Extreme hydroclimatic events in the Spring of Para?ba do Sul Watershed, S?o Paulo

Autor: Coelho, Andr? Luis de Souza
Přispěvatelé: Lyra, Gustavo Bastos, Herms, Friedrich Wilhelm, Souza, Lucio Silva de, Abreu, Marcel Carvalho
Jazyk: portugalština
Rok vydání: 2019
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações da UFRRJ
Universidade Federal Rural do Rio de Janeiro (UFRRJ)
instacron:UFRRJ
Popis: Submitted by Leticia Schettini (leticia@ufrrj.br) on 2021-10-27T13:26:02Z No. of bitstreams: 1 2019 - Andr? Luis de Souza Coelho.pdf: 3419856 bytes, checksum: 7a7db3ab15f49e80c7395408cd2f48dd (MD5) Made available in DSpace on 2021-10-27T13:26:02Z (GMT). No. of bitstreams: 1 2019 - Andr? Luis de Souza Coelho.pdf: 3419856 bytes, checksum: 7a7db3ab15f49e80c7395408cd2f48dd (MD5) Previous issue date: 2019-08-20 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior 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. Os impactos sobre os recursos h?dricos devem ser reduzidos para se manter o modo de vida atual e futuro. Avaliou-se influ?ncia dos extremos de precipita??o e vaz?o nas cabeceiras da Bacia do Rio Para?ba do Sul e sua rela??o com os modos de variabilidade clim?tica. Os extremos foram caracterizados por meio de ?ndices padronizados, buscando analisar a din?mica dos mesmos e sua rela??o com os modos de variabilidade clim?tica. Na regi?o localizam-se tr?s reservat?rios (Paraibuna, Santa Branca e Jaguari), principalmente, utilizados para gera??o de energia el?trica, abastecimento e controle de inunda??es. Foram utilizadas s?ries de precipita??o de sete esta??es meteorol?gicas e tr?s pontos de medi??o de vaz?o natural entre janeiro/1972 e dezembro/2016. As s?ries de precipita??o passaram por tratamento de qualidade e preenchimento de falhas. Foi utilizado o Standardized Precipitation Index (SPI) para anomalias de precipita??o e o Streamflow Drought Index (SDI) para anomalia de vaz?o. Os ?ndices foram calculados nas escalas de 3, 6 e 12 meses para avaliar os anos hidrol?gicos, semestres e trimestres secos e ?midos. As s?ries passaram por testes estat?sticos que permitiram a an?lise de tend?ncia. Foi realizada a correla??o entre SPI e SDI para as tr?s escalas de tempo. Os ?ndices clim?ticos dos modos de variabilidade clim?tica: Oscila??o Decadal do Pac?fico (ODP), El Ni?o Oscila??o Sul (ENOS) e Gradiente Inter-hemisf?rico de TSM do Atl?ntico (GITA) foram analisados. As s?ries temporais foram submetidas a an?lise harm?nica e espectral. As an?lises de SPI caracterizaram 79 anomalias, sendo 39 anos secos e 40 ?midos, enquanto o SDI apresentou 37 anomalias, sendo 15 secos e 22 ?midos. N?o foram verificadas tend?ncias estat?sticas significativas nas s?ries. As an?lises de correla??o demostraram correla??o com r > 0,5 para todas as avali??es, com exce??o de quatro esta??es na escala de tr?s meses para a esta??o seca e uma esta??o na escala de seis meses para semestre ?mido. A maior frequ?ncia de ocorr?ncia de extremos nas esta??es ocorreu em cinco anos secos e seis anos ?midos. A s?rie pode ser dividida entre dois per?odos caracter?sticos, o primeiro de 1972 a 1993 e, o segundo de 1994 a 2016. O primeiro per?odo apresentou anos com predomin?ncia de anomalia positiva no semestre seco e na esta??o seca e no segundo observou-se uma invers?o, com anomalia negativas no semestre ?mido e na esta??o chuvosa. O primeiro harm?nico apresentou per?odo entre 11 e 22 anos para escala decadal e pode estar relacionado com ODP ou GITA. O segundo e terceiro harm?nicos entre 2 e 7 anos para escala interanual pode estar relacionada com o fen?meno ENOS. Foi poss?vel observar a ocorr?ncia de extremos clim?ticos e caracterizar sua frequ?ncia. Foram observados ciclos entre tr?s e seis anos para a ocorr?ncia de extremos clim?ticos. A frequ?ncia de extremos de precipita??o e vaz?o apresentaram rela??o, entretanto a intensidade desses fen?menos n?o pode ser observada com a mesma clareza. O estudo realizado contribui, assim, para transi??o dos sistemas tradicionais de gest?o para sistemas alinhados ao modelo de desenvolvimento sustent?vel.
Databáze: OpenAIRE
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