Tsunami Research Articles

Computation Models for Tsunami Wave Propagation using Extended Cellular Automata

Using traditional models to simulate the propagation of large-scale tsunami waves leads to low accuracy and low efficiency. To ensure higher timing accuracy of tsunami wave spread, built an enhanced model that connects cellular automata with an existing model of tsunami waves. To determine the ideal time step value, our approach considers how time steps affect simulation accuracy. The spread of tsunami waves using a two-dimensional cellular automata model was used to test the model. Extending cellular automata (CA) models for tsunami wave propagation involves incorporating additional complexity and realism to better simulate the dynamics of these natural phenomena. The findings indicate that 1/4 of the time required for all of the cellular material to be traversed is the ideal time step for the tsunami wave spread global cellular automata simulation program. With a mean accuracy of 86.78% and a mean Kappa coefficient of 0.6443, this model demonstrated strong temporal and spatial consistency when compared to historical tsunami wave data from NOAA. Combining the Kappa coefficient with extended cellular automata (ECA) can be beneficial in various applications, particularly those involving classification tasks or spatial modeling. The earliest arrival tsunami wave spread can be predicted and simulated using this approach.

An Analytical Study of Tsunamis Generated by Submarine Landslides

In this work, the problem of tsunamis generated by underwater landslides is addressed. Two new solutions are derived in the framework of the linear shallow water equations and linear potential wave theory, respectively. Those solutions are analytical (1 + 1D) and another is semi-analytical (2 + 1D). The 1 + 1D model considers a solid body sliding over a sloping beach at a constant speed, and the 2 + 1D model considers a solid landslide that moves at a constant velocity on a flat bottom. The solution 1 + 1D is checked numerically using a different finite scheme. The 2 + 1D model examines the kinematic and geometric features of the landslide at a constant ocean depth and its influence on the generation of tsunamis. Landslide geometry significantly influences run-up height. Our results reveal a power law relationship between normalized run-up and landslide velocity within a realistic range and a negative power law for the landslide length–thickness. Additionally, a critical aspect ratio between the length and width of the sliding body is identified, which enhances the tsunamigenic process. Finally, the results show that the landslide shape does not have a decisive influence on the pattern of tsunami wave generation and propagation.

Physical experiments of waves generated by submerged steam eruptions with applications to volcanic tsunamis.

The tsunamigenic potential of underwater volcanic eruptions is not well understood, even though eruption-generated tsunamis can be devastating. To address how erupted steam bursts from underwater volcanoes generate tsunamis, we present the experiments, using pressurized steam injected vertically into a water tank. Results over various eruption conditions identify three eruption regimes, namely, shallow-, intermediate-, and deep-water eruptions, according to the combined effects of water depths, source strengths, and source durations. The transition between shallow and intermediate eruptions is characterized by critical depths maximizing tsunami wave heights, while the transition between intermediate and deep eruptions is characterized by containment depths inhibiting surface disturbances. Water depth and source intensity are the dominant factors controlling maximum wave amplitudes, more so than aspects of jet duration and condensation. These experiments and supporting dimensional analysis improve our understanding of how underwater volcanic eruptions form tsunamis, while also providing a complete dataset for advancing tsunami generation models.

Specification of INF01LE, INF03, and INF04LE infrasound sensors for the observation and detection of destructive geophysical events

