HYDROLOGICAL MODEL WITH IMERG IMAGES OF THE COAHUAYANA RIVER BASIN, JALISCO, MEXICO

Abstract

Hydrologic modeling using precipitation estimated from satellite images considers temporal and spatial variability of the precipitation. The objective of this study was to model the rain-runoff process and calibrate some hourly hydrograms from the Coahuayana River Basin in Jalisco, Mexico. IMERG version 6 satellite rainfall images during the maximum events occurred in July 2010, October 2011, September 2013, October 2015, and August 2021 were used. The basin is located in the states of Jalisco, Colima, and Michoacán, and covers an area of 7332 km². The hydrologic model was developed using the program HEC-HMS and calibrated at the CONAGUA hydrometric station Callejones. The methods used for the calculations are the runoff curve number and Clark’s modified unitary hydrogram. The results obtained in three of the five events were satisfactory: the Nash-Sutcliffe coefficient (NSE) oscillated between 0.39 and 0.77, and R² oscillated between 0.51 and 0.86. We concluded that the integration of an hourly hydrologic model with IMERG-L satellite rainfall images is a good option in areas where hourly rainfall data measured on land is scarce or non-existent.