World Tsunami Awareness Day: Understanding, Preparing, Innovating

World Tsunami Awareness Day, observed every November 5th, is a global reminder of the immense power and devastation tsunamis can unleash and the importance of preparedness in coastal and maritime communities.  

With rapid urbanization along shorelines and volatile climate patterns, the risks posed by these rare but catastrophic events are mounting, making actionable knowledge more crucial than ever. 

What is World Tsunami Awareness Day?

World Tsunami Awareness Day originated in Japan, informed by centuries of innovation and tragedy in tsunami risk management. Established by the United Nations in 2015, the day’s purpose is to educate, foster international cooperation, and encourage sharing of technological approaches to risk reduction, such as early warning systems and evacuation strategies. 

Recommended reading from Martide*: World Maritime Day* 

The Science Behind Tsunamis: Definition and Causes 

A tsunami is a series of waves in a water body, typically the ocean, triggered by the displacement of a large volume of water. Unlike wind waves, tsunamis can travel at jetliner speeds, up to 800km/h, across ocean basins, growing in height as they approach shore. 

The main causes: 

• Underwater Earthquakes: The most common source, especially at tectonic plate boundaries. 

• Volcanic Eruptions: Particularly explosive or submarine eruptions, such as Tonga in 2022, can generate tsunamis. 

• Submarine and Subaerial Landslides: Rapidly moving material underwater or sliding into the ocean displaces water. 

• Impact Events: Asteroid or meteorite strikes are rare but can cause massive ocean displacement. 

• Underwater Explosions: Both natural (volcanic) and artificial events may trigger regional tsunamis. 

• Meteotsunamis: Atmospheric disturbances can cause local tsunami-like waves. 

• Wind Waves: While fundamentally different, these are often confused in public discourse. 

Who Is At Risk From Tsunamis? 

Coastal areas and islands are, naturally, most at risk from tsunamis, however their impact can be felt surprisingly far inland too. 

Homes, businesses, communities, infrastructure, schools, places of worship, industries, the local economy and the local ecosystem can all be left destroyed or severely damaged in the wake of a tsunami. 

As per the United Nations: 

“By the year 2030, an estimated 50 per cent of the world’s population will live in coastal areas exposed to flooding, storms and tsunamis. Scaling up international cooperation to developing countries will help ensure that 100% of communities at risk of tsunami are prepared for and resilient to tsunamis by 2030.” 

Just look at that statistic again: Half of the people living on earth in just eight short years are at increasing risk of destruction and loss of life due to our increasingly volatile weather systems. 

Recent Tsunami Events and Lessons Learned 

2024 marked the 20th anniversary of the Indian Ocean Boxing Day tsunami, the deadliest tsunami in modern history, with over 230,000 lives lost across 14 countries. This year, a major 8.8 magnitude earthquake off Kamchatka, Russia again demonstrated how far the science and technology of tsunami preparedness has advanced. Millions were evacuated across the Pacific using sophisticated early warning systems, resulting in minimal casualties compared to historic disasters. 

Innovations include: 

• Deep-sea pressure sensors (“tsunameters”) relaying live ocean data to satellites for instant modeling and warnings. 

• Real-time global coordination, with bodies like the Pacific Tsunami Warning Center leading rapid alerts. 

• Artificial intelligence applications now support improved prediction for non-earthquake-generated tsunamis, including those caused by landslides and volcanic eruptions. 

Tsunami Statistics: Facts That Matter

• In the past 100 years, over 260,000 people have been killed by 58 recorded tsunamis, making them deadlier on average than any other natural disaster. 
• Between 1998 and 2018, tsunamis caused an estimated $200 billion in economic losses. 

• Tsunami wavelengths can exceed 200 km in deep ocean and travel at speeds of over 800 km/h. 

• Maximum runup (wave splash mark) in recent Kamchatka event reached 17-19 meters in some locations, underscoring ongoing risk even with sophisticated warnings. 

• Volcanic tsunamis are responsible for more than 20% of all volcanic-related deaths in the last 250 years.  

What was the impact of the Indian Ocean tsunami? 

The horrors of the Indian Ocean tsunami, which hit on December 26th, as many across the globe were celebrating the Christmas holiday spurred the international community into action. 

Just three weeks after the disaster, a meeting was held in Kobe, Japan in which governments across the globe agreed to adopt what would be the first comprehensive global agreement on disaster risk reduction, the 10-year Hyogo Framework for Action. 

This came to an end in 2015, ten years after its implementation and was succeeded by the 15-year Sendai Framework which will be in existence until 2030. 

One of the main objectives of this particular framework is to push risk reduction to the fore to reduce the loss of life in coastal regions which are becoming increasingly populated due to the growth of tourism and urbanization. 

In addition to this, the Indian Ocean Tsunami Warning and Mitigation System was also created. The system comprises a multitude of seismographic and sea-level monitoring stations which circulate warnings to national tsunami information centers. 

What Maritime Professionals Need to Know 

Unlike general disaster preparedness, the maritime industry faces unique challenges and responsibilities: 

• Seafarers can be the first to witness tsunami formation, and accurate onboard procedures save lives. 

• Innovative software and technology can help coordinate rapid response and evacuation, manage crew locations worldwide, and meet compliance for tsunami risk zones. 

Risk Reduction and Community Preparedness

Tsunamis cannot be prevented, but their impacts can be dramatically reduced with education and planning. Key measures: 

• Maintain updated evacuation routes and signage. 

• Engage communities with regular drills and awareness activities, especially on World Tsunami Awareness Day. 

• Use #WorldTsunamiAwarenessDay to amplify community stories and best practices. 

• Governments should work with international bodies to share lessons and fund resilient infrastructure. 

Further reading*: World Drowning Prevention Day * 

Frequently Asked Questions 

What is a tsunami? 

A tsunami is a series of massive waves caused by the displacement of water, typically following earthquakes or volcanic eruptions near or under oceans. 

Can tsunamis be predicted? 

Earthquake-generated tsunamis can be detected rapidly by seismic and deep-ocean sensors, but predicting exact timing remains a scientific challenge. 

What are the warning signs? 

A strong or long earthquake near the coast (“Long or strong, get gone”), unusual rapid ocean retreat, or official warning sirens and alerts are the main warning signs. 

How far inland can a tsunami reach? 

Depending on terrain and wave height, tsunamis can inundate areas many kilometers inland. 

What is the world’s deadliest tsunami? 

The 2004 Indian Ocean tsunami is the deadliest recorded, with an estimated death toll of over 230,000. 

Are earthquakes only dangerous for tsunamis? 

No. Volcanic eruptions, landslides, meteorite impacts, underwater explosions, and meteotsunamis can also generate dangerous waves. 

Does every earthquake at sea cause a tsunami? 

No. Only quakes that involve significant vertical movement of the sea floor, usually above a certain magnitude (6.5+), can trigger a tsunami. 

How to observe World Tsunami Awareness Day 

World Tsunami Awareness Day is about getting international communities, organizations and governments to work together to lessen the impact of tsunamis across the globe. 

Tsunamis can’t be prevented but their catastrophic impact can be reduced if coastline communities understand the risks of living in a tsunami-prone region, and know how to react. 

For example: The authorities must warn the local population as far in advance as possible when a tsunami is forecast, and they must ensure that people know how to respond - for example by getting as far inland or to the highest ground possible. 

If you live in a region that is at risk from tsunamis, you may find that there are events being held to help educate and prepare the community, and you can also use the hashtag #WorldTsunamiAwarenessDay to spread your own message. 

Source: United Nations World Tsunami Awareness Day 

This blog post was originally published on November 3rd 2022 and updated on September 14th 2025