Be alert, prepare for aftershocks following powerful earthquakes

Strong tremors hit large areas of the Tohoku and Kanto regions late at night. Residents need to be vigilant as another major earthquake could occur in the next few days.

Shortly after 11:30 p.m. on Wednesday, an earthquake occurred with its focus off the coast of Fukushima Prefecture. Tremors in parts of Fukushima and Miyagi prefectures measured upper 6 on the Japanese seismic intensity scale — which tops out at 7. Also, a 30-centimeter tsunami was confirmed in Ishinomaki, Miyagi Prefecture.

There were deaths and numerous injuries. Cracks appeared in the Tohoku Expressway and many buildings were damaged. The 2011 Great East Japan Earthquake must have been in the minds of many people.

In Miyagi Prefecture, a Tohoku Shinkansen bullet train derailed while in operation. This is the second time a Shinkansen train carrying passengers has derailed. In 2004, the Joetsu Shinkansen derailed while carrying passengers during the Niigata Prefecture Chuetsu Earthquake. No passengers were injured on Wednesday, but the situation could have been catastrophic.

Since the Chuetsu earthquake, measures have been taken to prevent derailments on Shinkansen lines. This time it was fortunate that the train happened to be close to the station where it planned to stop and had been slowing down when the earthquake struck.

It is expected to take some time to resume operations. East Japan Railway Co. should thoroughly investigate the cause of the derailment and utilize its findings in countermeasures.

Following the issuance of a tsunami advisory, coastal municipalities issued evacuation instructions. Many residents rushed to shelters, but many others might have been reluctant to evacuate in the middle of the night.

It is important to check routes to evacuation centers on a regular basis in anticipation of night evacuations. Also, municipalities should conduct drills with nighttime disasters in mind.

More than 2 million households in Tokyo and other areas were without power. Traffic signals in downtown areas lost power and police officers were on duty at intersections to manage the traffic. Some people were also trapped in elevators. If the earthquake had occurred during the daytime, there would have been even more disruptions.

It is important for each municipality to examine the damage caused by the earthquake and reflect their findings in local disaster prevention plans.

The earthquake is believed to have occurred within the Pacific plate that dips beneath the continental plate, moving from the ocean side to the land side. Because the focus of the earthquake was closer to land and deeper than that of the Great East Japan Earthquake, strong tremors were felt over a wide area.

The area has always been seismically active, and the effects of the Great East Japan Earthquake have not yet subsided. It is essential to remain vigilant for earthquakes of this severity.

The earthquake on Wednesday might have loosened the ground in some places. If aftershocks occur, landslides and avalanches are possible. It is important not to let your guard down.

In recent years, major natural disasters such as earthquakes and typhoons have occurred one after another in various regions. People should take a fresh look at whether they are adequately prepared.

(From The Yomiuri Shimbun, March 18, 2022)