Hydrological Model Calibration Strategy for Climate Change Impacts Study

Hydrological models require calibration to provide accurate simulation, and the calibration usually often requires long-term historical hydrometeorological data. The calibrated parameters obtained from historical data are assumed to be stationary. However, the stationary assumption for the para terms in the hydrological modeling may not be appropriate for the future climate, especially in a changing climate. This study aims to explore different approaches to minimize this issue by comparing calibration frameworks and offer alternative strategies to improve model robustness for climate change impact studies. The optimization strategies consider nonstationarity in the model parameters associated with different climate regimes and provide a functional form with dynamic climate predictors to better represent abnormal climates informed by a set of climate change scenarios over South Korea.