When an object moves through the atmosphere, it induces pressure fluctuations. If the scale of the object’s movement spans several hundred meters to several kilometers, the period of the pressure fluctuation will range from several seconds to several tens of seconds, determined by the ratio of the scale to the speed of sound. These pressure fluctuations manifest within the frequency range between audible sound (> 20 Hz) and infrasound (< 20 Hz and > 3 mHz). The infrasonic waves, characterized by their low-frequency nature, present a promising avenue for long-distance remote sensing, particularly in the monitoring of geophysical events with the potential for widespread destruction, such as earthquakes and tsunamis. We developed sensors of both membrane and microphone types to monitor infrasound in lower or higher frequency, respectively. These sensors were installed on the Pacific side of Japan to observe infrasound mainly generated by tsunamis. The key advantage lies in the faster propagation speed of Lamb waves (∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim$$\\end{document}310 m/s) compared to that of tsunami waves (∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim$$\\end{document}200 m/s), making them a valuable precursor for timely detection. By combining with a small MEMS 3-axis accelerometers, this study explores the feasibility of identifying a sudden atmospheric pressure surge within the infrasonic frequency range, following a significant earthquake. The observed surge serves as a crucial indicator of the imminent arrival of large tsunami waves along the shoreline situated between the earthquake’s epicenter and the observation site. The practical implication of this detection methodology is profound, as it could potentially trigger early warning systems, leading to timely and targeted evacuations. These infrasound sensors effectively detected infrasound produced not only by tsunamis but also by volcanic eruptions, meteorite explosions, and so on. This research focuses on the significance of monitoring geophysical events in the infrasound frequency range by demonstrating the development of our infrasound sensors and the natural phenomena captured by these instruments. The study presents observational results based on three types of sensors (INF01LE, INF03, and INF04LE), each exhibiting a flat response within specific frequency ranges: 0.003 to 6.25 Hz, 0.1 to 100 Hz, and 0.1 to 100 Hz, respectively. These sensors have been rigorously tested across various natural phenomena to validate their effectiveness in capturing infrasonic waves. The findings of this research contribute to the growing body of knowledge on infrasonic wave coming from various geophysical disaster perspectives.

The Multi‐Segment Complexity of the 2024 MW ${M}_{W}$ 7.5 Noto Peninsula Earthquake Governs Tsunami Generation

AbstractThe 1 January 2024, moment magnitude 7.5 Noto Peninsula earthquake ruptured in complex ways, challenging analysis of its tsunami generation. We present tsunami models informed by a 6‐subevent centroid moment tensor (CMT) model obtained through Bayesian inversion of teleseismic and strong motion data. We identify two distinct bilateral rupture episodes. Initial, onshore rupture toward the southwest is followed by delayed re‐nucleation at the hypocenter, likely aided by fault weakening, causing significant seafloor uplift to the northeast. We construct a complex multi‐fault uplift model, validated against geodetic observations, that aligns with known fault system geometries and is critical in modeling the observed tsunami. The simulations can explain tsunami wave amplitude, timing, and polarity of the leading wave, which are crucial for tsunami early warning. Upon comparison with alternative source models and analysis of 2000 multi‐CMT ensemble solutions, we highlight the importance of incorporating complex source effects for realistic tsunami simulations.

Numerical modelling of pump-driven tsunami generation and fluid-structure-interaction in idealized urbanized coastal areas during run-up

Tsunami wave inundations are still one of the most devastating natural disasters worldwide. Tsunamis striking a settlement frequently devastate much of its infrastructure. In instances where infrastructure withstands the tsunami’s actions, it acts as a flow resistance for the wave’s run-up, altering inundation dynamics and flow depth. Accurately predicting the complex dynamics of tsunami wave run-up in densely populated urban areas is paramount for informing effective evacuation protocols and conducting comprehensive hazard and risk assessments. In pursuit of improving wave run-up prediction capabilities, this study delves into the three-dimensional numerical modelling of wave run-up of non-breaking, long tsunami waves in urbanized areas. Leveraging insights from a physical experiment with pump-driven wave generation and idealized infrastructure, a novel pressure-based wave generation boundary condition is developed. The boundary condition achieves an average of 4.9% accuracy in replicating the water surface elevation from experiments. Additionally, it attains an average 1.5% precision in reproducing flow velocities, furthermore reproducing the spatial flow dynamics accurately. Physical experiment wave run-up is modelled with an average 6.9% deviation for both simulations with and without idealized infrastructure. 63.0% higher non-linearity waves than in the physical experiments are additionally investigated to highlight the boundary conditions capabilities of high non-linearity wave generation, change in run-up reduction for higher non-linearity waves for infrastructure interaction and furthermore in-depth flow field characteristics during tsunami inundation. Finally, the study highlights deviations from analytically calculated wave run-up, emphasizing the necessity for numerical and physical experimental evaluation for both high non-linearity waves and tsunami infrastructure interaction, ultimately fostering both resilience and preparedness against tsunami hazards.

