Thirty-six hours? I had no idea. I thought harbors were supposed to be havens.

The word tsunami is Japanese for harbor wave, and many times the worst physical damage comes once the waves enter the confines of a harbor, said Costas Synolakis, professor of civil and environmental engineering and director of the Tsunami Research Center at the University of Southern California.
"It looks like what happens if you hit a drum," Synolakis said. "You create waves with just one hit to it, but the drum keeps vibrating. What that means is it takes a couple waves to come in. Then you set up these back and forth waves inside the harbor that end up reinforcing each other. Crescent City took about
36 hours for the oscillation to die down."
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