What do we know about tsunami throughout history?

Throughout history, destructive tsunami have occurred in all of the world's oceans and seas. Although tsunami occur most frequently in the Pacific Ocean, they are also known to occur anywhere and many ancient descriptions of sudden catastrophic waves exist.

This map shows the location, size and intensity of over 2,000 tsunami events that have occurred since 1628BC. The colour of the circle reflects the tsunami intensity and the bigger the circle, the greater the event. Most tsunami have been generated along the active tectonic plate boundaries.

Some major historical events

1755 Lisbon

The Lisbon undersea earthquake and tsunami occurred on 1 November 1755 at 9:40am. The tsunami, and subsequent fire, engulfed the city killing between 60,000 to 100,000 people. This was one of the most destructive events in recorded history. Geologists today estimate that the Lisbon earthquake was a magnitude 9 event.

1883 Krakatoa

The Krakatoa eruption of 27 August 1833, was amongst the most severe volcanic explosions in modern times. This catastrophic volcanic eruption caused two-thirds of the island to collapse beneath the sea. This generated a series of devastating tsunami, some as high as 35 metres. Tsunami ravaged nearby coastlines of Java and Sumatra, killing close to 40,000 people. Vessels as far away as the South African coastline were affected by this event.

This map of Krakatoa shows the area of land mass that collapsed into the ocean as a result of this event.

1896 Japan

On 15 June 1896 at approximately 7:30pm, a magnitude 8.5 earthquake off the Sanriku Coast, Japan, triggered a tsunami which arrived on shore 30 minutes later. Although the earthquake itself is not thought to have resulted in any fatalities, the tsunami which reached a height of 38.2 metres in places killed almost 20,000 people.

1946 Hilo

Another destructive Pacific-wide tsunami was generated by a magnitude 7.8 earthquake near Unimak Island, Alaska. Five hours after the initial earthquake, and without warning, a tsunami reached Hawaii causing considerable damage and loss of life. The tsunami completely obliterated Hilo's waterfront, killing 159 people.

This image shows the 1946 tsunami breaking over palm trees at Hilo.

1958 Lituya Bay

Lituya Bay, Alaska, was the site of the largest localised tsunami ever recorded. On the evening of 7 July 1958 a magnitude 8.0 earthquake caused a massive rockslide at the head of Lituya Bay. The land mass fell into the bay causing the water to surge and generate a tsunami. It inundated approximately 13 square kilometres of land along the shores of Lituya Bay, sending water as far as 1,000 metres inland and clearing millions of trees. The tsunami reached a height of 524 metres.

This image shows bare rock where trees were cleared by the 1958 tsunami.

1964 Alaska

On 29 March 1964 Prince William Sound, Alaska, was hit by a magnitude 9.2 earthquake. The earthquake generated a major tsunami that struck the southeast coast of Alaska, the pacific coast of British Columbia and the west coast of the United States. The violent shaking during the earthquake caused many large landslides and undersea landslides, which also produced destructive localised tsunami at many locations along the Alaskan coast.

This image shows the extent of inundation along the coastline of Valdese, Alaska, in 1964.

1998 Papua New Guinea

A tsunami struck the north coast of Papua New Guinea on Friday 17 July 1998. The tsunami was thought to have been caused by an undersea landslide which resulted from a magnitude 7 earthquake and which produced movement of the sea bed. The tsunami caused widespread injury, resulting in the deaths of over 2,000 people and leaving approximately 9,500 people homeless. Tsunami wave heights reached 15 metres in some areas.

This image shows an example of the damage caused by the 1998 Papua New Guinea Tsunami.

2004 Indian Ocean

On the morning of 26 December 2004 a magnitude 9.3 undersea earthquake occurred off the west coast of Sumatra, where the Indo-Australian Plate is sliding under the Eurasian Plate. The part of the fault that ruptured was 1200 kilometres long and caused part of Indonesia to move westwards by five to ten metres. This displacement of the ocean floor caused a tsunami, devastating communities in Indonesia, Sri Lanka and Thailand and affecting many other countries along the Indian Ocean rim. Close to 300,000 people lost their lives.

This image shows the 2004 Indian Ocean Tsunami approaching Koh Jum Island in Thailand.