Análise de frequência: cotas e vazões do rio Solimões, máximas e mínimas, na Estação 14100000 - Manacapuru

Abstract

The Amazon stands out not only for its vast and diverse biome, but also for its complex hydrography. The Amazon region is characterized by its intense and seasonal rainfall, with frequent rains and well-defined flood and drought regimes. The main river is the Amazon. The upper stretch of the Amazon River is called the Solimões River. Frequency analysis is a fundamental tool within statistical hydrology, which aims to study the probability of occurrence of extreme hydrological events, such as maximum and minimum flows. In the case of the Solimões River, frequency analysis is the basis for managing extreme events, such as estimating the hydrological risk of floods and droughts and planning infrastructure and measures toadapt to climate change. The aim of this Final Paper is to study and analyse the frequencies of maximum and minimum levels, maximum flows and minimum flows of the Solimões River at the fluviometric station 14100000 - Manacapuru, organizing the available hydrological data, applying statistical methods, and finally obtaining the analyses. The specific objectives of the study include acquiring the fluviometric data, preparing the historical series of maximum and minimum flows, testing the fit of the series to the Probability Distribution Functions and implementing the frequency analysis for the maximum and minimum probable flows. The results of the survey offer water resources professionals a valuable tool for determining the return period and the risk associated with the levels measured on site. For example, in the dry season of 2023, the Solimões River's level was recorded at 3.61 meters, surpassing the historic low of 2010, which was 3.92 meters. Based on the results of the frequency analysis, it is estimated that the return time for this level is approximately 268 years. Due to the constant evolution of the historical data series, it is essential to update the frequency analysis regularly, which indicates trends in the hydrological regime of the rivers. In conclusion, the study fully achieved its proposed objective, providing a solid base of information and tools for managing water resources in the region, considering the complex hydrography and importance of the Solimões River.