The Japan Meteorological Agency lifted all tsunami advisories for the Pacific coast on Monday after a major earthquake struck off the Philippines [1].
The cancellation ends a period of high alert for coastal residents from the Kanto region down to the Amami and Okinawa islands. While the immediate threat has subsided, the agency said that sea-level fluctuations may continue to affect the shoreline.
The advisories were triggered by a magnitude-8.2 earthquake [3] that occurred on the morning of June 8. The seismic event caused significant casualties in the Philippines, where 19 people died and 134 others were injured [7].
Monitoring stations across Japan recorded varying levels of sea-level changes. At Miyazaki Port, officials observed a tsunami height of 30 cm [5]. Meanwhile, a height of 20 cm was recorded at Chichijima [6].
Government officials lifted the advisories in the late afternoon. Reports on the exact timing vary slightly between 4:46 p.m. and 4:50 p.m. JST [4].
Despite the lifting of the formal warnings, the Japan Meteorological Agency said the public should remain cautious. The agency said residents should continue monitoring sea-level changes as the ocean stabilizes following the massive displacement of water caused by the quake.
“19 people died and 134 others were injured”
The rapid issuance and subsequent lifting of these advisories demonstrate Japan's highly integrated early-warning system for trans-oceanic seismic events. Because a magnitude-8.2 quake can displace massive volumes of water, the risk remains high even for distant coastlines. The continued warning regarding sea-level fluctuations highlights that 'tsunamis' are not always single waves but can be a series of irregular surges that persist long after the initial alert is canceled.
