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Tsunamis in History
Using Tsunami Data to Improve Public Safety
Tsunamis demonstrate nature’s untameable power. They occur in every ocean and reach almost unimaginable heights. They can happen at any time and travel the entire globe in mere hours.
Typically caused by undersea disturbances such as earthquakes, volcanic eruptions, and landslides, tsunamis are a series of waves that are long in length and time and can grow to hundreds of feet high when they reach the coast. Images of tsunamis reaching land show their chilling nature and destructive capacity. They can damage or destroy buildings and infrastructure as well as disrupt transportation, power, communications, and water supply. Waves sometimes travel up to a mile inland, devastating human and natural environments alike.
Tsunamis can also be deadly. According to the NOAA National Centers for Environmental Information (NCEI) , tsunamis took the lives of at least 290,000 people in the past 100 years. These figures could be much higher, but in many events the actual number of fatalities is not known. Their elusive nature contributes to their deadly impact. Unlike many natural hazards, the number of tsunamis is low. Since 1900, fewer than 900 tsunamis have occurred, and only 125 of those were fatal.
Tsunami Source Events (1850 to Present) Time-Lapse Animation. Points indicate how tsunamis were caused: orange circles are earthquakes, red triangles are volcanic eruptions, and green squares are landslides. (Source: NCEI )
The signs of an oncoming destructive tsunami can be distinguished from ordinary sea conditions. Unusual and rapid fluctuations of the sea, such as receding tides, signal a tsunami wave is approaching. Other tsunami natural warning signs include ground shaking and a roaring sound from the sea. These natural warning signs may not always precede a tsunami; thus tsunami detection systems are needed.
NOAA's National Weather Service (NWS) provides tsunami alert services to vulnerable coastal areas in the United States and internationally through the U.S. National Tsunami Warning Center and the Pacific Tsunami Warning Center. NWS alerts and warnings improve public sensitivity to tsunamis and diminish some risk factors. The NWS and the National Tsunami Hazard Mitigation Program, a partnership led by NOAA, have also established the TsunamiReady® program to help communities minimize the dangers posed by tsunamis through better risk assessment, planning, education, and warning communications.
Global map of tsunami event dates and earthquake magnitudes highlighted in this StoryMap. Scroll down to view more information about each event.
Behind this warning system are data. A broad range of scientific data, including from previous tsunamis, is used to develop models for faster and more reliable tsunami forecasts as well as inundation modeling to assist coastal communities in their efforts to assess the risk and mitigate the potential of tsunami hazard. NCEI plays an important role in stewarding this critical data. NCEI houses the Global Historical Tsunami Database and the Deep-ocean Assessment and Reporting of Tsunamis (DART®) Database . These databases contain information for thousands of tsunamis all over the globe.
While potentially devastating and deadly, each tsunami event has provided an opportunity—through the stewardship of data and the application of science—to help coastal residents across the globe become more prepared for tsunamis.
Below are seven tsunami events that had an impact on advancing tsunami science. Each event is accompanied by several maps. To learn how to use the maps, go to "Map Guide" in the navigation bar near the top of this page. It also contains a Map Key Glossary which defines some of the technical terms.
1946 Alaska
Wreckage of business buildings along Kamehameha Avenue in Hilo, Hawaii from the 1946 Alaska tsunami. (Source: Orville T. Magoon; NCEI Natural Hazards Image Database )
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
Four of the largest earthquakes in recorded history occurred between 1946 and 1964.
Each triggered a tsunami that inflicted widespread human casualties, property damage, and destruction.
Each was also instrumental in influencing the development of tsunami warning systems.
On April 1, 1946, a large earthquake with magnitude 8.6 struck Alaska's Aleutian Islands, sending a tsunami across the Pacific basin.
Modeled tsunami amplitudes are displayed using a color scale, where blue is either zero or the smallest, and red is the highest or greater than 3 meters. (Source: NOAA )
Map/Image: “Energy map”, or a modeled, mathematical colored surface representing the maximum rise in sea-level caused by the tsunami (see Deep-Ocean Tsunami Amplitude image above). Contoured lines with numbers indicate the modeled time (in hours) that the waves traveled from the source (red star). (Source: NOAA )
Wave heights reached as much as 17 meters on the Hawaiian Islands, killing 158 people there and ten more in Alaska, California, French Polynesia, and Peru.
