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U.S. Tsunami Warning System Struggles with Budget and Staffing Reductions Facing Additional Challenges

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This month, nine seismic observatories in Alaska are expected to lose power, leaving tsunami forecasters without essential data to assess whether an earthquake could generate destructive waves heading toward the West Coast.

These stations depended on federal support that lapsed last year, and the Trump administration declined to renew it this fall. Information from the observatories is vital for researchers studying the size and shape of earthquakes occurring along the Alaska subduction zone, a fault known for producing some of the globe’s most potent earthquakes, thereby endangering California, Oregon, Washington, and Hawaii.

Michael West, director of the Alaska Earthquake Center, mentioned that the removal of the observatory could postpone the notification of a potential tsunami in Alaska’s coastal regions, with areas like Washington state potentially facing less precise forecasts.

“Statistically, the last tsunami in the United States originated from Alaska, and the next one will likely follow suit,” he stated.

This is yet another setback for the U.S. tsunami warning system, which has already been grappling with underfunding and staff shortages. Researchers are alarmed that the network might be on the verge of collapse.

“The entire tsunami warning system is regressing,” West said. “There are numerous issues at play.”

In the United States, there are two tsunami warning centers that operate continuously—one in Palmer, Alaska, and another in Honolulu. These centers provide forecasts that assist emergency managers in deciding if coastal evacuations are necessary after an earthquake. Data from Alaska’s seismic stations has historically been integral to the center’s operations.

Both centers are already experiencing staffing shortages; currently, only 11 of the 20 full-time positions at the Alaska center are filled, as reported by Tom Fahey, union legislative director for the National Weather Service Employees Organization. Meanwhile, in Hawaii, four out of 16 positions remain vacant. (Fahey indicated both sites are looking to hire scientists.)

Furthermore, funding for the National Tsunami Hazard Reduction Program, which finances the majority of state tsunami risk reduction initiatives, has been slashed by the National Oceanic and Atmospheric Administration (NOAA). In 2025, a mere $4 million was allocated—significantly less than the historic $6 million provided.

“You’re on life support,” West remarked regarding the program.

Tsunami evacuation route sign in Bolinas, California.Steven Lamb/San Francisco Chronicle, via Getty Images file

Additionally, due to probationary layoffs in February under the Trump administration, NOAA terminated Corinna Allen, director of the National Weather Service’s tsunami program, as reported by Washington state seismologist Harold Tobin. Allen, who had just recently joined the agency, refrained from commenting through a spokesperson for her new employer, the Washington State Department of Natural Resources.

These recent reductions coincide with the Trump administration’s broader strategy to cut federal spending, especially on science and climate research. NOAA enacted cuts in February, including hundreds of layoffs, reductions in weather balloon launches, and a halt to research on climate and weather disaster costs.

Most of the closed seismic stations in Alaska are located in isolated regions of the Aleutian Islands. West noted that this chain extends westward from the Alaska Peninsula towards Russia, following a subduction zone on the ocean floor. KHNS is Alaska’s public radio station, which first reported the news of the stations going offline.

A NOAA grant of approximately $300,000 annually had supported these stations. The Alaska Earthquake Center sought a new grant to continue operations through 2028 but was turned down, according to emails between West and NOAA officials examined by NBC News.

NOAA spokesperson Kim Doster stated that the federal agency ceased funding in 2024 under the Biden administration. Uma Bhatt, a professor at the University of Alaska Fairbanks and deputy director of the institute managing the grant, mentioned that the University of Alaska Fairbanks managed to raise funds in the spring to keep the program running for another year, anticipating that federal support would follow. Unfortunately, that funding never materialized.

“The removal of these observations does not hinder the Tsunami Warning Center from fulfilling its mission,” Doster remarked. “AEC [Alaska Earthquake Center] is one among many partners aiding the National Weather Service’s tsunami initiatives, and the NWS continues using various methods to guarantee the collection of seismic data throughout Alaska.”

The White House has not responded to requests for comment.

West indicated that the Alaska Earthquake Center supplies a significant portion of the data utilized for tsunami alerts in the state. The grant funding the nine seismic stations also facilitated a data stream that included inputs from the center’s additional sensors. Consequently, tsunami warning centers across the nation will no longer have direct access to that data feed.

West noted that the stations spread across the Aleutian Islands cover an extensive geographical expanse.

“There’s nothing else in the vicinity,” he pointed out. “It’s not like there’s another piece of equipment 20 miles away; there aren’t even any roads.”