Global tsunami modelling on a spherical multiple-cell grid

A model of shallow water equations (SWEs) on a spherical multiple-cell (SMC) grid of 4-level (2.5-5-10-20 km) spatial resolutions is used to simulate tsunami propagation on global ocean surfaces. The unstructured SMC grid retains rectangular cells of the longitude-latitude grid so that efficient finite-difference schemes could be used. It also supports multi-resolutions like mesh refinement to resolve small islands and coastline details while keeping models compact enough to fit into available computers. Two earthquake-induced tsunami cases are simulated and compared with available observations. Results indicate that the modelled tsunami arrival times agree well with observations while tsunami wave heights are underestimated, particularly the observed runups on remote coastal lands. Possible reasons for this underestimation include the smoothing scheme used to suppress numerical oscillations and the missing of initial kinetic energy input from the earthquakes. Another reason is the limitation of the SWEs to describe coastal bores and breaking waves in coastal waters. A possible tsunami scenario induced by a landslide in the Canary Islands is also simulated to assess its potential impact on Atlantic coastal regions. Model results indicate that this kind of tsunami may cause severe damage to local areas but its effects on far fields, like the UK and American coastal regions are small. As the initial landslide disturbance is overly simplified, this study does not give a true representation of a real landslide tsunami but rather a qualitative assessment of its impact on the Atlantic Ocean. More realistic initial condition and improved model representation of coastal processes are needed for further studies of this possible landslide hazard.

Meteotsunami Impact in Indonesia Due to the Shockwave of the Hunga Tonga Volcanic Eruption on January 15, 2022

This paper presents the impact of a meteotsunami resulting from the shockwave of the underwater volcanic eruption of Hunga Tonga­–Hunga Ha'apai (HTHH) on January 15, 2022.The tsunami was detected in various locations in Indonesia through a network of water level sensors monitored by the Meteorology, Climatology, and Geophysics Agency (BMKG). The tsunami wave heights varied significantly and exhibited a non-linear relationship with the distance from the volcano. The heights of detected tsunami ranged from 2.8 to 22.6 cm, with the highest recorded at the water level sensor south of Java Island. The heights of waves are believed influenced by Proudman resonance in the Indian Ocean waters beside the local amplification effect. The average period of the tsunami waves was approximately 40 minutes, exceeding five days. The tsunami was triggered by the coupling effect between the shockwave with a velocity of 312 m/s and the sea surface. The air pressure anomalies due to the shockwave ranging from 1.2 to 2.2 hPa. Throughout Indonesian waters, this meteotsunami phenomenon did not have a significant impact.

Air effects on solitary waves impinging and overtopping an impermeable seawall

Considering the presence or absence of air, the solitary waves impinging on an impermeable structure were numerically investigated to discuss solitary wave characteristics such as surface elevation, pressure, vorticity, eddy viscosity, and force on structures under different initial conditions. The volume of fluid (VOF) model (Wu, 2004) was employed to simulate solitary waves impinging an impermeable structure. Besides, the LES turbulent module was utilized to capture the turbulent phenomenon generated by wave-structure interactions, particularly after wave breaking. The present model was verified by comparing the simulation results with the experimental data (Hsiao and Lin, 2010). The findings demonstrated that the model more accurately represents tsunami wave behavior compared to simulations that did not account for air, especially in cases where wave breaking occurs prior to overtopping, entraining more air into the water. Detailed comparisons between simulations with and without air presence reveal that simulations excluding air exhibited delayed wave breaking, a more distant breaking point, and the absence of an air pocket behind the seawall. Despite these differences, the simulations showed excellent agreement with the laboratory results. Moreover, it was shown that the presence of air dissipated part of wave energy. Earlier the stage of waves broke, the more air was entrained, making the effects of air on the waves more noticeable. The highest fluid velocity was observed at the breaking point in front of the structure, while the strongest forces were experienced by the structure at the breaking location behind it.