Damage to Hilo pier done by tsunami. (Source: University of California at Berkeley; NCEI Natural Hazards Image Database )
Alaskan Damage
The five-story Scotch Cap lighthouse on Unimak Island, Alaska, located 9.8 meters above sea level, was destroyed. Only the foundation and part of the concrete sea wall remained. All five occupants were killed. The waves deposited debris as high as 35 meters above the sea.
The Scotch Cap lighthouse on Unimak Island, Alaska, before (A) and after (B) the April 1, 1946, tsunami. All five occupants were killed. (Source: NCEI Natural Hazards Image Database )
Hawaii
The property damage in Hawaii alone was $26 million (in 1946 dollars).
Building and communications system damage on Kamehameha Avenue. (Source: Orville T. Magoon; NCEI Natural Hazards Image Database )
House pushed over by wave near Moloaa Bay. (Source: Orville T. Magoon; NCEI Natural Hazards Image Database )
Hawaiian Damage
Washout of Oahu Railway and Land Company's railroad near Sunset Beach. (Source: Orville T. Magoon; NCEI Natural Hazards Image Database )
View of tsunami debris floating in Hilo Harbor. (Source: James W. Duncan; NCEI Natural Hazards Image Database )
Background image: Hilo, Hawaii. Aerial view showing extent of inundation in area of Hilo Electric Company resulting from first wave as secondary wave approaches the area. (Source: University of Hawaii; NCEI Natural Hazards Image Database )
Caspar Beach, California
Big logs carried through a narrow bridge by a wave that rose to the bottom of bridge stringer. Water height, 0.05 feet (0.15 meters). (Source: Howard Anderson; NCEI Natural Hazards Image Database )
Half Moon Bay, California
Water height of 14.8 feet (4.5 meters) at Half Moon Bay, California. High water reached windows sills. (Source: Howard Anderson; NCEI Natural Hazards Image Database )
1960 Chile
The Waiakea area of Hilo, Hawaii damaged by the 1960 Chile tsunami. Note the scattered debris, gutted foundation and the parking meters that were bent parallel to the ground by the force of the waves. (Source: U.S. Navy; NCEI Natural Hazards Image Database )
In 1960, the largest earthquake ever instrumentally recorded struck southern Chile.
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
The global extent of this tsunami led to the creation of the Pacific Tsunami Warning and Mitigation System in 1965.
Today, the U.S. Tsunami Warning System includes the National Tsunami Warning Center and Pacific Tsunami Warning Center that forecast wave heights and arrival times of tsunamis as they cross the ocean.
The magnitude 9.5 earthquake generated a tsunami that was not only destructive along the coast of Chile but also caused numerous casualties and extensive property damage as far away as Hawaii, Japan, and the Philippines.
Hilo, Hawaii: Destruction of beach property and extent of inundation. (Source: Herb Hardin; NCEI Natural Hazards Image Database )
Waves were observed throughout the Pacific Ocean basin. Additionally, tide gauges recorded waves in the Atlantic Ocean, as well as the Indian Ocean, making it the first globally recorded tsunami.
Modeled tsunami amplitudes are displayed using a color scale, where blue is either zero or the smallest, and red is the highest, or greater than 3 meters. (Source: NOAA )
Map/Image: “Energy map”, or a modeled, mathematical colored surface representing the maximum rise in sea-level caused by the tsunami (see Deep-Ocean Tsunami Amplitude image above). Contoured lines with numbers indicate the modeled time (in hours) that the waves traveled from the source (red star). (Source: NOAA )
Chile
In the Chilean areas of Maullín, Quenuir, and La Pasada alone, at least 122 people lost their lives in the ensuing tsunami.
The number of deaths in Chile associated with both of the catastrophic earthquake and tsunami events has been estimated between 490 to 5,700.
Submerged land in the Valdivia district. The series of earthquakes that followed ravaged southern Chile and ruptured over a period of days a 1,000 km section of the fault, one of the longest ruptures ever reported. (Source: Pierre St. Amand; NCEI Natural Hazards Image Database )
Japan
The tsunami hit the Pacific coast of Japan almost a day after the earthquake, causing deaths and destroying almost 3,000 houses.