West intends to abandon the station later this month but will leave the equipment behind.

Washington State’s Tobin expressed concerns that the closures “might lead to delays and diminish the quality of tsunami warnings.”

“Surveillance is sparse in this region. We need to be vigilant,” he remarked, adding, “These programs often operate unnoticed until a critical event occurs.”

The Alaska-Aleutian subduction zone stands out as one of the most active fault lines globally, having previously triggered substantial tsunamis. In 1964, a magnitude 9.2 earthquake unleashed a tsunami that claimed 124 lives, with 13 fatalities in California and five in Oregon. The majority of California’s casualties occurred in Crescent City, where waves reaching 6 meters obliterated 29 city blocks, according to the city’s website.

Experts in tsunami studies emphasized that the observatory stations in the Aleutian Islands are crucial for the swift identification of nearby earthquakes. The closer an earthquake is to a sensor, the lower the uncertainty regarding the resulting tsunami.

NOAA’s Tsunami Warning Center aims to generate an initial forecast within five minutes, which is vital for local communities. (In the event of a significant earthquake in the Aleutian Islands, the first waves could reach nearby Alaskan towns within minutes.) The only data available quickly enough to facilitate these initial projections comes from seismic signals, as opposed to buoy-mounted tide gauges or pressure sensors.

Subsequently, the warning center provides a more detailed wave height prediction about 40 minutes later. Daniel Ungaard, director of tsunami programs at the Washington Geological Survey, noted that without sensors in Alaska, there would be increased uncertainty about projected wave heights, complicating decisions on whether to initiate evacuations along Washington’s coastline.

“We strive to avoid unnecessary evacuations,” he explained, emphasizing that unwarranted alerts could result in wasted time, resources, and credibility.

Last year, tsunami warning centers nationwide were inundated. In December, a magnitude 7.0 earthquake near Cape Mendocino, California, activated a tsunami warning along the coast. July saw an 8.8 magnitude earthquake off the coast of Russia’s Kamchatka Peninsula, prompting a widespread warning along the U.S. West Coast, just west of the Aleutian Islands.

NOAA has been instrumental in establishing many seismic observatories that form part of the Alaska Earthquake Center network. However, West mentioned that over the past two decades, the agency has decreased its support. The nine bases developed by NOAA were decommissioned in 2013.

“Now is the moment for NOAA to decide on their commitment,” he declared. “I aim to ignite a conversation about tsunami preparedness in the United States, ensuring it doesn’t merely arise in response to the next catastrophic tsunami.”

Source: www.nbcnews.com

Kamchatka Earthquake Response Demonstrates Enhanced Tsunami Warning System

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The coastline of Shiogama, Japan, where a tsunami warning was issued following a significant earthquake

Asahi Shimbun via Getty Images

On July 29, a strong earthquake struck near Russia’s Kamchatka Peninsula, prompting a quick tsunami warning that allowed millions to evacuate safely. Although no unexpected waves materialized, the swift response demonstrates the progress made in tsunami science since the devastating tsunamis in 2004 and 2011, which cost tens of thousands of lives.

“This is an excellent accomplishment built on lessons learned from previous incidents,” said Ravindra Jayaratne, a researcher at the University of East London, UK.

The efficiency of the warning system can be attributed to an enhanced network of tsunami detection sensors. This includes seismometers that detect earthquake tremors and a series of buoys managed by the US National Oceanic and Atmospheric Administration, which assess wave heights and relay crucial information to satellites. Improved modeling techniques enable researchers at the Tsunami Warning Office to swiftly predict and disseminate alerts about wave impact locations and times.

On the day of the event, tsunami offices across the Pacific region were able to issue alerts almost immediately after the 8.8 magnitude earthquake was detected—recorded as the strongest ever. In Japan, approximately 2 million individuals evacuated from coastal regions, with others doing the same in Hawaii and even in Chile, located just south of the US west coast.

“The reaction was prompt and effective,” noted David Tappin from the British Geological Survey. He added, however, that despite the earthquake’s intensity, it resulted in minimal wave activity and flooding, highlighting the need for improved predictive capabilities regarding flood events based on early detection of tremors and wave conditions.

Jayaratne also pointed out that regions prone to tsunamis, such as Bangladesh and Sri Lanka, lack a robust warning system and adequate public awareness of potential risks. “History shows that advanced detection technologies are only useful when accompanied by effective public communication and comprehensive evacuation strategies,” he said. “Coastal communities must conduct drills regularly to enhance public awareness and ensure warnings reach those in need through various channels.”

