Researchers aim to improve coastal storm surge forecasting

Collaborative report, depending on how well models perform, will be out in a year or two

As winter approaches every year residents of coastal western Alaska brace for severe storms, relying on weather forecasters to give them adequate warning in isolated communities, where sudden storms have caught many off guard and at times led to death.

Now the Alaska Ocean Observing System (AOOS) in Anchorage is collaborating with other researchers to build a coupled storm surge and wave operational forecasting capability for western Alaska.

The collaborative partnership, led by the University of Notre Dame, also includes Axiom Data Science LLC, NOAA’s Great Lakes Environmental Research Laboratory, The University of Michigan’s Cooperative Institute for Great Lakes Research, and the University of Texas at Austin. It is funded by a grant from the Integrated Ocean Observing System.

Notre Dame was awarded a three-year grant for Building Coupled Storm Surge and Wave Operational Forecasting Capacity for Western Alaska.

The ultimate goal of the AOOS modeling advancement effort is to deliver an improved coupled surge, wave and ice forecasting capacity to the NOAA National Centers for Environmental Protection and NOAA National Ocean Service Coastal Survey Development Lab.

“The project is working on effects of multiple factors,” said Carol Janzen, operations manager at AOOS, who holds a doctorate in physical oceanography from the University of Delaware.       “Storm surge is caused by wind affects on water. This model is trying to improve the existing forecast model by adding variables that modify the coastal storm surge.

“It will be a collaborative report,” she said. “Our role is to help them with the data output. The report will come out in a year or two, depending on how well the models perform.”

While there are already storm surge models in existence these models do not contain the complexity necessary to reproduce observed conditions where they exist in much of the Alaska region so existing models need to be modified to more accurately predict storm surge conditions, especially for the less understood coastline of western Alaska, AOOS explains on a website with great deal on the project.

The motivation is there are currently no comprehensive coastal and inshore water level forecasts models for all of Alaska that incorporate tides, storm surge, wind waves and their breaking impact on ice water levels, a high-resolution sea ice model, and the impact of baroclinicity (density stratification).

The wave-surge modelling system being worked on in this project will be utilized for forecasting real time risk assessment for Alaska as a demonstration of improvement to existing forecasts, but this information will not be used immediately for providing forecasts to the public. That process will take some time, as it requires involvement from the national forecast offices.

The wave-surge modeling system can then be utilized for forecasting real time risk assessments for western Alaska communities.

Coastal areas of western Alaska have a complex geography and highly energetic atmospheric and ocean circulation, and wind waves combined with the extensive continental shelf and coastal floodplain leave many western Alaska communities vulnerable to flooding events. Severe winter storms, under varying ocean ice cover make this a uniquely challenging location for predicting and preventing flood-related hazards.

Compounding the situation is the fact that Alaska’s coasts have historically received less attention than those of the continental states, and as a result have a higher degree of uncertainty in terms of coastal water level, current and wind wave simulation capacity and observations. As a result, regional forecasters and the many communities they serve are severely limited in their assessment of the threat from a specific storm event and have no basis to determine impact risk or evaluate safe evacuation routes and locations, researchers said.

The project is getting help meanwhile from researcher Ayumi Fujisake Manome, an assistant research scientist at the University of Michigan’s Cooperative Institute of Great Lakes Research who leads the Great Lakes cryosphere research program at the Cooperative Institute. In an interview with the Cooperative Institute publication Ripple Effect, Manome said that the end product from the project is the coupled surge-wave-ice model for the western Alaska region, with the goal of providing forecast officers with model forecast guidance they can use to issue or not issue warnings and advisories.