An approach to measure parameter sensitivity in watershed hydrological modelling

Area of Science:

• Hydrology
• Environmental Science
• Water Resource Management

Background:

• Hydrological responses are influenced by watershed characteristics, exhibiting spatial and temporal variability.
• Accurate hydrological modeling is crucial for understanding and managing water resources.
• Previous hydrological models were developed for the Little Miami River (LMR) and Las Vegas Wash (LVW) watersheds.

Purpose of the Study:

• To conduct detailed sensitivity analyses of previously developed hydrological models for the LMR and LVW watersheds.
• To compare the relative sensitivities of hydrological parameters between the two distinct watersheds.
• To develop and apply an approach for measuring parameter sensitivities across different flow regimes.

Main Methods:

• Utilized hydrological models previously developed for the Little Miami River and Las Vegas Wash watersheds.
• Employed normalized root mean square error (NRMSE) to quantify and compare parameter sensitivities.
• Integrated NRMSE with flow duration curve analysis to assess sensitivities under various flow conditions.

Main Results:

• Groundwater-related parameters demonstrated high sensitivity in the LMR watershed.
• The LVW watershed exhibited primary sensitivity to near-surface and impervious parameters.
• High and medium flow regimes were generally more influenced by most parameters, while low flows were sensitive to groundwater parameters.

Conclusions:

• The study identified distinct hydrological parameter sensitivities between the LMR and LVW watersheds.
• The developed approach effectively measures parameter sensitivities across different flow regimes.
• The methodology aids in facilitating hydrological model development and calibration processes.