Tsunami Travel Time Maps for the Atlantic, Indian and Pacific Oceans

• The maps displayed below were generated using Tsunami Travel Times (TTT) software developed by Paul Wessel , Geoware. (Click on the maps to display larger images of the maps.) The TTT software calculates first-arrival travel times on a grid for a tsunami generated at a given earthquake epicenter.
• The contours on the maps are in 1 hour time intervals. The contours are colored according to the scheme: red contours are for 1-4 hour arrival times, yellow (5-6 hour arrival times), green (7-14 hour arrival times), and blue (15 to 21 hour arrival times).
• Travel time maps are provided for the Atlantic Ocean, Indian Ocean, Pacific Ocean, and for Simulated Travel Time Maps for hypothetical earthquakes in the Indian and Pacific Oceans.
• NOTE: The contours do not provide information on the height or the strength of the wave, only the arrival times.

The earthquakes listed below generated tsunami waves that were observed throughout the Pacific Basin. The travel times maps displayed with each event were generated using the TTT software with earthquake epicenters listed in the NGDC Tsunami Event Database and bathymetry from the NGDC 2-Minute Gridded Global Relief Data.

Click on the "results of a search" link next to each map for more information on the tsunami source event. The tsunami event display has an additional link to the associated runups (locations that observed the wave). In some cases, the runup entries have observed tsunami arrival times. These times can be compared with the calculated arrival times on the maps. The calculated times are usually within 1 hour of the observed travel times, but the times can differ by more than 1 hour, particularly when the location is across the Pacific Basin. See the discussion at the bottom of this page for more information on why the times may be different.

November 1, 1755 Lisbon, Portugal

A large earthquake, Modified Mercalli Intensity XI, in Lisbon, Portgual, caused damage to north of Granada, Spain. The earthquake generated a tsunami that affected the coasts of Portugal, Spain, North Africa, and the Caribbean. The tsunami reached Lisbon about 20 minutes after the first destructive shock. It rose to about 6 meters at many points along the Portguese coast and reached 12 meters in some places. It also affected the coast of Morocco where the streets of Safi were flooded. The tsunami reached Antigua about 9.3 hours after the earthquake. Later waves, with estimated runup heights of 7 meters, were observed at Saba, Netherlands, Antilles. The earthquake and tsunami killed between 60,000 and 100,000 people.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

October 11, 1918 Puerto Rico

A magnitude 7.3 Mw earthquake on October 11, 1918, in the Mona Passage, west of Puerto Rico, was caused by displacement along four segments of a normal fault, oriented N-S in the Mona Canyon. The earthquake generated a tsunami with runup heights reaching 6 meters, causing extensive damage along the western and northern coasts of Puerto Rico. The earthquake and tsunami caused $29 million damage, 116 people were killed and 100 were reported missing.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

November 18, 1929 Grand Banks

On November 18, 1929 a magnitude 7.4 Mw earthquake occurred 250 km south of Newfoundland along the southern edge of the Grand Banks, Canada. The earthquake was felt as far away as New York and Montreal. It triggered a large submarine slump which ruptured 12 transatlantic cables in multiple places and generated a tsunami. The tsunami was recorded along the east coast of Canada and the U.S., as far south as Martinique in the Caribbean, and across the Atlantic Ocean in Portugal. The tsunami caused an estimated $1 million damage and 28 deaths in Newfoundland, Canada.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

August 27, 1883 Krakatau

The explosion of the Krakatau Volcano in Indonesia on August 27, 1883, generated a 30 meter tsunami in the Sunda Strait which killed about 36,000 people. It also caused an atmospheric pressure wave that was recorded on the tide gauges at remote locations including South Georgia Island, Panama, France, England, Alaska, Hawaii, and San Francisco. Due to the shadowing by continents and island groups, a direct tsunami could not have reched most of these locations. Atmospheric gravity waves occurred which may have excited water waves by transferring energy into the ocean. It was recorded with an amplitude of six inches at Sausalito, California. .

