Japanese public urged to stay vigilant after quake advisory ends

Following a powerful earthquake that struck off the east coast of Aomori Prefecture, part of the Tohoku northeastern region, on December 8, the agency issued what it calls a subsequent quake advisory warning of a possible further quake off Hokkaido and the Sanriku region from northern to northeastern Japan.

The December 8 temblor registered upper 6, the second-highest level on Japan's seismic intensity scale, in the Aomori city of Hachinohe, and tsunamis of up to 70 centimeters were observed in many coastal sites.

"Although the period of special preparations, such as staying ready to evacuate immediately, has ended, we hope people will remain prepared as much as possible for a major quake that could occur at any time," Yosuke Igarashi, a planning official at the Cabinet Office, said at a press conference.

Regarding the public reaction to the first-ever announcement of the subsequent quake advisory since the December 2022 introduction of the system, Igarashi said, "People generally accepted it calmly without much confusion."

"We will conduct a survey at an early time asking local governments and businesses in areas covered by the advisory about what actions they took and what problems they had," he said, adding, "We will then consider whether we can make any improvements (in the subsequent quake advisory system)."

Kiyoshi Takeda, head of the meteorological agency's Office of Large-scale Earthquake Analysis, said at the same press conference that seismic activity off the east coast of Aomori is "declining, but remains higher than usual and is expected to continue for a while."

"According to the long-term assessment by the (government's) earthquake research committee, there is a high probability of a major earthquake occurring along the Chishima-Japan trench system (in the Pacific) within 30 years," Takeda added, urging people to remain prepared.