In order to establish a baseline, a SWAT model was run using default parameters for each BC SPD of GPM, PERSIANN, CHIRPS, and CMORPH for the period 2000–2013 on a daily basis, including a two-year warm-up period (2000–2001). The default values of parameters were derived from the Food and Agriculture Organization (FAO) Global Map of land cover and soil characteristics (Abbaspour et al. 2004, 2007). Hereafter, a calibration process was performed using SUFI-2 in SWAT-CUP on the results based on default values to make them more comparable with the observed values. The model was calibrated and validated using daily Jhelum River flow data from January 2002 to September 2010 and October 2010 to December 2013 at A-pattan station, respectively. For the calibration of the sensitive parameters, 22 frequently used streamflow calibration parameters were selected through an extensive literature review close to the study area (Abbaspour et al. 2015; Babur et al. 2016; Saddique et al. 2019, 2022; Shahid et al. 2021; Rahman et al. 2022). In SWAT-CUP, a Global Sensitive Analysis (GSA) was applied to select the most sensitive parameters for streamflow. Hence, 28 parameters were considered for the sensitivity analysis, out of which 8 parameters were found to be the most sensitive to streamflow in the calibration phase based on maximum t-test values and minimum p-values, as shown in Table 5. Based on these most critical parameters, SWAT-CUP was run three times with 1,000 simulations each time to calibrate streamflow and to narrow down parameter ranges at every step (Table 5). Detailed information on the calibration procedure of the model can be found in Abbaspour et al. (2015).