Frequência de ocorrência de precipitação pluviométrica em Montes Claros-MG

Abstract

Most of the irrigation projects implemented in regions with supplemental to rainfall have been prepared in terms of total irrigation; this practice makes the systems are oversized. The literature recommends that in such cases, be adopted at the time of design, the criterion of likely precipitation, ie, that amount of precipitation that occurs at a certain level of probability; it is necessary, then, to define for each region, the values of rainfall likely to occur at different levels of probability. Knowledge of the frequency of rainfall is of extreme interest for the design of spillways for dams, canals, storm sewers, culverts and dams for water supply and for agricultural planning and design of supplementary irrigation system. This paper aims to present an analysis of frequency of occurrence of rainfall in the city of Montes Claros- MG. We used a database of 20 years of daily rainfall, from INMET, from which we calculated the frequency of occurrence of rainfall. Through this research can be observed that the average annual rainfall was 1017.11 mm with standard deviation of 258.32 mm and showed a total of 1632 rainy days with an average of 82.10 days of rain per year. The highest rainfall during this period was 145 mm, and the range of 140.1-145 mm its frequency of occurrence is in 0.03%, against starting the day that there was no rain for the greater 77.39 %, with probability and the range of 0.1-5.0 mm was the highest frequency of precipitation 22.61%.