Experimental Investigation on the Drift and Collision of Containers Induced by Tsunami Action on a Wave Absorbing Revetment

&lt;i&gt;This study examined the collision dynamics between tsunami-driven drifting containers and port cranes, prompted by risks from the recent 7.6 magnitude earthquake and tsunami off Noto Peninsula, Japan. Hydraulic experiments were conducted to analyze container drift and collision forces using motion analysis software (DIPP-Motion) and a load cell installed on a crane leg model. The key parameters included the tsunami wave height, container weight (empty and loaded), initial position, and revetment type. The results suggested that higher tsunami wave heights led to more extraordinary inundation, allowing containers to float more efficiently, reducing bottom friction, and increasing drift speed and collision forces. The collision speeds ranged from 1.59 to 2.48 m/s, with collision forces of 45.18 to 77.68 N, representing increases of 6.45 to 15.58 times than no object. Heavier containers required deeper water to float, resulting in lower drift and collision speeds (0.88–0.89 times that of lighter containers). The wave-absorbing revetment caused higher flow velocities, producing collision speeds and forces 1.32–1.48 times greater than the vertical revetment. These findings highlight the importance of considering the tsunami magnitude, container weight, initial position, and revetment type in design, with face-to-face contact conditions crucial for estimating the maximum collision forces and preventing future tsunami damage.&lt;/i&gt;

Computational analysis for fractional model of coupled Whitham-Broer-Kaup equation

In this research paper, we study a semi analytical technique to solve the nonlinear partial differential equations. This technique is good combination of homotopy analysis method with Kharrat-Toma transform. Also, we present the numerical solution of nonlinear fractional coupled Whitham-Broer-Kaup equation using studied technique. The Whitham-Broer-Kaup model is broadly considered to study the tsunami wave dynamics under gravity. The regularized version of Hilfer-Prabhakar fractional derivative is used to model the problem. Some qualitative properties, existence and uniqueness of the considered model and its solution are also discussed.The obtained solutions are presented graphically to show the efficiency of studied technique. Error analysis tables are also given to demonstrate the accuracy of obtained results.

Analytical and dynamical analysis of nonlinear Riemann wave equation in plasma systems

The Riemann wave equation presents appealing nonlinear equations applicable in sea-water and tsunami wave propagation, ion and magneto-sound waves in plasmas, electromagnetic waves in transmission lines, and homogeneous stationary media. This study focuses on deriving soliton solutions in optics and exploring their physical properties. A wave transformation is used to convert a partial differential equation into an ordinary differential equation, from which soliton solutions are obtained using the generalized Riccati equation mapping approach. The solutions encompass various types of solitons, including bright, dark, periodic, and kink solitons. A comparison of solutions from this analytical method enhances the understanding of the nonlinear model’s behavior, with implications in plasma physics, fluid dynamics, optics, and communication technology. Additionally, 2D and 3D graphs illustrate the physical phenomena of the solutions using appropriate constant parameters. The qualitative analysis of the undisturbed planar system involves examining phase portraits in bifurcation theory, followed by introducing an outward force to induce disruption and reveal chaotic phenomena. Chaotic trajectories in the perturbed system are detected through various plots, including 3D, 2D, power spectrum, and chaotic attractor, alongside Lyapunov exponents. Stability analysis under different initial conditions is conducted, and sensitivity assessments are performed using the Runge–Kutta method. The findings are innovative and have not been previously explored for this system, highlighting the reliability, simplicity, and effectiveness of these techniques in analyzing nonlinear models in mathematical physics and engineering.

Possible Indication of the Impact of the Storegga Slide Tsunami on the German North Sea Coast around 8150 cal BP