Seen safely from high ground, a wave of the 1960 Chilean tsunami pours into Onagawa, Japan. (Source: NOAA)
Hawaii
In Hawaii , the tsunami caused 61 deaths and 43 injuries, while two deaths took place on the West Coast of the United States.
Hilo, Hawaii: Total destruction of building near Hilo theater. (Source: Pacific Tide Party, NOAA; NCEI Natural Hazards Image Database )
1992 Nicaragua
The tsunami damage at El Transito, (population 1,000), the area most devastated by the tsunami in Nicaragua. (Source: Harry Yeh, University of Washington; NCEI Natural Hazards Image Database )
In the early evening of September 1, 1992, a deadly tsunami struck the Pacific coast of Nicaragua and northern Costa Rica, triggered by a nearby earthquake.
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
The earthquake and tsunami left at least 170 people dead, approximately 500 injured, and more than 13,500 homeless. The tsunami caused most of the damage. Waves reached a maximum of 10 meters (32.8 feet) high, sweeping away houses, boats, vehicles, and anything else in their path.
The total damage was estimated at $20 to $30 million (in 1992 dollars).
In a typical earthquake-tsunami sequence, communities near the source feel the earthquake and, if properly alerted to their hazards, brace for the possibility of a tsunami.
But the 1992 Nicaragua earthquake did not follow this typical pattern.
The damaged structures along the beach at Marsella after the tsunami. Waves at this location reached a height of more than eight meters and scoured the beach, leaving exposed roots. (Source: Harry Yeh, University of Washington; NCEI Natural Hazards Image Database )
Although previously theorized, no one had observed seismograms where a tsunami earthquake had unfolded or developed methods for quickly calculating a reliable magnitude for them. The 1992 earthquake in Nicaragua changed that.
Background image: The shed on the left was toppled by the waves and the structure on the right was damaged by the tsunami at El Popoyo. (Source: Harry Yeh, University of Washington; NCEI Natural Hazards Image Database )
During the 1992 earthquake off of Nicaragua, the fault rupture occurred more slowly than a typical earthquake. Prior to this, there had been no high quality recordings on broadband seismometers of a tsunami earthquake.
The Nicaragua event became the first tsunami earthquake ever recorded by broadband seismometers allowing scientists to make interpretations about the rupture components and the mechanics of tsunami generation.
Structures at El Popoyo, where 15 people lost their lives. Waves at this location reached a height of 5.6 meters. One wall and a foundation are all that remain of a house that was entirely removed by the tsunami. Repairs have begun to the structure on the right. (Source: Harry Yeh, University of Washington; NCEI Natural Hazards Image Database )
The unusual earthquake source characteristics of the tsunami earthquake led to the development of the first International Tsunami Survey Team (ITST).
Scientists and engineers from Japan and the United States, aided by local Nicaraguan scientists and engineers, surveyed the impacted areas within three weeks of the event to document the tsunami’s effects.
Today, post-tsunami surveys regularly examine geologic effects (e.g., deposits and erosion) of tsunamis.
The beach area at El Popoyo after the tsunami. A large rock shown in the photo was carried from an offshore region 50 meters inland and raised 1.85 meters above sea level. The rock measured 2.3 meters by 1.6 meters by 0.5 meters thick and provides a silent testimony of the force of the waves at this location. (Source: Harry Yeh, University of Washington; NCEI Natural Hazards Image Database )
2004 Sumatra, Indonesia
The aftermath of the Dec. 26 tsunami which destroyed Banda Aceh, Sumatra, Indonesia. (Source: Photographer's Mate 3rd Class Tyler J. Clements, U.S. Navy; NCEI Natural Hazards Image Database )
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
On December 26, 2004, a magnitude 9.1 northern Sumatra, Indonesia earthquake generated a tsunami that was observed worldwide, causing tremendous devastation, and taking the lives of over 225,000 people throughout the Indian Ocean region.
The tsunami is currently the most deadly in recorded history.
A giant earthquake ruptured the greatest fault length of any recorded earthquake, spanning a distance of 900 miles (1500 kilometers), longer than the state of California.
