"Probabilistic Tsunami Hazard Assessment"
Randall J. LeVeque
Applied Mathematics Department
University of Washington
Probabilistic Tsunami Hazard Assessment (PTHA) for a coastal community or harbor can be performed by running a tsunami propagation/inundation code with initial seafloor deformations sampled from some presumed probability distribution of possible earthquakes. Standard approaches use logic trees developed by consensus among seismologists but an alternative is to generate stochastic realizations based on the expected spatial correlation of slip on a fault plane, e.g. using Karhunen-Loeve expansions. In addition to uncertainty in the tsunami source, tidal uncertainty has to be incorporated since the effect of a tsunami can be very different depending on the tide stage when waves arrive. Some new approaches will be discussed and illustrated in relation to a recent probabilistic study of Crescent City, California.
Host: Kyle Mandli