The spacialization of climatic variables, especially the precipitation, needs constant studies. The precipitation is one of the more important meteorological variables for the climatic studies of the several areas of Brazil, mainly, due to the consequences, in the economical and social sections, occurred in excess or shortage periods. In this sense, the present research looked for to perceive the rainfall of the Territory of Identity called Portal do sertão, in Bahia, because from 17 municipal districts that compose this area, only ten of them have climatological data. The methodological base of the work concentrated on the use and evaluation of some of the principal interpolation methods (inverse considered of the distance; kriging; spline and triangulation with linear interpolation). The interpolation is constituted in a method of esteeming a parameter for which available information doesn't exist, being considered that the neighbor points in the space tend to have more similar values than distant points. The most appropriate result was obtained by the kriging, followed for the minimum and inverse curvature considered of the distance. Being considered that the interpolation just supplies an estimate of a value based on other known values is believed that the distribution of the stations and the low density of data were responsible for the bad quality of the results obtained by most of the analyzed methods. The reached results confirm the degree of relevance of this study, especially in the ambit of the measurement of rainfall data.Pages: 4295-430
