Japan, a nation synonymous with seismic activity, sits precariously on the Pacific “Ring of Fire,” where tectonic plates converge to produce some of the world’s most powerful earthquakes. The specter of a “megaquake” along the Nankai Trough—a submarine fault stretching 900 kilometers along Japan’s Pacific coast—looms large, with experts estimating an 80% chance of a magnitude 8–9 quake within the next 30 years. This potential disaster, compounded by the cultural phenomenon of a manga prophecy by Ryo Tatsuki, has sparked both scientific scrutiny and public unease. As Japan braces for what could be the world’s heaviest earthquake.
Japan’s Seismic Reality: A Nation on Edge
Japan is no stranger to earthquakes, experiencing approximately 1,500 felt tremors annually. The 2011 Tohoku earthquake and tsunami, a magnitude-9.0 event, killed nearly 20,000 people, triggered the Fukushima nuclear disaster, and caused $360 billion in damages. Since then, Japan has invested heavily in disaster preparedness, but the Nankai Trough megaquake poses an unprecedented challenge. This fault, where the Philippine Sea Plate subducts under the Eurasian Plate, has produced devastating quakes roughly every 100–150 years, with the last major events in 1944 and 1946. Experts warn that the next megaquake could dwarf the 2011 disaster in scale and impact.
In August 2024, a magnitude-7.1 earthquake off Miyazaki Prefecture prompted Japan’s Meteorological Agency (JMA) to issue its first-ever “megaquake advisory,” highlighting a heightened risk of a larger quake in the Nankai Trough. While the advisory was lifted later that month, it underscored the urgency of preparing for a worst-case scenario. A government task force report released on March 31, 2025, estimates that a magnitude-9 quake could result in:
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298,000 fatalities, primarily from tsunamis and building collapses.
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2.35 million buildings destroyed, with seismic intensity reaching the maximum level 7 in 10 prefectures and lower 6 or above in 24.
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Economic losses of ¥270.3 trillion ($1.81 trillion), nearly half of Japan’s GDP, up from a 2012 estimate of ¥214.2 trillion due to inflation and updated flood risk data.
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1.23 million evacuees, or 1% of Japan’s population, with tsunamis up to 34 meters high in areas like Kochi Prefecture.
These figures, while slightly lower than a decade ago due to improved disaster mitigation, remain far from the government’s targets of reducing deaths by 80% and building damage by 50%.
Japan’s Preparedness: A Global Leader, Yet Vulnerable
Japan is a pioneer in seismic resilience, boasting advanced infrastructure and early-warning systems. Key measures include:
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Earthquake Early-Warning System: Since 2007, Japan’s system detects initial seismic waves and issues alerts seconds before stronger shaking, allowing trains to slow, factories to halt, and people to take cover. In 2011, Tokyo residents received a one-minute warning before the Tohoku quake’s intense shaking.
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Tsunami Defenses: Post-2011, Japan constructed a 400-kilometer tsunami wall along its eastern seaboard, designed to delay flooding and buy evacuation time.
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Building Codes: Structures are equipped with dampeners to withstand shaking, and new buildings adhere to stringent seismic standards. However, older structures, particularly in rural areas, remain vulnerable.
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Disaster Drills: By 2024, 86% of municipalities conducted regular drills, up from 79% in 2018, fostering a culture of preparedness.
Despite these efforts, challenges persist. Foreign residents and tourists, who may lack access to Japanese-language alerts or disaster knowledge, are at higher risk. The government’s 2014 plan to mitigate Nankai Trough damages has fallen short, achieving only a 20% reduction in projected deaths. Coastal residents’ increased awareness of tsunami evacuation protocols is a positive step, but the sheer scale of a magnitude-9 quake could overwhelm even Japan’s robust systems.
Global Impacts: Countries at Risk
A Nankai Trough megaquake would have far-reaching consequences beyond Japan, particularly due to tsunamis and economic ripple effects. While Japan would bear the brunt, neighboring countries and global markets could be affected:
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Tsunami Impacts: Tsunamis up to 34 meters high could strike Japan’s Pacific coast within minutes, potentially reaching Hong Kong, Taiwan, the Philippines, and South Korea. The 2011 Tohoku tsunami affected coasts as far as Chile and California, suggesting that a Nankai Trough event could send waves across the Pacific. Low-lying areas in the Philippines and Indonesia are particularly vulnerable.
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Economic Fallout: Japan, the world’s fourth-largest economy, is a hub for technology and manufacturing. A $1.81 trillion loss could disrupt global supply chains, particularly in semiconductors and automotive industries. Countries like the United States, China, and South Korea, heavily reliant on Japanese exports, would face shortages.
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Tourism and Aviation: The manga-driven panic has already reduced bookings from Hong Kong, Taiwan, and South Korea by up to 50% in 2025, with airlines like Greater Bay Airlines cutting flights. A megaquake would further deter tourism, impacting Japan’s economy and regional travel markets.
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Regional Seismic Triggers: The 2025 Myanmar magnitude-7.7 quake caused a building collapse in Bangkok, 1,000 kilometers away, due to long-period ground motion. A Nankai Trough quake could similarly affect high-rise structures in South Korea, Taiwan, or China.
