Vol. 7, Issue 6, Part A (2025)

Sensitivity analysis is crucial for model parameterization, optimization, calibration, and uncertainty quantification. It is generally classified into two types: global techniques where variation of all parameters took place simultaneously and local technique where at a time one parameter will change. In this study two methods were employed to find the most sensitive parameters and the sensitive parameters based on their ranking were identified and can be used for calibration. The results indicated the most sensitive parameter as base flow alpha factor (Rank 1). The main channel’s effective hydraulic conductivity (Rank 2) was found out to be second most sensitive parameter. The third and fourth sensitive parameters were found to be Curve number and depth measured from soil surface to bottom of layers respectively. The fifth, sixth and seventh most sensitive parameters were found out to be surface lag coefficient, deep aquifer percolation fraction, and soil evaporation compensation factor respectively. This study concluded that finding out the most sensitive parameters make the calibration easy by reducing the effort involved in it.