Oregon State University’s Chris Goldfinger has doubts. “The earthquake is the warning,” said Goldfinger, a marine quake expert who happened to be in Japan when last month’s devastating quake and the ensuing tsunami struck.

But physicist Jörn Lauterjung, who has been working on such systems since the 2004 Indian Ocean tsunami, believes Japan’s history of seismic preparedness – including warning systems – prevented even more lives from being lost.

Near-shore quakes pose very different risks than distant ones, and the March 11 disaster illustrated the point. Despite tsunami warnings that went out within three minutes of the quake, coastal Japanese had only about 10 minutes to get to higher ground – and in some cases, that wasn’t high enough to escape the onrushing water. Coastal Oregonians, by contrast, had hours after being warned to evacuate, and by the time the wave made its way across the Pacific, it was small enough to do damage only to selected harbors.

Reverse the situation, though, and the US coast could have as little time to react as did the Japanese. Tsunami preparedness educators emphasize that point: If you’re on the coast and the ground shakes, don’t wait for a warning – or anything else – before moving to higher ground.

Read more about the issues and technology  in Scientific American: Make Or Breaker: Can a Tsunami Warning System Save Lives During An Earthquake?