Why Did That Shindo 3 Feel Stronger? Earthquakes Jolt Western Japan and Kyushu, Sparking Anxiety

Shortly after 8:30 PM on March 25th, a series of earthquakes struck Western Japan and the Kyushu region, with a maximum seismic intensity of Shindo 3 observed across a wide area. On social media (formerly X), numerous comments like "It felt much stronger than Shindo 3" and "It felt like Shindo 5" surfaced, indicating that many residents were surprised by the intensity of the shaking and grew increasingly anxious.

According to weather information company Weathernews, at approximately 8:31 PM on the 25th, an earthquake registering Shindo 3 was observed in northern Kyoto Prefecture, southeastern Hyogo Prefecture, southwestern Hyogo Prefecture, and Awajishima in Hyogo Prefecture. Subsequently, at around 8:33 PM, another earthquake with a Shindo 3 intensity occurred in the Chikugo region of Fukuoka Prefecture. In response to these consecutive tremors, comments such as "It's crazy that Kansai and Kyushu were hit by Shindo 3 one after another" and "What's with different places shaking just minutes apart?" expressed surprise at this unusual pattern of events.

Despite being announced as Shindo 3, many residents in wide areas including Amagasaki City and Nishinomiya City in Hyogo Prefecture, and Fushimi-ku in Kyoto City, reported feeling "like a Shindo 4 because I'm in an apartment," "significant shaking with a rumbling sound," and "honestly, it shook quite a bit for a Shindo 3." A considerable number of people braced themselves for shaking stronger than the official announcement. There were also comments from those who recalled the Kumamoto earthquakes, and others who, having experienced the Great Hanshin-Awaji Earthquake, were able to react calmly to the recent tremors, illustrating how perceptions can differ based on region and individual experience.

Specific damage reported due to the shaking included temporary suspension of JR train services, as well as posts like "I'm scared objects will fall over from the earthquake" and "my decorative CDs almost shattered." There were also reports of pets, such as dogs, freezing up, indicating that the tremors affected animals as well as humans.

Many residents are urging caution regarding aftershocks, expressing anxiety about future conditions with comments like "I'm worried it might shake again" and "we shouldn't let our guard down." Experts continue to advise vigilance regarding future seismic activity and urge people to heighten their daily disaster preparedness, such as securing furniture and confirming evacuation routes.

The Context

For non-Japanese readers, understanding the Shindo scale is crucial. Unlike the Richter or moment magnitude scale, which measures the total energy released by an earthquake, the Shindo (seismic intensity) scale measures the degree of ground motion and its effects at a specific location. A Shindo 3 earthquake is generally considered minor; most people indoors would feel it, and hanging objects might swing, but damage is rare. However, factors such as being on a higher floor in a building, the local geology, or individual sensitivity can significantly alter how a tremor is perceived. Many residents' experience of feeling the Shindo 3 quakes as stronger than officially reported is not uncommon in earthquake-prone Japan. References to past major earthquakes like the Great Hanshin-Awaji Earthquake (1995) in Kobe and the Kumamoto Earthquakes (2016) highlight the collective memory and heightened awareness of seismic activity among the Japanese population. Japan frequently experiences earthquakes due to its location on the Pacific Ring of Fire, leading to a strong culture of disaster preparedness.