Boats were clustered and washed ashore near downtown Banda Aceh, Sumatra. (Source: Michael L. Bak, U.S. Department of Defense; NCEI Natural Hazards Image Database )
Though catastrophic, this event was the catalyst behind the development of the Indian Ocean Tsunami Warning and Mitigation System and ongoing public outreach and education.
Modeled tsunami amplitudes are displayed using a color scale, where blue is either zero or the smallest, and red is the highest, or greater than 3 meters. (Source: NOAA )
Map/Image: “Energy map”, or a modeled, mathematical colored surface representing the maximum rise in sea-level caused by the tsunami (see Deep-Ocean Tsunami Amplitude image above). Contoured lines with numbers indicate the modeled time (in hours) that the waves traveled from the source (red star). (Source: NOAA )
Background image: A village near the coast of Sumatra lays in ruin after the tsunami that struck Southeast Asia. (Source: Photographer's Mate 2nd Class Philip A. McDaniel, U.S. Navy; NCEI Natural Hazards Image Database )
Banda Aceh, Sumatra, Indonesia
Tsunami damage at PT Semen Andalas Cement factory. (Source: Costas Synolakis, University of Southern California; NCEI Natural Hazards Image Database )
India, Sri Lanka, and Maldives
Debris from destroyed homes was washed into the streets and paths making access to remaining or partially damaged homes difficult. (Source: Joseph Trainor, University of Delaware, Disaster Relief Center; NCEI Natural Hazards Image Database )
Background image: View to the south of the Triton Hotel, Sri Lanka at about 10:13 AM local time. The debris is furniture from the dining room of the hotel. (Source: Chris Chapman, Schlumberger Cambridge Research, Cambridge, U.K.; NCEI Natural Hazards Image Database )
View from the top floor of the Triton Hotel, Sri Lanka above the swimming pool at 10:12 AM local time at the highest level, about 5 minutes after the lowest. (Source: Chris Chapman, Schlumberger Cambridge Research, Cambridge, U.K., NCEI Natural Hazards Image Database )
2009 Samoa Islands
Near Pago Pago Park. (Source: NCEI Natural Hazards Image Database)
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
On September 29, 2009, two large earthquakes struck midway between Samoa and American Samoa, a U.S. territory.
The earthquakes generated tsunami waves of up to 22 meters (72 feet) that engulfed the shores, killing at least 192 people—149 in Samoa, 34 in American Samoa, and 9 in Niuatoputapu, Tonga.
The devastation extended beyond human casualties with houses destroyed, cars swept out to sea, and some villages being virtually annihilated.
With over $200 million dollars (2009 value) in damages, the islands were ravaged both physically and economically.
Background image: Pago Pago. Overturned truck swept into harbor by receding water. (Source: Richard Madsen; NCEI Natural Hazards Image Database )
The deadly 2009 tsunami was triggered by at least two separate earthquakes occurring within 2–3 minutes of each other near the Tonga Trench (see the dashed/dotted red line on the map), one of the most seismically active areas in the world.
This is an extremely rare event, known as a “doublet.”
American Samoa
Since the earthquakes occurred so close in time, scientists have not been able to distinguish which earthquake occurred first or which caused a bigger tsunami.
However, the events of September 29 involved a magnitude 8.1 earthquake on a normal fault within the outer rise; and the other magnitude 8.0 earthquake occurred on the subduction zone as a thrust event.
Pago Pago Community Center. (Source: NCEI Natural Hazards Image Database )
Since the 2009 tsunami, Samoa has taken many preparedness measures including establishing a 24/7 National Earthquake and Tsunami Warning Center.
In 2017, UNESCO Intergovernmental Oceanographic Commission (IOC) recognized Samoa’s first UNESCO IOC Tsunami Ready community , a pilot project that recognizes tsunami mitigation, preparedness, and response activities.
Background image: Pago Pago Community Center. (Source: NCEI Natural Hazards Image Database )
2011 Tohoku, Japan
The tsunami caused by the earthquake that struck off the coast of Japan devastated more than 70 kilometers of coastline in Iwate prefecture in northeastern Japan. (Source: Katherine Mueller, International Federation of Red Cross; NCEI Natural Hazards Image Database )
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
The 2011 Tohoku Earthquake and Tsunami was the most expensive disaster in modern history, causing scientists and policy-makers to reconsider their earthquake and tsunami hazard assumptions.
