Developing Next Generation of the Great Lakes Coastal Forecast Modeling System

Coastal infrastructure in the Great Lakes supports commercial navigation, flood preparedness, recreation, and natural resource management. The NOAA Great Lakes Operational Forecast System (GLOFS), based on the Finite-Volume Community Ocean Model (FVCOM), provides forecast guidance throughout the Great Lakes. These models have traditionally treated shorelines as static boundaries, and many ports, harbors, estuaries, and floodplains are unrepresented in the model domain. The next generation of Great Lakes modeling systems seeks to extend model coverage to include these critical coastal features, and to bridge the land-water interface by coupling the hydrologic and hydrodynamic domains. With funding from the Bipartisan Infrastructure Law, we have expanded the GLOFS model grid, starting with Lake Ontario, to include the surrounding floodplain, adding harbors and ports that are not included in the current operational model. The updated model (SCHISM) is coupled to streamflow simulations from the National Water Model (NWM), with simulations validated against observed high water events. Simulations of surface temperatures, coastal water levels, and thermal stratification are significantly improved over the previous model generation, especially in nearshore regions where grid resolution has been increased substantially (e.g. 200m to 50m). This updated model provides much needed flood and inundation guidance in flood prone regions, including economically important harbors, ports, and bays. One example is Sodus Point, New York, a flood prone bay that was not included in the previous operational model. We are currently working with stakeholders to identify additional regions of interest on Lake Ontario that could benefit from improved flood and inundation guidance.