Tsunamis - a brief history

Drop a stone into a small pond and it will create a series of ripples. A tsunami is just like those ripples, but rather than a stone, the disturbance which sets it in motion is often an undersea earthquake, landslide or volcanic eruption. The seafloor buckles where drifting plates collide and waves emanate, hitting the shore hard with almost all of its initial energy.

Tsu (harbour) nami (wave). The term is said to have originated with Japanese fishermen who, upon returning to port, found the area surrounding the harbour devastated. History demonstrates the Pacific Ring of Fire’s vulnerability to tsunamis, but also shows its impact elsewhere:

2004 Indian Ocean Tsunamis Affecting Southern Asia and Eastern Africa

A massive earthquake measuring over 9.0 on the Richter scale occurred under the Indian ocean floor just off the coast of the Indonesian island of Sumatra. Tsunami waves slammed into the coastline of 12 Indian Ocean countries (Indonesia, India, Sri Lanka, Thailand, Malaysia, Maldives, Myanmar, Bangladesh, the Andaman and Nicobar Islands, the Maldives, Seychelles, Somalia, Tanzania, and Kenya) and killed over 230,000 people. The earthquake that generated the great Indian Ocean tsunami of 2004 is estimated to have released the energy of 23,000 Hiroshima-type atomic bombs, according to the U.S. Geological Survey (USGS).

1998 Tsunami Affecting Papua New Guinea

On July 17th, 1998, an earthquake measuring 7.1 on the Richter scale occurred about 15 miles just off the coast of northern Papua New Guinea, an island nation located in the southwestern Pacific Ocean just south of Indonesia and north of Australia. While the magnitude of the quake was not large enough to create the tsunami directly, it is believed the earthquake generated an undersea landslide, which in turn caused the tsunami. Following the earthquake, a tsunami with waves reaching 12 meters (40 feet) hit the Papua New Guinea coast within 10 minutes, destroying the villages of Arop and Warapu. An estimated 2,200 people were killed.

1976 Tsunami Affecting the Philippines

August 1976 and an earthquake measuring approximately 7.6 on the Richter scale occurred in the Moro Gulf a few miles away from the coast of the Philippine island of Mindanao. The earthquake itself was responsible for causing widespread damage, but its effect paled in comparison to the tsunami it helped created. The massive tsunami that devastated 700 kilometers of coastline destroyed coastal towns and killed over 5,000 people.

1964 Tsunami Affecting the West Coast of North America

The Good Friday Tsunami was caused by an earthquake (9.2) off the coast of Alaska. Waves reached heights of 11.5 meters and killed 106 people.

1960 Tsunami Affecting Chile and Pacific Nations

On May 22 1960, the biggest earthquake ever recorded at the time occurred just off the coast of South central Chile, a nation of South America. The earthquake measured 9.5 on the Richter scale with swarms of aftershock earthquakes that measured as large 8.0 that followed. The earthquakes triggered the creation of tsunami, which was responsible for most of the ensuing devastation and death of 2,000 people. The waves spread outwards across the Pacific, flooding Hilo (on the island of Hawaii), causing 200 deaths in Japan and damage in the Marquesas, in Samoa, and in New Zealand.