimento; Precipitação (Meteorologia); Engenharia sanitária
• Link de acesso: http://hdl.handle.net/1843/BUBD-9HMJ6Y

The purpose of this study is to evaluate the presence of trend in 36 series of daily precipitation selected throughout the central area of the State of Minas Gerais. In order to do so, the presence of trend in time series data was analyzed using Rclimdex software; the presence of trend in the maximum daily precipitation series per hydrological year (Pdmah) was evaluated and a possible change in Pdmah series frequency was verified, as well as the possible influence of El Niño South Oscillation and the decadal Oscillation of the Pacific (PDO) on the Pdmah. The analysis of the presence of trend in the time series of precipitation index indicated that the number of consecutive dry days, the number of days with precipitation higher than or equal to 10 mm and the total precipitation per hydrological year does not present trend in the central area of Minas Gerais State. The index of extremely rainy days (R99p), number of days with precipitation over 30 mm (R30mm), quantity of maximum precipitation in 5 days (Rx5d) and the index of daily intensity (Sdii) that presented significant trend, predominated positive, being most of the stations that obtained such results are located in latitudes higher than 19° South. The Mann- Kendall, Spearmans Rho trend tests and the Linear Regression indicate that 8 stations present significant positive trend. The results of frequency analysis for the complete period of data, the first and the last 30 years of data of the time series indicated a dichotomous behavior for the stations located in latitudes higher than 19° south. The analysis conducted in this study, does not allow for unmistakable conclusions of the identification of trends or spatial variation patterns of maximum daily precipitation per hydrological year in the central area of Minas Gerais. But, only hints of the ocurrence of positive trends at latitudes over 19º South. The analysis carried out in this study does not allow to state that these abnormalities are directly associated to the extreme phases of El Niño South Oscillation. However, results indicate a possible influence of decadal Oscillation of the Pacific on the frequency of maximum daily precipitation per hydrological year. During the periods of heat PDO phase there seems to be a trend of higher frequency of more elevated values of Pdmah than during the cold phase.