The Storegga slide tsunami (SST) at ca. 8100 ± 100–250 cal BP is known to be the largest tsunami that affected the North Sea during the entire Holocene. Geological traces of tsunami landfall were discovered along the coasts of Norway, Scotland, England, Denmark, the Faroes and Shetland Islands. So far, the German North Sea coast has been considered as being well protected due to the wide continental shelf and predominant shallow water depths, both assumed to dissipate tsunami wave energy significantly, thus hindering SST propagation dynamics. The objective of our research was to clarify if the SST reached the German Bight and if corresponding sediment markers can be found. Our research was based on the in-depth investigation of a 5 m long section of the research core Garding-2 from Eiderstedt Peninsula near Garding in North Frisia known from a previous study. For this, we newly recovered sediment core Garding-2A at exactly the same coring location as core Garding-2. Additionally, high-resolution Direct Push sensing data were collected to gain undisturbed stratigraphic information. Multi-proxy analyses of sediment material (grain size, geochemical, geochronological and microfaunal data) were carried out to reconstruct palaeoenvironmental and palaeogeographical conditions. We identified a high-energy event layer with sedimentological (e.g., erosional unconformity, rip-up clasts, fining-upward), microfaunal (e.g., strongly mixed foraminiferal assemblage) and other features typical of tsunami influence and identical in age with the SST, dated to ca. 8.15 ka cal BP. The event layer was deposited at or maximum ca. 1–1.5 m below the local contemporary relative sea level and several tens of kilometers inland from the coastline within the palaeo-Eider estuarine system beyond the reach of storm surges. Tsunami facies and geochronological data correspond well with SST signatures identified on the nearby island of Rømø. SST candidate deposits identified at Garding represent the southernmost indications of this event in the southeastern North Sea. They give evidence, for the first time, of high-energy tsunami landfall along the German North Sea coast and tsunami impact related to the Storegga slide. SST deposits seem to have been subsequently reworked and redeposited over centuries until the site was affected by the Holocene marine transgression around 7 ka cal BP (7.3–6.5 ka cal BP). Moreover, the transgression initiated energetically and ecologically stable shallow marine conditions within an Eider-related tidal channel, lasting several millennia. It is suggested that the SST was not essentially weakened across the shallow continental shelf of the North Sea, but rather caused tsunami run-up of several meters (Rømø Island) or largely intruded estuarine systems tens of kilometers inland (North Frisia, this study). We, therefore, assume that the southern North Sea coast was generally affected by the SST but sedimentary signals have not yet been identified or have been misinterpreted. Our findings suggest that the German North Sea coast is not protected from tsunami events, as assumed so far, but that tsunamis are also a phenomenon in this region.

3D anatomy of the Cretaceous–Paleogene age Nadir Crater

The Nadir Crater offshore West Africa is a recently proposed near K-Pg impact structure identified on 2D seismic. Here we present 3D seismic data that image this crater in exceptional detail, unique for any such structure, which demonstrates beyond reasonable doubt that the crater-forming mechanism was a hypervelocity impact. Seismic mapping reveals a near-circular crater rim of 9.2 km and an outer brim of ~23 km diameter defined by concentric normal faults. An extended damage zone is evident across the region, well beyond the perceived limit of subsurface deformation for impact craters, except in a ‘sheltered zone’ to the east. The paleo-seabed shows evidence for widespread liquefaction because of seismic shaking, and scars and gullies formed by tsunami wave propagation and resurge. Deformation within the ~425 m high stratigraphic uplift and annular moat allows us to reconstruct the evolution of the crater, with radial thrusts at the periphery of the uplift suggesting a low-angle impact from the east. Structural relationships are used to reconstruct the deformation processes during the crater modification stage, with the central uplift forming first, followed by centripetal flow of surrounding sediments into the evacuated crater floor in the seconds to minutes after impact.

GIS Modelling for Prediction of Tsunami Inundation Areas in Coastal Areas of Malang Regency

Abstract This study utilizes Geographic Information System (GIS) modeling to predict potential tsunami inundation areas along the coastal regions of Malang Regency. The capabilities of GIS in this research integrate regional topography and land use data to model tsunami inundation scenarios accurately. The topographic modeling process employs Alos Palsar Digital Elevation Model (DEM) data, which provides detailed elevation information critical for assessing inundation risks. Three altitude scenarios 10 meters, 15 meters, and 20 meters are analyzed to gauge the extent and height of potential tsunami waves. In the 10-meter scenario, the areas most susceptible to inundation include Donomulyo, Bantur, and Gedangan, highlighting these zones as critical areas for immediate attention. As the scenario elevation increases to 15 meters, Gedangan, and Sumbermanjing Wetan emerge as the most vulnerable regions, suggesting a broader risk as tsunami wave heights escalate. The 20-meter scenario further accentuates the vulnerability of Gedangan and Sumbermanjing Wetan Districts, which exhibit the widest potential inundation areas. By identifying the most at-risk areas, this research provides valuable insights for policymakers and planners to develop targeted strategies to mitigate the impact of tsunamis. Advanced GIS modeling is a crucial tool in enhancing the preparedness and resilience of coastal communities against tsunami hazards.