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

December 26, 2004 Sumatra, Indonesia

A magnitude 9.4 Mw earthquake occurred off the west coast of Sumatra, Indonesia, on December 26, 2004. It was the fourth largest earthquake in the world since 1900 and the largest since the 1964 Prince William Sound, Alaska, earthquake. The earthquake generated a tsunami that caused more casualties than any other in recorded history. The tsunami was recorded nearly world-wide on tide gauges in the Indian, Pacific and Atlantic Oceans. In total, more than 283,1000 people were killed, 14,1000 are still listed as missing and 1,126,900 were displaced by the earthquake and subsequent tsunami in 10 countries in South Asia and East Africa.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

February 3, 1923 Kamchatka, Russia

The February 3, 1923 magnitude 8.3 Mw earthquake off the east coast of Kamchatka, Russia, generated an 8-meter tsunami that caused damage in Kamchatka and in Hawaii. It was also observed in Japan and California.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

December 7, 1944 Kii Peninsula, Japan

The 1944 Pacific-wide tsunami was caused by a magnitude 8.1 Mw earthquake that occurred off the southeast coast of Kii Peninsula, Japan. The earthquake and resulting tsunami caused great destruction and loss of life. About 998 people were killed, 2135 people were seriously injured, 26,135 homes were totally destroyed, 46,950 homes were partially destroyed, and 3,059 homes were washed away. The tsunami was observed on tide gauges in the Hawaiian and Aleutian Islands.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

April 1, 1946 Unimak Island, Alaska

The April 1, 1946 Pacific-wide tsunami was caused by a magnitude 7.3 Ms earthquake that occurred south of Unimak Island, Alaska. Hawaii experienced the worst damage, with 159 deaths (96 at Hilo) and $26 million in property loss. Total property damage in Alaska was $250,000 while California experienced one death and $10,000 damage from the tsunami. These events led to the development of tsunami travel time charts for the Pacific and the Pacific Tsunami Warning Service.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

December 20, 1946 Honshu, Japan

A catastrophic magnitude 8.1 Mw earthquake on December 20, 1946 on the south coast of Honshu, Japan was felt almost everywhere in the central and western parts of the country. The number of homes destroyed directly by the earthquake was 2,598; 1,443 people died. In addition, 1,451 homes were washed away by the ensuing tsunami waves. The tsunami was observed on tide gauges in California, Hawaii and Peru. (Reference #414)

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

March 4, 1952 Hokkaido, Japan

The magnitude 8.1 Mw earthquake and tsunami on March 4, 1952 off the coast of Hokkaido, Japan, did major damage in Japan. 815 homes were completely destroyed, 1,324 were partially destroyed, 6,395 were slightly damaged, 14 were burned, 91 were washed away, 328 homes and 1,621 non-residential buildings were flooded. Many ships were destroyed, and roads and railway lines were damaged. Twenty-eight people died, 5 people were missing and 287 people were injured in Japan. The tsunami was observed on tide gauges in Hawaii, the west coast of the United States, Alaska, Peru, the Marshall Islands, and Palau.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

November 4, 1952 Kamchatka, Russia

The magnitude 9.0 Mw earthquake on November 4, 1952 off the east coast of Kamchatka generated a 13-meter wave locally. The waves struck the Hawaiian Islands at 1:00 pm. Property damage from these waves in the Hawaiian Islands was estimated at $800,000 to $1,000,000; however no lives were lost. It also caused damage on the west coast of the United States and was observed on tide gauges throughout the Pacific Basin.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

March 9, 1957 Aleutian Islands, Alaska

The magnitude 9.1 Mw earthquake on March 9, 1957 south of the Andreanof Islands, Aleutian Islands, generated a tsunami that did severe damage on Adak Island. However, the most damage (about $5 million) was done in the Hawaiian Islands. There were two indirect fatalities, a reporter and a pilot, and injury to a photographer when their small chartered plane crashed in the ocean near Oahu.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

May 22, 1960 Southern Chile

On May 22, 1960 a Magnitude 9.5 Mw earthquake, the largest earthquake ever instrumentally recorded, occurred in southern Chile. The series of earthquakes that followed ravaged southern Chile and ruptured over a period of days a 1,000 km section of the fault. The number of fatalities associated with both the earthquake and tsunami has been estimated to be between 490 and 5,700. Reportedly there were 3,000 injured and intitially there were 717 missing in Chile. The main shock generated a tsunami that was not only destructive along the coast of Chile, but also caused numerous casualties and property damage in Hawaii and Japan, and was noticeable along shorelines throughout the Pacific Ocean area.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

