20 Tsunami Facts

1. 95% of tsunamis are caused by earthquakes of magnitudes greater than 7 and depths less than 30 km. The majority of these tsunamigenic earthquakes occur in subductions zones where a large vertical movement occurs on the fault. 
2. Tsunamis generated by earthquakes have caused the largest fatalities and greatest damage. They also propagate the furthest from source.
3. 81% of tsunamis are generated by earthquakes, 6% by volcanoes, 3% by landslides and 10% from unknown sources.
4. Based on 13,000 runup locations of where tsunami effects were observed; 82% have occurred in the Pacific Ocean, 9% in the Indian Ocean, 4% in the Mediterranean Sea, 3% in the Atlantic Ocean and 2% in the Caribbean Sea.
5. 21% of volcano fatalities have been a result of volcanogenic tsunamis.
6. Between 1900 to present, over 700 fatalities have occurred from Tsunamis in the Pacific Ocean.
7. 2000 B.C was the first recorded tsunami which occurred on the coast of Syria. Tsunamis have been well documented especially in Japan and the Mediterranean areas.
8. 42 deadly tsunamis have occurred since 1975. 70% of these occurred in the Pacific Ocean.
9. Between 1610 BC to AD 2016, 1235 confirmed tsunamis have occurred of which 249 were deadly. 76% of these occurred in the Pacific Ocean and 87% were caused by earthquakes.
10. Tsunamis have caused over 500,000 fatalities over the world. The Indian Ocean tsunami in 2004 is responsible for 227,898 of these fatalities.
11. Between 1900 to 1990 an estimated 33,500 fatalities have occurred from tsunamis. Between 1990 to 2004, over 230,00 fatalities have occurred due to tsunamis.
12. The September 2009 American Samoa tsunami, February 2010 Chile tsunami and October 2010 Indonesia tsunami in combination have caused over 400 fatalities.
13. The highest recorded tsunami was nearly 525 metres high (1720 feet). It was caused by an earthquake in Lituya Bay, south east of Alaska in 1958. Two fatalities resulted from this tsunami.
14. In the Mediterranean Sea, 84% of tsunamis have been caused by earthquakes and 4% by volcano eruptions.
15. According to EM-DAT, between 1900 to 2009, 240,959 fatalities have occurred as a result of tsunamis. 2.48 million others have been affected. This is an underestimate as the Indian Ocean tsunami itself affected millions.
16. An average of one damaging tsunami event per year takes place.
17. 95% of the most damaging take place in the Pacific Ocean.
18. On average tsunamis cause 300 deaths per year.
19. Millions of coastal population are at risk from tsunamis. 1.2 million are on the western coast of U.S alone.
20. Tsunamis are a significant hazard in the Caribbean Sea where 77 tsunami events have been recorded. An example is the magnitude 8.1 earthquake which generated a tsunami in 1946 killing 1800 people.