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Source: www.newscientist.com

The Limited Impact of the Tsunami on the U.S. Does Not Indicate an Inaccurate Forecast

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The 8.8 magnitude earthquake off the coast of Russia’s Kamchatka Peninsula generated water waves traveling at jetliner speeds toward Hawaii, California, and Washington states on Wednesday.

Yet, when the tsunami reached the U.S., it appears not to have inflicted widespread devastation, with some areas where warnings were issued showing no signs of significant flooding.

This doesn’t mean the tsunami was a “bust” or poorly predicted, according to earthquake and tsunami researchers.

“When you hear ‘tsunami warning,’ people often think of dramatic scenes from movies, and when it arrives at just three feet, they might wonder, ‘What’s going on?’,” remarked Harold Tobin, director of the Pacific Northwest Earthquake Network and professor at the University of Washington. “We should view this as a success; we received a warning, but the situation wasn’t catastrophic.”

Here’s what you should know.

How intense was the Kamchatka earthquake? What caused the initial discrepancies?

Initially, the US Geological Survey assessed the Kamchatka earthquake at magnitude 8.0, which was later adjusted to 8.8.

“It’s not unusual for major earthquakes to see such adjustments in the first moments,” Tobin explained. “Our standard methods for calculating earthquake sizes can quickly saturate, akin to turning up the volume on a speaker until it distorts.

A buoy measuring the quake, located approximately 275 miles southeast of the Kamchatka Peninsula, gave the first signs of the earthquake, showing bigger waves than the initial report.

This buoy belongs to the National Oceanic and Atmospheric Administration’s DART (Deep Ocean Assessment and Reporting) system and is connected to a submarine pressure sensor roughly four miles deep.

That sensor detected waves measuring 90 centimeters (over 35 inches), which caught the attention of tsunami researchers.

Vasily Titov, a senior tsunami modeler at NOAA’s Pacific Ocean Environment Research Institute, noted:

Titov reflected on the 2011 Tohoku earthquake and tsunami, which tragically claimed nearly 16,000 lives in Japan.

Subsequent earthquake models confirmed the Wednesday earthquake’s magnitude as 8.8, as detailed by the USGS calculator.

In comparison, Tohoku was significantly larger.

Tobin estimated that the energy released during the Kamchatka quake was two to three times less than that in Japan, with the tsunami generated there being approximately three times as severe.

He further noted that the Tohoku event “created a notably large seafloor displacement.”

Tobin speculated that the Kamchatka quake likely had less seafloor displacement than what could occur in a worst-case 8.8 scenario, though more research is needed for substantiation.

Emergency services experts assess damage on Sakhalin Island in the Far East post-earthquake.Russia’s Ministry of Emergency via Getty Images / AFP

How did researchers generate predictions? How accurate were they?

Within two hours, researchers produced tsunami predictions for various “warning points” along both the Pacific and US coasts, forecasting tidal gauge and flood levels.

The tsunami took around eight hours to reach Hawaii and twelve hours to arrive at the California coast.

Titov, who assisted in developing the model used by predictors in the National Tsunami Warning Centers in Hawaii and Alaska, explained that the model relies on seismic data and a network of over 70 DART buoys along the Pacific edge. The U.S. operates more than half of these buoys.

Titov indicated that the model projected tsunami waves hitting Hawaii’s North Shore region at approximately two meters.

“Hawaii was predicted to have waves of about 2 meters [6.5 feet], and actual measurements were around 150 centimeters, or 1.5 meters (5 feet). That aligns perfectly with our expectations,” Titov stated.

A similar trend was observed in parts of California, according to Titov.

As assessments of flooding continue to come in, it takes time to determine how well the model performed.

“We know there were floods in Hawaii. We can’t ascertain the full extent yet, but initial reports seem to align closely with our predictions,” Titov shared.

On Wednesday at the Pacifica Municipal Pier Coastline in California, tsunami alerts were triggered following the earthquake.Tayfun Coskun/Anadolu via Getty Images

Why did residents in Hawaii evacuate for a 5-foot wave?

Yong Wei, a tsunami modeler and senior research scientist at the University of Washington and NOAA’s tsunami research center, indicated that 1.5 meters (5 feet) of tsunami waves could be highly perilous, particularly in Hawaii’s shallow waters.

Tsunami waves carry significantly more energy than typical wind-driven waves, possessing shorter wavelengths and durations between waves, resulting in slower speeds.

Wei noted that tsunami waves of this stature could surge several meters inland, producing hazardous currents and endangering boats and other objects.