March 28, 1964 Prince William Sound, Alaska

This magnitude 9.2 Mw earthquake and ensuing tsunami caused 125 deaths and $311 million in property loss ($84 million and 106 deaths in Alaska). It was felt over a large area of Alaska and in parts of western Yukon Territory and British Columbia, its effects were heaviest in south central Alaska. The duration of the shock was estimated at 3 minutes. Vertical displacement occurred over 525,000 sq km. About 20 landslide tsunamis were generated; the tectonic tsunami devastated many towns along the Gulf of Alaska, left serious damage in British Columbia, Hawaii, and along the west coast of the U.S. (15 killed), and was recorded on tide gages in Cuba and Puerto Rico.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

May 16, 1968 Honshu, Japan

A magnitude 8.2 Mw earthquake on May 16, 1968 off the coast of Honshu Island caused destruction in Japan and generated a tsunami that was observed by tide gauges in Japan and throughout the Pacific Basin. As a result of the earthquake and tsunami, 52 people died and 329 people were injured; 676 homes were completely destroyed and 2,994 homes were partially destroyed; 13 homes burned down and 529 homes were flooded; 97 ships were washed away and 30 were sunk. In addition, roads, bridges and protective dikes were destroyed.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

November 29, 1975 Hawaii

On November 29, 1975 a magnitude 7.2 Ms earthquake on the southern coast of the Island of Hawaii generated a locally damaging submarine landslide tsunami that was recorded at tide gauge stations in Alaska, California, Hawaii, Japan, Galapagos Islands, Peru, and Chile. The tsunami caused $1.5 million damage in Hawaii, 2 deaths, and 19 injuries.

For more information on this event link to the search results of the NGDC Tsunami Event Database for this event.

One-hour Tsunami Travel Times for Simulated Seismic Zones in the Indian Ocean

These maps were generated by the Pacific Warning Center using Paul Wessel's TTT software. The first image shows one-hour travel times from simulated seismic zones off the Makran and Sumatra-Andaman coasts, Indian Ocean. A 100-kilometer distance around the seismic zones is also shown on the map as a dashed line. The other two images show zoomed in images of the two areas.

Off the coast of central Chile

Travel time map for a hypothetical magnitude 9.2 earthquake off the coast of central Chile at 30^oS, 72^oW. This scenario will be used for the Pacific-wide Tsunami Drill Exercise Pacific Wave '06 to take place 16-17 May 2006. Visit the Intergovernmental Coordination Group for the Pacific Tsunami Warning and Mitigation (ICT/PTWS) for more information.

North of the Philippines

Travel time map for a hypothetical magnitude 8.8 earthquake north of the Philippines at 20^oN, 120^oE. This scenario will be used for the Pacific-wide Tsunami Drill Exercise Pacific Wave '06 to take place 16-17 May 2006. Visit the Intergovernmental Coordination Group for the Pacific Tsunami Warning and Mitigation (ICT/PTWS) for more information.

Tsunami Travel Time Software

The technique used by the software to compute travel times over an entire grid is an application of Huygen's principle. It states that all points on a wavefront are point sources for secondary spherical waves. Minimum travel times are computed over the grid starting at the point of interest (e.g. earthquake epicenter). From the starting point, times are computed to all surrounding points. The grid point with minimum time is then taken as the next starting point and times are computed from there to all surrounding points. The starting point is continually moved to the point with minimum total travel time until all grid points have been evaluated. This technique is explained in Shokin, Y.I., L.B. Chuborav, V.A. Novikov, and A.N. Sudakov, "Calculations of tsunami travel time charts in the Pacific Ocean - models algorithms, techniques, results, Science of Tsunami Hazards, Vol. 5, p. 85-113.

Tsunamis are categorized as long waves, therefore, tsunami travel times can be computed with water depth as the only variable (Murty, T.S., Seismic Sea Waves Tsunamis, Bulletin 198, Department of Fisheries and the Environment, Fisheries, and Marine Service, Ottawa, 336 p.) Long waves are those in which the distance between crests of the wave is much greater than the water depth through which the wave is traveling. Wave speed is computed from the square root of the quantity water depth times the acceleration of gravity. So, tsunami travel times can be computed without any knowledge of the tsunami's height, wavelength, etc.

There are several situations in which the predicted estimated times of arrival may not match observed arrival times of the tsunami waves, including but not limited to the following:

1. The bathymetry is not accurate in the vicinity of the epicenter.
2. The epicenter is not well located, or its origin time is uncertain.
3. The epicenter is on land and a pseudo-epicenter off the coast must be selected.
4. The bathymetry is not accurate in the vicinity of the reporting station.
5. Nonlinear propagation effects may be important in shallow water.
6. The observed travel times do not represent the first wave but instead are later arrivals.