Precipitação pluviométrica na bacia hidrográfica do Rio Vacacaí, RS

Abstract

The aim of this research is to present, through de application of statistic models and the confection of digital maps, a temporal and special analysis of rainfall in the hydrographic basin of Vacacaí river, in the State of Rio Grande do Sul. The research is divided in three articles: a) homogeneity of rainfall data recorded both in the area and the surroundings of Vacacaí River; b) average and variability analysis of rainfall in the area and surroundings of the hydrographic basin of Vacacaí river and c) spatialization of rainfall in the hydrographic basin of Vacacaí river, RS. The first article addresses the importance of the study of the homogeneity of meteorological data and through the application of two different statistic techniques (double mass and test of iterations), obtaining as a result the possibility of data usage from all the tested rain stations. The second article brings about a more broad vision of the monthly and annual rainfall measures and their variability in the area of study, graphically representing and describing the rainfall relation with the decadal oscillation from the Pacific Ocean, being possible to observe the existence of temporal variation of rainfall. The third article approaches the cartographic representation of both monthly and annual total rainfall in the hydrographic basin of Vacacaí river, being possible to identify the influence of the terrain altimetry in the space distribution of the rain.