On March 11, 2011, a magnitude (Mw) 9.1 earthquake struck off the northeast coast of Honshu on the Japan Trench.
A tsunami that was generated by the earthquake arrived at the coast within 30 minutes, overtopping seawalls and disabling three nuclear reactors within days.
A tug boat is among debris in Ofunato, Japan. (Source: Mass Communication Specialist 1st Class Matthew M. Bradley, U.S. Navy; NCEI Natural Hazards Image Database )
The 2011 Tohoku Earthquake and Tsunami event, often referred to as the Great East Japan earthquake and tsunami, resulted in over 18,000 dead, including several thousand victims who were never recovered.
Background image: A carport is destroyed near Onagawa, Ishinomaki. (Source: Shunichi Koshimura; NCEI Natural Hazards Image Database )
The deadly earthquake was the largest magnitude ever recorded in Japan and the third-largest in the world since 1900.
A Japanese home is seen adrift in the Pacific Ocean near Sendai, Japan. (Source: Mass Communication Specialist 3rd Class Dylan McCord, U.S. Navy; NCEI Natural Hazards Image Database )
Modeled tsunami amplitudes are displayed using a color scale, where blue is either zero or the smallest, and red is the highest, or greater than 3 meters. (Source: NOAA )
Map/Image: “Energy map”, or a modeled, mathematical colored surface representing the maximum rise in sea-level caused by the tsunami (see Deep-Ocean Tsunami Amplitude image above). Contoured lines with numbers indicate the modeled time (in hours) that the waves traveled from the source (red star). (Source: NOAA )
Japan
In Japan, the event resulted in the total destruction of more than 123,000 houses and damage to almost a million more.
Ninety-eight percent of the damage was attributed to the tsunami. The costs resulting from the earthquake and tsunami in Japan alone were estimated at $220 billion USD.
Damaged roads in the affected regions have made access to communities in need all the more challenging. This picture was taken outside Otsuchi in Iwate prefecture. (Source: Japanese Red Cross; NCEI Natural Hazards Image Database )
The damage makes the 2011 Tohoku / Great East Japan earthquake and tsunami the most expensive natural disaster in history.
Background image: An aerial view of damage to Sukuiso, Japan, a week after a 9.0 magnitude earthquake and subsequent tsunami devastated the area. (Source: Dylan McCord, U.S. Navy; NCEI Natural Hazards Image Database )
Indonesia
Fortunately, the loss of life outside of Japan was minimal (one death in Indonesia and one death in California) due to the Pacific Tsunami Warning System and its connections to national-level warning and evacuation systems.
An aerial view of damage to Rikuzentakata, Japan. (Source: Mass Communication Specialist 3rd Class Alexander Tidd, U.S. Navy; NCEI Natural Hazards Image Database )
California, United States
Harbor damage in Crescent City, California. (Source: Todd Williams, Cascadia GeoSciences; NCEI Natural Hazards Image Database )
2021 South Sandwich Islands
Because of the remoteness of the uninhabited South Sandwich Islands, no photos from the 2021 earthquakes or resulting tsunami exist. Pictured is nearby South Georgia Island where the tsunami signal was first observed. (Source: Getty Images)
Tsunami data from the NCEI/WDS Global Historical Tsunami Database . Note that in some cases, tsunami and earthquake damages and deaths could not be separated. (Source: NCEI)
On August 12, 2021, a series of powerful earthquakes shook the South Sandwich Islands. The initial earthquake measured 7.5 Mw. Just three minutes later, an 8.1 Mw quake followed, rupturing the shallow subduction zone.
The entire event lasted an unusually long 260 seconds. The 8.1 Mw quake is tied with an event in 1929 as the largest earthquake ever recorded in this region and the Atlantic Ocean as a whole.
The South Sandwich Islands are a group of extremely remote, very small, uninhabited islands located just north of Antarctica in the Southern Ocean.
Despite being partially covered with ice, the islands are the product of volcanic eruptions and are home to active volcanoes. The islands are also in an active earthquake zone due to their location in the Scotia Subduction Zone, a boundary where tectonic plates that make up Earth’s outermost layer collide.
