Advancing research in cold regions hydrology to support the modeling and mapping of ice-induced flood inundation

Northern regions in the US are regularly impacted by river ice-induced flooding events especially during the annual breakup period in spring. River ice grows in extent and thickness during winter in northern rivers. The presence of river ice alters streamflow and may lead to ice jams that reduce water level downstream which may undermine drinking water intake. River ice may also increase water level upstream and cause major flooding. Therefore, to protect northern communities against these repetitive ice-related hazards, it is essential to develop the right tools to monitor river ice and its dynamics as well as the possibility of ingesting river ice information in models to better forecast streamflow in presence of ice.

The goal of this project is to advance NOAA’s current capabilities in the field of cold regions hydrology by enhancing the modeling and mapping of ice-induced flood inundation in northern regions. To this end, three main objectives are defined. First, an operational system for river and lake ice mapping and monitoring across the US will be developed. Then, the work will cover the development of a system to assess the risk of ice-related flood inundation that relies on the analysis of historic records. In addition, the modeling of the ice formation and breakup in rivers will be modeled to simulate the impact on streamflow and flood inundation.

The method consists of blending moderate and high-resolution satellite data across the US to map ice in large and narrow rivers. The analysis of four decades of satellite images will lead to the determination of ice phenology and the link between the prevailing surface and meteorologic variables and the occurrence of ice-related flood inundation. The relationship between ice onset and breakup dates and the likelihood of flood inundation occurrence will be used to build an alert system that determines areas with high risk of ice-related flood inundation. The project will also cover the simulation in the NWM of ice formation through a static thermodynamic process which will be conducted through the introduction of radiative transfer modeling and the determination of supercooled section of rivers which leads to frazil and anchor ice formation. Future work will address the transport of ice and the complex interaction with river hydraulics.

This project will introduce a new multi satellite-based system for river ice monitoring. Another novel contribution consists of the introduction of new schemes in the NWM for the modeling of thermodynamic and static ice formation and its impact on streamflow. The proposed river ice and ice-flood inundation mapping and forecast systems and the anticipated improvement in the forecast of streamflow in northern watersheds support NOAA’s mission to understand and predict changes in climate, weather, ocean, and coasts.