Visitors stand on the balcony of the Alohilani Resort facing Waikiki Beach in Hawaii, responding to warnings of potential tsunami waves.Nicola Groom / Reuters

“People can get hurt. If you ignore the warning and stay, even a wave of two meters can be deadly,” Wei warned. “Being on the beach can expose you to powerful currents that may pull you into the ocean, which can lead to fatalities.”

Tobin expressed that he viewed the initial warning as conservative yet necessary.

“It’s essential not to belittle warnings. If nothing happens, people shouldn’t think, ‘Oh, we had alerts and nothing transpired.’ Warnings need to be cautious, allowing for some margin of error.”

Was this a significant event?

No. The Kamchatka Peninsula has a long history of seismic activity.

“This area has been slated for another earthquake, with several occurring recently, which indicates a heightened risk,” researchers noted.

In 1952, prior to a robust understanding of plate tectonics, a 9.0 magnitude quake struck the Kamchatka Peninsula in a similar location, resulting in a tsunami that impacted the town of Severokrilsk.

“The Russian populace was caught off guard. It was an immensely powerful quake, leading to a massive tsunami, and they were unprepared,” McInnes shared.

McInnes explained that the tsunami measured between 30 to 60 feet in height in the southern section of the peninsula.

“Thousands perished, and the town suffered considerable destruction,” stated Joanne Bourgeois, a professor emeritus of sedimentology at the University of Washington.

How will the tsunami warning system function if an earthquake threatens your area?

The Kamchatka tsunami arose from a massive earthquake along a subduction zone fault, where one tectonic plate is pushed below another. A comparable fault exists offshore the U.S. West Coast, known as the Cascadia Subduction Zone, stretching from Northern California to Northern Vancouver Island.

“It’s akin to a mirrored image of the Pacific Ocean,” remarked Tobin. “The relatively shallow depth of 8.8 in Cascadia is certainly plausible for a scenario here.”

In fact, Cascadia has the potential to produce significantly larger earthquakes, as modeling suggests it could generate tsunami waves reaching heights of 100 feet.

Typically, earthquakes in subduction zones yield tsunamis that reach the coast within 30 minutes to an hour, and predictions are developing better methods for estimating tsunami impacts along the U.S. West Coast before flooding occurs.

Titov emphasized that enhancing predictions will necessitate advancements in underwater sensors, improved computing infrastructure, and AI algorithms.

Tobin noted that the success of Tuesday’s tsunami warning should inspire more investments in underwater sensors and earthquake monitoring stations along the subduction zones.

“This incident highlights the significant role of NOAA and USGS. Many questioned these agencies’ relevance, but without NOAA, no alert would have been issued. The next warning could be for a more imminent threat. They truly demonstrated their importance,” he asserted.

Source: www.nbcnews.com

Tsunami Advisory Issued for Alaska Following 7.3 Magnitude Earthquake off the Aleutian Islands

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Alaska’s coastal regions were on alert for a tsunami Wednesday following a 7.3 magnitude earthquake that hit the Ariuya Islands, according to officials.

The earthquake occurred at 12:38 PM local time (4:38 PM ET), with its epicenter located 55 miles south of Sandpoint, a community on Popf Island. The quake was recorded at a depth of 12 miles.

Tsunami data was not immediately available, and effects for Kodiak Island were not anticipated until 2:40 PM local time (6:40 PM ET).

Although no large-scale flooding is expected, the Tsunami Warning Center stated that dangerous currents and waves could pose risks to those in close proximity.

The initial tsunami warning has since been adjusted to a tsunami advisory.

These advisories span various coastlines, from Unimak Pass in the Aleutians to the entrance of Kennedy, located 40 miles south of Homer.

Emergency personnel in Kodiak, a city of around 5,500 that lies about 250 miles south of Anchorage, announced that shelters would be opened and sirens sounded prior to the warning being downgraded.

“The sirens are sounding, and remain vigilant if you’re near the coast,” Kodiak Island Emergency Management advised on social media.

Emergency officials reported no threat to Anchorage, Alaska’s largest city, following the earthquake.

Debi Schmidt, the city manager of Sand Point, discussed the earthquake with NBC affiliate Ktuu, describing it as the strongest quake she had ever experienced.

“I was at home for lunch when the house began to shake; things were falling, and the cupboard door swung open,” she recounted to the station. “Fortunately, there was no damage.”

