Probability of rainfall for the city of Cruzeiro do Sul, Acre, Brazil

Abstract

Due to randomness in the occurrence of hydrological phenomena, the estimation of probable rain precipitation in a given region is important in assisting decision-making. This work aimed to adjust the probabilistic model of the Gamma distribution to the monthly and annual rainfall totals recorded in the city of Cruzeiro do Sul, Acre, for the period between 1970 and 2019, in addition to estimating the expected values at different probability levels. Using the maximum likelihood method, the distribution parameters were estimated, with adherence ratified by the Kolmogorov-Smirnov test. The results showed that the Gamma distribution was adequate to adjust the data; the region has two well-defined periods in its rainfall pattern; the mean precipitation values recorded in the locality are between 25% and 40% of probability. Finally, probable rainfall values were presented at different probability levels for the city of Cruzeiro do Sul.

Variabilidade da precipitação e relação com a produtividade de mandioca (Manihot Esculenta) na Cidade de Cruzeiro do Sul, Acre

“…A partir do ano de 1995, verificou-se que os valores registrados de precipitação pluviométrica se distanciam do valor médio (para mais ou para menos). Tal verificação explicita a variabilidade no regime de chuvas presente na região, conforme relatado por Silva et al (2021). Apesar de alguns anos em que o índice de precipitação pluviométrica ocorreu aumento de um ano para o outro, a produção de mandioca não seguiu a mesma tendência no mesmo período.…”

“…De acordo com Silva et al (2021), a classificação climática de Nimer (1979), destaca a influência da temperatura e da umidade na diversidade climática da região. Dessa forma, a região é destacada com o tipo climático equatorial quente, com média diária de temperatura superior a 18 ºC em todos os meses, e com distribuição de umidade do tipo super úmido a subseco (Figura 1).…”

“…Dessa forma, é importante analisar o papel das variáveis pluviais e sua relação com a produção agrícola, destacandose, no presente estudo, a cultura da mandioca (Manihot esculenta). De acordo com Silva et al (2021), o regime pluviométrico impacta fortemente na produtividade agrícola e, consequentemente, nos aspectos sociais, econômicos e políticos inerentes ao processo de produção.…”

Temporal Trend and Estimation of the Hydrological Risk of Maximum Rainfall and Flow Extremes in the City of Rio Branco, Acre, Brazil

“…The definition of a distributive model capable of describing the probabilistic characteristics of a hydrometeorological phenomenon requires the estimation of its parameters, which, in this work, used the maximum likelihood method (Du et al, 2015). After adjusting the distribution, the adherence of the data should be verified, considering the Kolmogorov-Smirnov and chi-square (χ 2 ) tests (Silvino et al, 2007;Silva et al, 2021).…”

Heavy rainfall events in the state of Acre, western Amazonia

“…Therefore, methods aimed at estimating values associated with the frequency and magnitude of such events are a priority for contemporary science, notably with regard to the temporal 2018) emphasized that rainfall is a natural event that triggers other processes (extreme oods, for example) and that the modern concept of risk management consists of two parts: the probability of the occurrence of the harmful event and analyses of losses related to that event. Dos Santos Silva et al (2021) emphasized that rain is generally the beginning of a sequence of process that has several important implications for industry, agriculture, energy transformation, etc., and can substantially improve the social and economic development of nations. Tavares and Santos (2022) reinforced this line of reasoning and elucidated that knowledge about the behaviour of rainfall is important for various economic and social sectors and is an important planning tool for urban and rural projects and activities.…”