Eventos hidroclim?ticos extremos nas cabeceiras da Bacia do Rio Para?ba do Sul, S?o Paulo

• Ano de defesa: 2019
• Autor(a) principal: Coelho, Andr? Luis de Souza
• Orientador(a): Lyra, Gustavo Bastos
• Banca de defesa: Souza, Lucio Silva de , Abreu, Marcel Carvalho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Rio de Janeiro
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Pr?ticas em Desenvolvimento Sustent?vel
• Departamento: Instituto de Florestas
• País: Brasil
• Palavras-chave em Português: Recursos H?dricos; Extremos Hidrometeorol?gicos; Variabilidade Clim?tica
• Palavras-chave em Inglês: Water Resources; Hydrometeorological Extremes; Climate Variability.
• Área do conhecimento CNPq: Recursos Florestais e Engenharia Florestal
• Link de acesso: https://tede.ufrrj.br/jspui/handle/jspui/5175

The impacts on water resources must be reduced to maintain current and future lifestyle. The influence of precipitation and streamflow extremes in the spring of the Para?ba do Sul Watershed and their relationship with the climate variability modes were evaluated. The extremes were characterized by standardized indices to analyze the dynamics and relationship with the climate variability modes. There are three reservoirs (Paraibuna, Santa Branca and Jaguari) in this region, mainly used for power generation, fresh water supply and flood control. The precipitation series were used from seven weather stations and three natural flow measurement points for the period between January 1972 and December 2016. The precipitation series underwent quality treatment and gap filling. Standardized Precipitation Index (SPI) was used for precipitation anomalies and Streamflow Drought Index (SDI) for flow anomalies. The indices were calculated on the scales of 3, 6 and 12 months to evaluate the hydrological years, dry and wet semesters and seasons. A trend analysis was performed. Correlation between SPI and SDI was performed for the three timescales. The climate indices were analyzed of the following climate variability modes: Pacific Decadal Oscillation (PDO), El Ni?o Southern Oscillation (ENSO) and Atlantic Interhemispheric SST Gradient (AISG). The time series were subjected to harmonic and spectral analysis. SPI analyzes characterized 79 anomalies, of which 39 dry and 40 wet years, while SDI identified 37 anomalies, of which 15 dry and 22 wet. No significant statistical trends were found in the series. There was correlation with r> 0.5 for all evaluations except for four seasons on the three-month dry season scale and one season on the six-month wet semester scale. The most frequent occurrence of extremes in the seasons occurred in five dry years and six wet years. The series can be divided into two characteristic periods, the first from 1972 to 1993 and the second from 1994 to 2016. The first period showed years with predominance of positive anomalies in the dry semester and the dry seasons, and in the second period there was an inversion, with negative anomalies in the wet semester and the rainy seasons. The first harmonic presented a period between 11 and 22 years for decadal scale and may be related to ODP or GITA. The second and third harmonics between 2 and 7 years for interannual scale may be related to the ENSO phenomenon. It was possible to observe the occurrence of climatic extremes and characterize their frequency. Cycles between three and six years were observed for the occurrence of climatic extremes. The frequency of precipitation and streamflow extremes were related, however the intensity of these phenomena cannot be observed with the same clarity. The study thus contributes to the transition from traditional management systems to systems aligned with the sustainable development model.