Modeling Future Flooding Extremes to Explore Unidentified Risks in the Arctic

Abstract:

Reducing risk to communities and infrastructure depends heavily on the ability to understand the frequency and intensity of regional natural hazards. In the Arctic and near-Arctic, where temperature and precipitation regimes are changing on a compressed timeline, the temporal scale of events shift, and historical norms no longer help to define the upper boundaries of risk. To understand how future extreme events may change as a result of climatic shifts, it will require modeling the extreme conditions of future climate scenarios produced by global circulation models. While it is impossible to predict specific events years or decades out with high accuracy, representative extreme events from climate models can be used to simulate the potential impacts and stressors on a system or community that has not yet experienced those events.

This effort focuses on exploring how flooding in interior Alaska, on the Chena river, could potentially shift under future climate conditions where precipitation in the area is expected to increase dramatically over the next several decades. The Chena River is currently one of the better instrumented and observed river systems in Alaska, and a significant number of interior Alaska residents are within its area of impact. While the majority of the Fairbanks community is protected by the Chena Flood Control Project and Moose Creek Dam, this system was designed under a substantially different precipitation regime. By exploring how the projected increase in precipitation is likely to translate to streamflow, flood frequency, and flood extent for this system, it allows risk related research to explore how current planning efforts could consider future climate based hazards to reduce risk to communities and improve planning and decision making efforts. This work will help to provide a framework for assessing future risk in northern areas within other Arctic river systems.