Source: www.nbcnews.com

A 100-Foot “Tsunami” Could Strike the US at Any Moment — and That’s Only the Start

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The Cascadia subduction zone, a vast fault line extending from Northern California to British Columbia, has remained unsettlingly silent for 300 years. Should it finally rupture, a substantial earthquake is anticipated to shake the Pacific Northwest for several minutes.

Even more alarming, the resulting tsunami could generate waves reaching up to 100 feet (30 meters), wreaking havoc along the coast.

New research published in Proceedings of the National Academy of Sciences indicates that this event would only mark the onset of Cascadia’s cataclysm.

As if waves equivalent in size to those of the 2004 Boxing Day tsunami weren’t frightening enough, the latest analysis reveals land along the coast could subside by more than 2.5 meters (8 feet) almost instantaneously.

“We often discuss climate-induced sea level rises at a rate of 3-4 millimeters annually,” noted Professor Tina Dura, the lead author of the study, in an interview with BBC Science Focus. “But here, we could witness a 2-meter sea level rise in just a few minutes. Why aren’t we talking about that more?”

What Happens When Cascadia Erupts?

The Cascadia subduction zone represents the boundary where the oceanic Juan de Fuca plate descends beneath the North American plate. However, these tectonic plates tend to get stuck rather than moving freely. When they finally lock in place, immense pressure builds over centuries.

Once this pressure is released, it results in a formidable earthquake.

Cascadia is capable of producing earthquakes reaching magnitudes of 9.0 or higher, historically experienced once every 450-500 years. The last event occurred on January 26, 1700, with estimates suggesting its magnitude was likely between 8.7 and 9.2.

According to the US National Earthquake Hazard Model, there is a 15% chance of experiencing earthquakes of magnitude 8.0 or greater in this zone over the next 50 years.

Planning exercises conducted by the Federal Emergency Management Agency in 2022 predicted that these tremors could directly result in 5,800 fatalities, with an additional 8,000 lives lost to the tsunami.

Over 100,000 individuals could be injured, and more than 618,000 buildings could be damaged or destroyed, impacting over 2,000 schools and 100 critical facilities. The estimated economic impact: $134 billion.

“This will definitely be a catastrophic event for the United States,” Dura stated.

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Aftershocks That Will Last for Decades

While the earthquake and tsunami will be devastating on their own, Dura and her colleagues warn that the long-term consequences could be equally destructive.

By integrating historical records of past Cascadia earthquakes with geological data from numerical models, the researchers assessed how coastal landscapes may be altered due to subsidence from the sudden sinking of land during an earthquake.

If a Cascadia earthquake were to occur today, land at 24 estuaries stretching from southern Washington to northern California could drop anywhere from 0.23 to 2.67 meters (0.76 to 8.76 feet) in minutes.

This could significantly expand the 100-year flood plain by 300 square kilometers (115 square miles), meaning more homes, roads, and infrastructure would fall into at-risk areas. In a severe subsidence scenario, flood exposure could more than double.

“It’s a dual threat,” Dura explained. “The tsunami will be catastrophic, but we also know that some locations will face extreme impacts, while others will experience serious repercussions due to the geographic layout of the coast.”

Located in the US Pacific Northwest and southwest British Columbia, the Cascadia subduction zone last shifted in 1700, resulting in a major earthquake. – John Wesley Powell Analysis and Synthesis/Center for USGS

In 1700, the infrastructure suffered minimal damage. Today, the region is filled with critical systems that remain vulnerable to inundation. These include five airports, 18 emergency facilities (such as schools, hospitals, fire stations), eight wastewater treatment plants, one current, and 57 potential contamination sources like gas stations and chemical storages.

Submerged roads and flooded emergency hubs could severely impede recovery, while saltwater intrusion could damage farmland, resulting in long-term economic repercussions.

Furthermore, natural flood defenses like intertidal wetlands could be inundated or eroded, weakening protection against future storm surges. Rising tidal ranges could compound high-water flooding and may exacerbate the erosion of sandy coastlines.

“Once the tsunami hits and eventually recedes, the land will remain at a lower level,” Dura noted. “The flood plain footprint will evolve over decades, and even centuries.”

The Sooner It Hits, The Better

While the occurrence of an earthquake is inherently negative, the longer Cascadia remains quiet, the worse the ultimate disaster may be.

Researchers simulated what would occur if an earthquake were to strike in 2100 instead of today. With climate change, rising sea levels could exacerbate the consequences.

The global average sea level has already seen an increase of 21-24 cm (8-9 inches) since 1880, as reported by the National Oceanic and Atmospheric Administration. Projections suggest an increase of at least 20 cm (2 feet) by 2100.

