Modeling of Ice-jam Flooding: Integrating SUMMA with River Ice Processes for Climate Change Impacts

Ice-jam flooding linked with the interactions of hydrological and cryosphere processes is a serious threat to riverine communities in cold regions. This work uses the coupling of the Structure for Unifying Multiple Modeling Alternatives (SUMMA) hydrological model, which represents a wide range of hydrological processes, and the mizuRoute river routing model with that of a river ice model (i.e., RIVICE model) to project of ice-jam floods under changing climatic conditions. In fact, SUMMA and mizuRoute simulate streamflow, which is then passed to RIVICE to model ice formation and dynamics. The dynamics of streamflow simulated by SUMMA / mizuRoute include comprehensive representation of various hydrological processes, while the RIVICE model considers the processes of ice formation, frazil ice dynamics, and accumulation. This coupled modeling framework is applied to the Klondike River in Yukon, Canada, one of the regions historically affected by ice-jam flooding. This study uniquely integrates these models to enable projection of future ice-jam flood scenarios. The simulations are driven by climate projections from the CMIP6 datasets, enabling comprehensive assessments of future freeze-up events and associated flood risks at high spatial and temporal resolution. This work contributes to the increasing value of integrated hydrological and cryospheric modeling, improving flood risk assessments and informing adaptive strategies, such as improved forecasting systems and infrastructure design, for community protection in cold regions.