Aplicación de los modelos lluvia-escorrentía GR2M y GR4J en la cuenca del Río Gualí para la gestión de los recursos hídricos

Abstract

The objective of this project was to evaluate the applicability of the hydrological rainfall-runoff models GR2M and GR4J to determine the daily and monthly flows. This evaluation was made taking as a study area the basin of the Guali river located in the north of the department of Tolima, with the purpose of helping to solve the problems that appeared in this basin, for not having enough information in its stations. thats why we determine the efficiency of the hydrological models, having this information and adjusting this to the conditions of the evaluated basin, we can finally determine if the GR2M and GR4J models are efficient to apply them in Colombia we made a hydroclimatological analysis programmed in the software PYTHON, to get to determine the quality of the available climatological data and at the same time to make a purification and reclassification of the climatological stations, to obtain a complete database that would make the models more efficient. After this, both models were calibrated having the data of precipitation and potential evapotranspiration, said evapotranspiration was calculated by the thornthwaite method.

After this the two models were executed with the correctly calibrated data, to achieve this we used a PYTHON programming language and the Excel pages programmed by CEMAGREF (Center for Agricultural Research and Environmental Engineering of France), which helped to make the models even more efficient, in terms of execution time. According to the results obtained with the modeling, it was observed that the GR2M model shows an efficiency in the calibration stage according to the Nash criterion of 67% and 79.1% in the stage of validation that indicates that the GR2M model was adjustable in the Guali River basin. For the GR4J model, an efficiency in the calibration stage of 76.2% and in the validation stage of 80% is obtained, which indicates that the The model is applicable and adjustable in the Guali River basin. Finally we can conclude that these models are of great importance and impact because with only data of precipitation, evapotranspiration and flows, we can achieve an optimal and effective process, in this way we obtain better approximation between the estimated and observed flows. Finally, it is recommended to apply this type of models in the basins in Colombia that present this problem for not having enough data available in their monitoring stations.