Japan is probably the most prepared nation on earth for earthquakes and tsunamis. From what I understand, they have a well organized emergency response system, and regularly do drills. You will have noticed the alert sirens and the guys in helmets directing people. I think the authorities in Japan have pre-designated and marked many buildings that are stout enough to serve as a refuge from tsunamis. We in the US have a long way to go to be as prepared as Japan.

If you understand what is happening, and have thought about and practiced your response, you are much more apt to remain calm in an emergency. One of my all time favorite quotes:

"People don’t rise to the occasion. They default to their training." -Attributed to Rick Rescorla, who was a former soldier who had become a coporate security officer. Due to his planning and training drills, all but six of the 2,700 Morgan Stanley employees survived the the attack on the World Trade Center on Sept. 11, 2001.