Forecasting glacial floods to protect communities

Outburst floods are nothing new to glaciologists. For years, researchers have known the potential hazard that forms when glacier movements create ice-dammed basins, trap meltwater, and pool into large reservoirs. Recently, however, glacier outbursts have become more devastating to their surrounding communities, releasing increasing water levels year after year. In 2024, a flood in Juneau, Alaska broke records for the second year in a row, displacing residents, eroding landscapes, and destroying homes.

To better understand these phenomena, the National Science Foundation is funding a team of researchers to focus on better understanding and estimating an annual outburst flood that affects Juneau as well as develop large-scale flood hazard models to improve glacial flood forecasts and identify future outburst hazards across northwest North America. Using field and remote sensing data, the study will produce physically based models of glacier evolution and outburst floods to identify and quantify how flood hazards will continue to change. 

“Understanding glacier retreat and its effects on outburst floods is critical for mitigation and adaptation,” said David Rounce, assistant professor of civil and environmental engineering and co-principal investigator on the project. “Improving our flood prediction models will help communities develop effective early warning systems and adaptation strategies.”

The study centers on the Juneau-based Áak’w T’áak Glacier (Mendenhall Glacier), which regularly produces outburst floods that have been monitored since 2011, including the 2024 disaster. While the team will conduct its fieldwork there, they will use models to investigate changes in hazards for all of Alaska and western Canada. Alaska’s diverse landscapes and climates reward researchers with data that is widely applicable, including to regions like High Mountain Asia, where they experience similar glacier flood threats. Subsequently, researchers are optimistic that the knowledge gained could be useful for better understanding changes in hazards globally. 

 

Improving flood prediction models will help communities develop effective early warning systems and adaptation strategies.

David Rounce, Assistant Professor, Department of Civil and Environmental Engineering

"As glaciers continue to change, understanding and predicting their impact on communities becomes more crucial," explained Rounce. "Our goal is to enhance current flood forecasting models, helping communities better prepare for and respond to the growing threat of glacier outburst floods."

This five-year project is led by the University of Alaska Southeast and conducted in collaboration with the State of Alaska Department of Geological & Geophysical Surveys.