The Manga Prophecy: Ryo Tatsuki’s “The Future I Saw”
Adding a cultural twist to Japan’s seismic anxiety is Ryo Tatsuki’s manga, Watashi ga Mita Mirai (The Future I Saw), first published in 1999. Tatsuki, often dubbed the “Japanese Baba Vanga,” gained fame after her manga’s cover referenced a “major disaster in March 2011,” coinciding with the Tohoku earthquake and tsunami. The 2021 edition predicts a catastrophic event on July 5, 2025, involving a seabed eruption between Japan and the Philippines, triggering a tsunami “three times taller” than 2011’s. This prophecy, amplified by social media, has fueled panic, with over 1,400 videos garnering 100 million views, particularly in Hong Kong, China, and Taiwan.
Tatsuki’s predictions, based on her dream journal, have been linked to other events, including the 1995 Kobe earthquake and the deaths of Freddie Mercury and Princess Diana. However, she has urged readers not to take her work literally, emphasizing disaster preparedness over panic. “It’s important not to be unnecessarily influenced,” she told the Mainichi Shimbun, advocating for reliance on expert advice. Despite her disclaimer, the manga’s influence has led to a 30% drop in flight bookings and economic losses estimated at ¥560 billion ($3.9 billion) if tourism declines persist.
Scientists, including University of Tokyo’s Naoya Sekiya, dismiss Tatsuki’s predictions as unscientific, noting that precise earthquake forecasting remains impossible. The JMA has reiterated that “any such predictions should be considered unreliable,” yet the manga’s eerie 2011 coincidence and the government’s own megaquake warnings have blurred the line between fiction and reality, amplifying public fear.
Japan’s Leadership Response: The Prime Minister’s Address
In response to growing anxiety, particularly following the August 2024 megaquake advisory and the manga-driven panic, Japan’s leadership has taken proactive steps. Former Prime Minister Fumio Kishida canceled an overseas trip in August 2024 to focus on domestic preparedness after the Miyazaki quake. Current efforts, as of July 2025, include:
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Public Communication: The JMA and government officials have used social media and press conferences to counter misinformation. Ryoichi Nomura, head of the JMA, stated, “It is scientifically impossible to predict earthquakes by specifying the date, location, or magnitude.” The government has urged citizens to rely on verified information and prepare emergency kits.
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Updated Disaster Plans: The Central Disaster Prevention Council revised its Nankai Trough strategy in June 2025, designating 764 municipalities across 30 prefectures as high-risk zones. The plan emphasizes swift evacuation, structural reinforcements, and expanded tsunami flood risk zones.
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Public Preparedness Campaigns: Prime Minister Kishida and successors have addressed the nation, emphasizing practical steps: securing furniture, stockpiling supplies, and confirming evacuation routes. Coastal residents are urged to “run to higher ground” immediately after a quake. Foreigners are a focus, with multilingual alerts and guides to address their vulnerability.
Miyagi Prefecture Governor Yoshihiro Murai has called the manga-driven rumors a “serious issue” for tourism, while Tokushima’s Masazumi Gotoda stressed that earthquakes can occur anytime, urging calm and preparedness. These messages aim to balance urgency with reassurance, ensuring Japan remains a viable destination despite the looming threat.
Potential Damages: A Staggering Toll
The government’s March 2025 report paints a grim picture of a Nankai Trough megaquake’s impact:
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Human Cost: Up to 298,000 deaths, with 215,000 from tsunamis and 52,000 from post-disaster health deterioration. This is 13 times higher than the 2011 quake’s indirect deaths.
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Infrastructure: 2.35 million buildings could collapse, with severe damage in Shizuoka, Wakayama, Kochi, and Miyazaki prefectures. Tsunamis could flood 1,151.5 square kilometers across 30 prefectures.
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Economic Impact: ¥270.3 trillion ($1.81 trillion) in damages, disrupting Japan’s industrial heartland and global supply chains. Long-period ground motion could affect skyscrapers region-wide.
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Social Disruption: 1.23 million evacuees would strain resources, with foreigners at higher risk due to language barriers and limited access to aid.
These estimates assume a worst-case scenario, with a nighttime winter quake maximizing casualties. Mitigation efforts, like retrofitting buildings and expanding evacuation drills, have reduced projected deaths by 20% since 2014, but the scale remains catastrophic.
Balancing Science and Cultural Narratives
The interplay between Tatsuki’s manga and scientific warnings highlights a unique challenge: how to address cultural anxieties while promoting rational preparedness. Japan’s advanced infrastructure and disaster culture make it a global model, yet the manga’s influence reveals a public susceptible to fear-driven narratives. This duality suggests a need for:
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Cultural Sensitivity in Communication: Leveraging manga and media to promote preparedness, as Tatsuki herself advocates, could turn fear into action.
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Global Collaboration: Sharing Japan’s early-warning technology and tsunami defense strategies with vulnerable neighbors like the Philippines could mitigate regional impacts.
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Economic Resilience: Diversifying Japan’s industrial base and tourism campaigns can cushion the economic blow of a megaquake or rumor-driven downturns.
Megaquake is a testament
Japan’s readiness for a Nankai Trough megaquake is a testament to its resilience, with cutting-edge technology and a culture of preparedness. However, the potential for 298,000 deaths, $1.81 trillion in damages, and regional impacts underscores the need for continued investment in infrastructure, public education, and international cooperation. The manga prophecy by Ryo Tatsuki, while scientifically baseless, has amplified awareness, albeit with economic costs. As Japan’s leadership counters misinformation and refines disaster plans, the nation stands as both a warning and a model for living with seismic risk. The question isn’t just whether Japan is ready—it’s whether the world can learn from its example before the next big one strikes.