However, the situation in Cascadia is somewhat complex. As the Juan de Fuca plate slides beneath the North American plates, the land on the continent is gradually uplifted, temporarily masking the implications of global sea level rise.

This slow upward thrust won’t last indefinitely. Eventually, climate change will catch up, leading to a rise in sea levels in the Pacific Northwest on par with other areas. Consequently, the two challenges—tectonic and climatic—are converging.

“You can imagine that when the land subsides during the next earthquake, you suddenly have to contend with centuries of comparable sea level rise,” Dura remarked.

By 2100, even without earthquakes, researchers estimate that flood plains could expand by 100 square kilometers (40 square miles). This, combined with subsidence from a potential earthquake, could triple flood exposure compared to today, resulting in a flood plain enlargement of up to 370 square kilometers (145 square miles).

How Can You Prepare?

What steps can communities take to prepare for this complex threat that combines earthquakes, tsunamis, subsidence, and sea level rise?

Dura admitted that there is no straightforward solution.

“Cascadia presents a unique challenge due to its prolonged quietude,” she said. “It’s tough to keep residents informed about the risks without inciting undue panic. How do you prepare without instilling fear?”

As an initial measure, Dura’s team suggests incorporating their findings into flood hazard and tsunami maps and collaborating across agencies to enhance preparedness.

Key actions include identifying critical infrastructure in future flood zones, planning for relocation or adaptation, promoting nature-based solutions by raising public awareness, restoring wetlands, and carefully considering new developments in high-risk areas.

Is all hope lost? Dura insists that time is of the essence.

“There are certainly individuals actively working on this. I don’t want to undermine their efforts,” she said. “But we need more people engaged in the issue. Perhaps we lack adequate resources, funding, or personnel, but collective efforts are being made, and significant new research is emerging.”

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About Our Experts

Tina Dura is an assistant professor of natural disasters at Virginia Tech in the United States. She specializes in subduction zone paleogeography, integrating methodologies from coastal stratigraphy, sedimentology, microbiology, paleoconservation, geophysics, and sediment transport modeling, as well as sea level research to reconstruct the extensive history of subsidence along the coastal region.

Source: www.sciencefocus.com

Gigantic Clifftop Boulder in Tonga Reveals Evidence of an Ancient Tsunami

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Locally referred to as Makarahi, meaning “big rock,” this boulder was displaced over 200 m inland by a tsunami approximately 7,000 years ago.

Limestone rock Makarahi. Image credits: Kohler et al. , doi: 10.1016/j.margeo.2025.107567.

The Makarahi boulder measures 14 x 12 x 6.7 m and weighs nearly 1,200 tons, making it the largest known boulder located atop a cliff and one of the largest vibration-transport boulders globally.

This limestone formation is situated 200 meters away from the coastline on the southern shore of Tongatapu, Tonga.

“Our research focused on the southern part of Tongatapu Island, examining coastal cliffs that show signs of past tsunamis,” stated Martin Kohler, a Ph.D. candidate at the University of Queensland.

“At the end of our fieldwork day, while conversing with some local farmers, they pointed us toward this rock.”

“I was truly astonished. It was found inland, outside our designated research area, indicating it must have been moved there by a massive tsunami.”

“It was remarkable to witness this large boulder enveloped in lush vegetation.”

“We created a 3D model before returning to the coast to identify a location from which boulders could be dislodged from cliffs over 30 meters high.”

Through numerical modeling, the researchers determined that a wave height of roughly 50 m lasting about 90 seconds would be required to transport the Makarahi boulder from its original cliff edge to its new location.

“The University of Queensland has provided a fantastic opportunity to explore the forces shaping our world,” remarked Dr. Annie Lau, a coastal geomorphologist at the institution.

“The recent tsunami in Tonga in 2022 resulted in six fatalities and extensive damage.”

“Gaining insights into extreme past events is crucial for preparing and assessing risks related to current and future hazards.”

“The findings concerning the Makarahi boulder offer evidence of Holocene Pacific tsunamis that have occurred since about 11,700 years ago.”

“This analysis will enhance our understanding of rock wave transport and improve coastal hazard assessments in tsunami-affected regions worldwide.”

The team’s study is published in the journal Marine Geology.

