2025年12月8日深夜，日本本州東部附近海域（北緯41.00度，東經142.35度）發生一起規模7.5的強烈地震，震源深度約50公里。地震造成多人受傷，並有超過十萬名居民被迫緊急避難。此次地震的震央位於日本海溝與千島海溝交界的北太平洋近海區域，與2011年東日本大地震的震源域相鄰。地震引發日本氣象廳與相關部門的高度警戒，社會各界隨即進入緊急防災狀態。

在地震發生後的12月9日凌晨2點，日本氣象廳發布針對北海道及三陸沿海地區（青森縣、岩手縣、宮城縣）的第二次地震警報，提醒未來一周內發生8級以上大地震的可能性有所上升，從平時的0.1%提高至1%。這是自2022年12月日本啟用特大逆衝型地震預警系統以來，氣象廳首次針對大規模地震發布預警。根據預警報告，如果未來真的發生里氏9級地震，日本海溝沿岸最多可能造成約19.9萬人死亡，而千島海溝沿岸則可能造成約10萬人死亡。

此次預警特別針對北海道及日本東北地區北部的太平洋近海區域，也就是日本海溝與千島海溝的銜接處。日本氣象廳評估，該區域未來一周內可能發生最大震級達9級的巨大地震。日本地震調查委員會更指出，再次發生強震的“緊迫性極高”，呼籲社會提高防災警覺。根據全球大規模地震的統計數據，震級7級或以上地震發生後的一周內，再次出現8級或以上地震的概率約為1%，明顯高於平常水平。

對此，日本內閣府參事官森久保司表示，雖然目前尚無法確認是否會發生大地震，但民眾需比平時更加小心謹慎。他強調，社會與經濟活動可繼續進行，但防災警戒不可放鬆。在災後避難的現場，岩手縣釜石市釜石東中學體育館成為當地居民的臨時避難中心。一名32歲的居民表示，即便海嘯警報已解除，他仍與家人留在避難中心，因為擔心餘震可能帶來的危險：“我睡不好，孩子們也坐立不安。而且地震預警也發布了，所以我們不能放鬆警惕。”另一位57歲的家庭主婦則坦言，對未來可能發生的大地震感到焦慮，幾乎無法入睡：“想到未來可能會發生大地震，就覺得很可怕。我想做好準備，以便隨時可以撤離。”

整體而言，這次7.5級地震不僅造成即時的受災和避難需求，也引發日本氣象廳前所未有的高級別地震預警，提醒民眾啟動“特別備災模式”，隨時應對可能出現的9級地震風險，展現了日本在面對多發強震區域時的防災高度警覺性。

On the night of December 8, 2025, a powerful magnitude-7.5 earthquake struck the offshore area near eastern Honshu, Japan (latitude 41.00° N, longitude 142.35° E), with a focal depth of approximately 50 kilometers. The quake caused multiple injuries and forced over 100,000 residents to evacuate. The epicenter is located in the northern Pacific offshore region, at the junction of the Japan Trench and the Kuril Trench, adjacent to the source area of the 2011 Great East Japan Earthquake. The earthquake immediately prompted heightened alerts from the Japan Meteorological Agency (JMA) and other relevant authorities, putting society on high alert for disaster preparedness.

In the early hours of December 9 at 2:00 a.m., the JMA issued a second earthquake advisory for Hokkaido and the Sanriku coastal regions, including Aomori, Iwate, and Miyagi Prefectures. The advisory warned that the likelihood of an earthquake of magnitude 8 or higher occurring within the next week had increased from the usual 0.1% to 1%. This marks the first time the JMA has issued a large-scale earthquake warning since activating its special megathrust earthquake warning system in December 2022. According to the advisory, if a magnitude-9 earthquake were to occur, the Japan Trench coastline could see as many as 199,000 deaths, while the Kuril Trench coastline could see up to 100,000 fatalities.

The warning specifically targets the offshore areas north of Japan’s Tohoku region, where the Japan Trench and Kuril Trench converge. The JMA estimates that this region could experience a massive earthquake of up to magnitude 9 within the coming week. The Japan Earthquake Research Committee has also noted that the urgency of another strong earthquake is extremely high. Based on global statistical data for large earthquakes, the probability of an earthquake of magnitude 8 or higher occurring within one week after a magnitude 7 or higher quake is approximately 1%, which is significantly above normal levels.

In response, Morikubo Tsukasa, an official from the Cabinet Office, stated that while it is not yet confirmed whether a major earthquake will occur, citizens should exercise greater caution than usual. He emphasized that social and economic activities can continue, but disaster preparedness and vigilance must be maintained.

At the evacuation center set up in the gymnasium of Kamaishi Higashi Junior High School in Kamaishi City, Iwate Prefecture, a 32-year-old resident said that even after the tsunami warning was lifted, he remained in the center with his family due to concerns about aftershocks: “I can’t sleep well, and the children are restless. With the earthquake advisory issued, we can’t let our guard down.” A 57-year-old housewife at the same center added that she was so anxious about the possibility of a future major earthquake that she could hardly sleep: “Thinking about the potential for a massive earthquake is terrifying. I want to be prepared so we can evacuate at any moment.”

Overall, this magnitude-7.5 earthquake not only caused immediate injuries and evacuation needs but also prompted Japan’s Meteorological Agency to issue an unprecedented high-level earthquake warning. Citizens have been urged to activate a “special disaster preparedness mode” to remain ready for the potential risk of a magnitude-9 earthquake, demonstrating Japan’s heightened vigilance in responding to a region prone to repeated strong seismic events.