Hydrological modeling in a region with sparsely observed data in the eastern Central Andes of Peru, Amazon

Abstract

The Amazon basin is presented in eight South American countries. It is a shelter of great biodiversity from its source in the Andes to its mouth in the Atlantic Ocean. Hydrological research in its headwater region in the Peruvian Andes is affected by the low availability of observed data. In this context, evaluating the applicability of remote sensing hydrological data is an essential alternative for providing background for water resource management. The objectives of this study were i) to evaluate the quality of the Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG) satellite precipitation, ii) to perform hydrological modeling of the Chicllarazo River Basin (CRB) using the Soil and Water Assessment Tool (SWAT) hydrological model based in three precipitation data (observed (OP), satellite (IMERG) and satellite with bias correction (IMERG*)), and iii) to study the hydrological processes in the CRB's sub-basins. The evaluation results of the IMERG dataset based on observed precipitation data showed an underestimation of 25.1%. Comparing the IMERG and IMERG* datasets, correlation coefficients (r) of 0.79 and 0.80, root means square errors (RMSEs) of 55.4 and 49.3 mm, and Kling-Gupta efficiency coefficients (KGEs) of 0.66 and 0.76 were observed, respectively. These results indicate that bias correction in the IMERG data before performing hydrological modeling at the CRB is relevant. In the hydrological modeling, better results were obtained with IMERG*, according to NSE, Pbias, and KGE. The evaluation of the hydrological modeling results in sub-basins was found to be feasible for the study of the hydrological behavior in scarcely monitored regions, like Andes Cordillera.