Regionalização de parâmetros do modelo de grandes bacias MGB

Abstract

Regionalization is a methodology that allows the transfering of information from a watershed with hydrological data monitoring to an ungauged watershed, and is usually applied to determinate hydrological variables or functions for pratical applications in hydrological studies and projects. Despite the conventional use of regionalization to estimate hydrological variables and functions, theres is an increasing use of hydrological models in regionalization process, mainly from the PUB (Predictions at Ungauged Basins) initiative, established by the International Association of Hydrological Sciences (IAHS). This metodology consists in determinate the empirical parameters from an hydrological model in ungauged regions through the regionalization process, instead of the usual application of these models where these parameters would be determinated by calibration. Regionalization of hydrological model parameters has been widely applied worldwide, showing a huge potential for estimation of flow data series at ungauged regions in works like Parajka et al. (2005), Gitau e Chaubey (2010), Li et al. (2018), Yang et al. (2018) e Pagliero et al. (2019). According to the literature, the regionalization of hydrological model parameters can be splited in 2 characteristic groups: regression regionalization method, and parameter transfer method. This study applied the regionalization of hydrological model parameters method using the MGB model. As the purpose of evaluating this method results, the study did a cross validation, using 6 gauged hydrological basins: Itapemirim, Itabapoana, Piranga, Santo Antônio, Pomba e Paraibuna. Five regionalizations scenarios were compared, each one with a different approach for MGB model parameters determination. According to the results, the parameter transfer methods proved more efficientes than the linear regression method, and the results validation pointed that the parameter regionalization method have a huge pontential to application in ungauged watersheds.