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Martin Kohler et al. 2025. Investigating the world’s highest boulder atop a cliff: preliminary insights and numerical simulations of transport on cliffs ranging from 30-40 m in Tongatapu (Tonga). Marine Geology 487, 107567; doi:10.1016/j.margeo.2025.107567

Source: www.sci.news

Cretaceous Marine Deposits Reveal Evidence of a Massive Ancient Tsunami

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Significant amber deposits found in northern Japan may have been propelled from the forest into the sea by tsunamis occurring between 116 million and 114 million years ago during the early Cretaceous period. This is according to a recent study conducted by geological surveys at Japan and Chuo University.

Amber deposits from Sichuan Quarry in Hokkaido, northern Japan. Image credit: Kubota et al. , doi: 10.1038/s41598-025-96498-2.

Identifying traces of ancient tsunamis can be challenging, as the powerful waves tend to reshape coastlines. The sediment left behind often resembles deposits created by other high-energy events, like storms.

Nevertheless, amber, which originates on land and is then transported to the sea, acts as a historical record of tsunami occurrences, illuminating the physical processes influencing sediment movement during these events.

“A tsunami is a destructive ocean wave primarily caused by significant changes in submarine or coastal crust, as well as impacts from asteroids,” explains Dr. Aya Kubota, a researcher at geological surveys at Japan and Chuo University.

“They have been extensively studied during the Holocene (the last 11,700 years) due to their relevance in disaster prevention.”

“Aside from asteroid sediments, accurately identifying ancient tsunamis before major vegetation growth is extremely difficult for two key reasons.”

“First, coastal tsunami deposits are easily eroded in their dynamic environments. Second, well-defined criteria for identifying tsunami deposits have not been established, as they can be difficult to differentiate from other high-energy coastal events, such as cyclones.”

In their research, Dr. Kubota and colleagues examined amber-rich silica deposits from the Shiko River Quarry in northern Hokkaido, which formed during the early Cretaceous period around 115 million years ago.

Using fluorescence imaging, the authors discovered that the amber samples exhibited clear deformation in what is known as the flame structure. This occurs when the amber is still pliable at the time of deposition, allowing it to change shape before solidifying.

This suggests that a substantial quantity of amber was swiftly transported from land into the open ocean due to the backwash from one or more tsunamis, experiencing minimal exposure to air.

The amber then settled at the seabed, becoming covered with a layer of silt, which helped to preserve it.

“Other terrestrial sediments carried into open water could be instrumental in studying significant ancient catastrophic events, such as tsunamis,” the researchers concluded.

Their study was published in the journal Scientific Reports on May 15th.

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A. Kubota et al. 2025. Amber, a deep-sea sediment from the Cretaceous period, reveals a massive tsunami. Sci Rep 15, 14298; doi:10.1038/s41598-025-96498-2

Source: www.sci.news

After days of observation, scientists confirm a 650-foot-high tsunami formed in Greenland.

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summary

  • Seismologists detected unusual vibrations and determined that a 650-foot-high tsunami had occurred in Greenland.
  • The tsunami was caused by melting glacial ice that triggered landslides and washed away water in Greenland's fjords.
  • The waves it created continued to travel back and forth across the fjord for nine days.

Last September, seismologists around the world detected vibrations never before observed.

The monotony seemed to come from Greenland and continued for nine days.

“We saw some very strange signals at some stations in the north that we'd never seen before,” said Karl Ebeling, a seismologist at the Scripps Institution of Oceanography at the University of California, San Diego.

Shortly after the vibrations began, a cruise ship sailing near a Greenland fjord noticed that a key landmark on the remote island of Ella, a scientific research and Danish military dog ​​sled patrol base, had been destroyed.

The event drew an international group of seismologists, the Danish military and oceanographers into the mystery: what struck the island, and where did it come from?

On Thursday, the researchers They published their findings in the journal Science.The island was hit by one of the largest tsunamis on record, leaving a scar about 650 feet high.

It was the result of a rare series of cascading events caused by climate change.

The researchers traced the initial trigger to the collapse of a glacier tongue that had been thinned by rising temperatures. This destabilized the steep mountainside, sending an avalanche of rock and ice into Greenland's deep Dikson Fjord. Massive amounts of water were displaced, causing towering waves to move across the narrow fjord, about a mile and a half wide.

The tsunami, at least as high as the Statue of Liberty, surged up the steep rock faces along the fjord and, because the landslide struck the waterway at a nearly 90-degree angle, sent waves circling the channel for nine days — a phenomenon scientists call a seiche.

“No one has ever seen anything like this,” said Christian Svennevig, lead author of the study and a geologist and senior research scientist at the Geological Survey of Denmark and Greenland.

