TSUNAMI INUNDATION MAPS FOR JUNEAU, ALASKA.

In this report we evaluate potential tsunami hazards for the southeastern Alaska community of Juneau and numerically model the extent of inundation from tsunami waves generated by tectonic and submarine landslide sources. We calibrate our tsunami model by numerically simulating the 2011 Tohoku tsunami at Juneau and comparing our results to instrument records. Analysis of calculated and observed water level dynamics for the 2011 event in Juneau reveals that the model underestimates the observed wave heights in the city by a factor of two, likely due to complex tsunami-tide interactions. We compensate for this numerical underestimation by doubling the coseismic slip of the hypothetical tsunami sources in our models. Potential hypothetical maximum credible tsunami sources include variations of the extended 1964 rupture and megathrust earthquakes in the Prince William Sound and Alaska Peninsula regions. Local underwater landslide events in Lynn Canal, in Favorite, Saginaw, and Gastineau channels, and in Taku Inlet are also considered as possible tsunamigenic scenarios. The results show that the maximum predicted wave height in the Juneau area resulting from a tectonic tsunami is 2-3 m (6-10 ft), while a landslide-generated tsunami may cause a run-up of 15-16 m (49-52 ft) along the Fritz Cove shoreline and potentially flood portions of the airport. Results presented here are intended to provide guidance to local emergency management agencies in tsunami inundation assessment, evacuation planning, and public education to mitigate future tsunami hazards. [ABSTRACT FROM AUTHOR]