Japan is bracing for a once-in-a-century earthquake. Does it need to?

Tokyo CNN —

As tremors shook the ground in parts of western Japan last Thursday, local and national government bodies leapt into action.

Meteorologists gathered and issued a temporary tsunami advisory. A special committee warned that another “major earthquake” could hit in the coming week – the first time in its history the body had issued this type of nationwide advisory. High-speed trains slowed down as a precaution, causing travel delays, and the country’s prime minister canceled his overseas trips.

In the end, the government lifted most advisories and reported no major damage from the 7.1-magnitude quake. But much of the country remains on high alert, preparing for a potential emergency during what is normally peak travel season during summer holidays – reflecting Japan’s laser-focus on earthquake preparedness.

However, some experts have cast doubt on whether such an advisory is necessary, or even accurate – and whether it risks pulling resources away from communities deemed lower risk.

Japan is no stranger to severe earthquakes. It lies on the Ring of Fire, an area of intense seismic and volcanic activity on both sides of the Pacific Ocean.

“Japan sits on the boundaries of four tectonic plates, which makes it one of the most earthquake-prone areas in the world,” said Shoichi Yoshioka, a professor at Japan’s Kobe University.

“About 10% of the world’s earthquakes of magnitude 6 or higher occur in or around Japan, so the risk is much higher than in places like Europe or the eastern United States, where earthquakes are rare,” Yoshioka said.

Residents pass through a devastated street in Ishinomaki, Miyagi prefecture, after Japan was hit by a devastating earthquake and tsunami, on March 15, 2011.

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