The findings are the result of a complex year-long investigation. The team determined that Ella Island, about 45 miles from the landslide site, was hit by a tsunami at least 13 feet high.

Tourists visit the island from time to time.

“The cruise ship had been docked off the coast just a few days before,” Svennevig said. “We were really lucky that no one was there when it happened.”

The seiche was the longest scientists had ever observed: Until now, tsunamis generated by landslides have typically produced waves that dissipate within a few hours.

“This is really a cascade of events that has never been observed before,” said Alice Gabriel, co-author of the study. “The Earth is a very dynamic system, and we're currently at a stage where this very delicate balance is being disrupted pretty dramatically by climate change.”

Tsunamis triggered by landslides occur more frequently than many people realize and are a danger to people living and working in some Arctic and sub-Arctic regions.

In 2017, a landslide triggered a tsunami that killed four people and destroyed 11 homes. Attacked the village of Ngaatsiaq in West GreenlandThe tsunami was estimated to be at least 300 feet high. Two villages were abandoned in the aftermath of the tsunami due to fears of further landslides, and Svennevig said hundreds of people remain evacuated.

Bretwood “Higg” Higman, an Alaska geologist who studies landslide tsunamis but was not involved in the new study, said evidence suggests landslide tsunamis are a growing problem, but more research is needed.

“I'm pretty confident that these events are becoming more and more frequent,” he said. “Exactly how frequent these events are and can we predict the future? We're not there yet.”

Higman said he thought the Greenland study's researchers were “spot on” and that the research was an important example of how dangerous landslide-induced tsunamis could be.

The Arctic and sub-Arctic regions are warming two to three times faster than the rest of the Earth. As the ice melts, the exposed, dark surface absorbs more sunlight. Warming is triggering three dynamics that could make landslides more frequent in glacial regions, Higman said.

First, rising temperatures are eroding the permafrost within rock formations, weakening slopes and making them more susceptible to collapse. Second, warming is thinning the glaciers that support the rock slopes. Without the ice, sudden collapses could occur. Third, climate change is increasing the likelihood of heavy rains, which are the biggest risk factor for landslides because saturated rocks and soils become more slippery.

Higman has compiled a list of Alaska's slopes that are at risk for landslides that could trigger tsunamis. He said there are dozens of sites of concern that need further study, some of which are near populated areas where a landslide could be catastrophic.

“We're in an awkward position: Scientists know something, but they don't know enough to provide certainty to take action,” Higman said.

Last month, the U.S. Geological Survey reported a 56-foot-high landslide tsunami in Alaska's Pedersen Lagoon. Higman visited the site and believes the tsunami was larger than initially predicted.

Globally, risks are growing due to expanding development in some polar regions and increased visitation by miners, shippers and tourists, Svennevig said.

“At the same time as the population increases, the risk of landslides, geological hazards also increases,” he said. “It's an unfortunate combination.”

Source: www.nbcnews.com

Indonesian volcano eruption leads to tsunami warning and evacuation orders

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Indonesian authorities issued a tsunami warning Wednesday after the eruption of Mount Luang sent volcanic ash thousands of feet into the air. Authorities ordered more than 11,000 people to leave the area.

Indonesia’s Volcanology and Geological Hazard Mitigation Center said there were at least five major eruptions in the past 24 hours at a volcano on the northern side of Sulawesi island. Authorities raised the eruption alert to the highest level.

Mount Luang spews hot lava and smoke on the north side of Indonesia’s Sulawesi island on Wednesday.
Center for Volcanology and Geological Hazard Mitigation/via AFP – Getty Images

At least 800 residents left the area early Wednesday.

Indonesia, an archipelago of 270 million people, has 120 active volcanoes. It is prone to volcanic activity because it is located along the Pacific Ring of Fire, a series of horseshoe-shaped seismic faults around the Pacific Ocean.

Officials urged tourists and others to stay at least 6.0 miles from the 778-meter-high Luang Volcano.

Officials fear that parts of the volcano could collapse into the ocean, causing a tsunami, like the 1871 eruption.

Taglandan Island, to the northeast of the volcano, is once again in danger, and residents have been advised to evacuate.

Indonesia’s National Disaster Mitigation Agency announced that residents would be relocated to Manado, the nearest city on Sulawesi island, a six-hour boat ride away.

In 2018, the eruption of Indonesia’s Anak Krakatau volcano caused parts of the mountain to fall into the sea, triggering a tsunami along the coasts of Sumatra and Java, killing 430 people.

Source: www.nbcnews.com