Flow regionalization using precipitation data from different bases as a predictive variable.

In studies of flow regionalization, the uncertainties associated with the precariousness or non-existence of flow and precipitation data are problems faced by researchers and managers of water resources, especially in emerging countries such as Brazil. Given this, the usage of precipitation databases obtained by satellites has become more prevalent, allowing accurate precipitation estimates in regions where punctual data obtained from rain gauges are precarious. Therefore, the objective of this study was to compare different precipitation databases, used as predictive variables, in flow regionalization studies. The study area considered was the hydrographic basin of the Paranaíba River. Flow data from streamflow gauges present in the study area and precipitation data obtained from rain gauges were used, which were interpolated by the simple kriging method, the TRMM satellite and WorldClim. The study area was divided into four homogeneous regions, and only for region 4 the generated regionalization equations have some use restriction, since some adjustments proved to be unsatisfactory. The best fits of the regionalization equations were obtained using the precipitation data from the rain gauges interpolated by simple kriging, however, the use of precipitation data from TRMM and WorldClim as predictive variables of the flow provided similar results. Therefore, it can be considered that the alternative databases (TRMM and WorldClim) used in the study are presented as an option to replace the data observed in the rain gauges, resulting in a gain of time by the researchers and management bodies in the studies of flow regionalization. • The potential regression model was the one that presented the best results. • WorldClim and TRMM had good performance in the analysis. • Interpolated data had the best results for streamflow regionalization. • WorldClim and TRMM are a promising alternative for streamflow regionalization. [ABSTRACT FROM AUTHOR]