Steam clouds rise from fumaroles near the summit of Mount Curry, on Zavodovski Island, in this aerial view from the south. Icebergs lie off the shores of the approximately 4.5-km-wide island, the northernmost of the South Sandwich Islands. (Source: HMS Endurance, courtesy of John Smellie, British Antarctic Survey; Global Volcanism Program )
Although the tsunami was not destructive, it was recorded at many coastal sea-level stations around the world, as far away as 10,000 kilometers (6,214 miles) from its origin.
After first reaching the nearby King Edward Point on South Georgia Island, with a maximum run-up height of around 75 centimeters (2.46 feet), smaller tsunami signals were observed as far away as Hawaii, Alaska, Mauritius, the Azores Islands, and eastern Madagascar.
The tsunami is one of the few events to be recorded in four out of the five oceans (Pacific, Atlantic, Indian, and Southern).
Map/Image: “Energy map”, or a modeled, mathematical colored surface representing the maximum rise in sea-level caused by the tsunami (see Deep-Ocean Tsunami Amplitude image above). Contoured lines with numbers indicate the modeled time (in hours) that the waves traveled from the source (red star). (Source: NOAA )
Modeled tsunami amplitudes are displayed using a color scale, where blue is either zero or the smallest, and red is the highest, or greater than 3 meters. (Source: NOAA )
Because the 8.1 Mw quake occurred so closely behind the 7.5 Mw event, the first quake had initially masked the second quake’s seismic signature.
Map: Pacific Ocean Observations
It was the unpredicted, global-spreading tsunami that gave scientists insight into the nature of the earthquake. Research models showed that the 7.5 Mw event would not have caused a tsunami of this extensive nature, so it helped reveal the larger, longer quake as the cause.
Map: West African Observations
Luckily, no one was injured and no damage occurred from either the quake or the tsunami.
Ongoing research on this complex event will help improve earthquake monitoring and tsunami warning systems in the future.
Map: Indian Ocean Observations
Guide: How to Use the Maps
Each tsunami event is accompanied by several maps. These maps are interactive, which means that you can click on a point on the map to display a box with more information, click on the +/- buttons to zoom in or out, or click and drag your mouse to move around the map.
Scroll left or right through the screenshots below to view event map features.
Map Key Glossary
Plate Boundary
Earthquakes are largely restricted to narrow zones around the globe. The Earth’s crust and outer mantle are fused together into a rigid, rocky layer about 62 miles thick known as the lithosphere. The lithosphere encases the entire Earth, but is broken into pieces, or plates, that move past, into, or away from each other. The plates can move based on changes happening below the surface of the Earth. Where plates interact, tremendous stresses are built up and released, which can cause earthquakes.
Epicenter
The epicenter is the place on the Earth’s surface where an earthquake began. Epicentral area is the location where the earthquake occured and as a result, is typically the location with the most damage.
Eyewitness measurement
Scientists often rely on eyewitness accounts and recollections to reconstruct tsunami behavior, heights and inundation distances.
Tide-gauge measurement
A coastal tide gauge is a piece of equipment used for measuring the changes in sea level with respect to a height reference surface. Tide gauges are able to detect the rise in the sea level that a tsunami would produce.
Deep-ocean bottom pressure recorder
Deep-ocean bottom pressure recorders on the seafloor can confirm the existence of tsunami waves. They observe and record changes in sea level out in the deep ocean. Data are transmitted to a nearby surface buoy, which relays the message to tsunami warning centers via satellite that a tsunami is observed. The DART® system consists of a seafloor bottom pressure recording system used by NOAA for early detection and real-time reporting of tsunamis before they reach land.
Post-tsunami survey measurement
Post-tsunami surveys record evidence left immediately after a tsunami has struck. This can include measurement of high water marks and debris or sediment deposited onshore, among others.
Learn More
NCEI: On This Day Event Series
- On This Day: Great Alaska Earthquake and Tsunami (NCEI News)
- On This Day: 1960 Chilean Earthquake and Tsunami (NCEI News)
- On This Day: 1992 Nicaragua Tsunami (NCEI News)
- On This Day: 2009 Samoa Islands Tsunami (NCEI News)
- On This Day: 2011 Tohoku Earthquake and Tsunami (NCEI News)
- On This Day: 2021 South Sandwich Islands Tsunami (NCEI News)