Impact of precipitation on parameter sensitivity and identifiability in the variable infiltration capacity (VIC) model

This study aims to explore the interaction between selected gridded precipitation products and parameters of the variable infiltration capacity (VIC) model within the Gharesu basin in Iran. The evaluation is done in two phases: (1) exploration of the performance of various precipitation products (i.e. three satellite gauges, two reanalyses, and three gauge-based datasets), and comparison to station measurements; and (2) the interaction of behavioural VIC parameter sets with these precipitation products. Evaluation of best-performing and non-dominant solutions indicates that for most VIC parameters, no unique value and range can be specified for the precipitation products. This reflects the important fact that precipitation, which is known to carry significant information, is decisive in inferred values of parameters that are perceived to have physical meaning (e.g. soil characteristics). In summary, our research contributes to a deeper understanding of the complex relationship between precipitation products and parameters of hydrological models.