Physical Modeling of Tsunamis Generated by Submarine Volcanic Eruptions

AbstractSubmarine volcanic eruptions can induce major local and regional tsunami hazards through varied source mechanisms. Large‐scale experiments of tsunamis generated by submarine volcanic eruptions are conducted to study the cylindrical wave generation and propagation in a three‐dimensional wave basin. A unique volcanic tsunami generator (VTG) was deployed at the bottom of the wave basin to generate volcanic tsunamis with repeatable and controlled source parameters. The physical modeling is based on the generalized Froude number defined with the VTG velocity and the near source water depth. The pneumatically driven vertical stroke motion generates leading elevation waves in the wave basin. The tsunami waves generated by the VTG are measured with a wave gauge array. The wave maker performance is characterized by the dimensionless leading wave amplitudes and periods. The experimental data show the variations of the leading wave amplitude, period, and celerity along the radial propagation distance. The generated cylindrical waves belong to the weakly nonlinear wave regime in the near field with decaying wave amplitude along radial propagation. The attenuation rate of the leading wave exceeds the range from the linear wave theory in runs with higher Froude numbers. The dimensionless leading wave period increases with the dimensionless propagation distance due to the dispersion relation. Empirical equations for the characteristic wave parameters such as amplitudes and periods are derived. The experimental results contribute to the understanding of volcanic tsunami generation processes and may serve rapid volcanic tsunami hazard assessments as well as the advancement and validation of numerical models.

Compressible ocean waves generated by sudden seabed rise near a step-type topography

A typical tsunami generation occurs through submarine earthquakes leading to large volume displacement. The corresponding mathematical problem involves modeling surface water waves generated by an arbitrary temporal motion of the ocean floor. The propagation of tsunami wave and the subsequent scattering from a sudden drop in bathymetry away from the ground motion is studied following linearized water wave theory and a weakly compressible ocean, including static oceanic background compression. The Fourier transformation and eigenfunction expansion techniques are employed to find the surface displacement and pressure profiles by leveraging appropriate matching conditions between regions of different depths. A novel energy balance relationship is derived by considering both the pure-gravity and acoustic-gravity modes. The model is validated in the limit that the depth difference approaches zero, showing a vanishing reflection contribution from the depth change. An efficient numerical code is developed that accurately captures the contribution of the cutoff frequencies of acoustic-gravity modes. Apart from the time-domain propagation of tsunami waves away from the origin, standing wave formations are observed within the shallow region, supported by significantly large pressure fluctuations in time. These standing waves or, equivalently, the pressure fluctuations sustain longer for larger ocean depth. The increase in tsunami speed in the deeper region is readily visible in the time-domain simulations. A three-dimensional axisymmetric solution is also developed, and results show a more gradual sloping tsunami wavefront compared to the equivalent two-dimensional solution for shallower depths. Animation movies corresponding to the two- and three-dimensional surface profiles are provided for better visualization.

Source Geometry and Rupture Characteristics of the 20 February 2023 Mw 6.4 Hatay (Türkiye) Earthquake at Southwest Edge of the East Anatolian Fault

AbstractFollowing the catastrophic 6 February 2023 Mw 7.8 and Mw 7.6 Kahramanmaraş earthquakes in the East Anatolian Fault Zone (EAFZ; southeast Türkiye), numerous aftershocks occurred along the major branches of this left‐lateral shear zone. The spatio‐temporal distribution of the earthquakes implied the stress‐triggering effects of co‐seismic ruptures on closely connected fault segments over large distances. On the 20 February 2023 two earthquakes with Mw 6.4 and Mw 5.2 struck Hatay (Türkiye) located near the Samandağ‐Antakya segment of the EAFZ. To understand the rupture evolution of these earthquakes, we first re‐located the aftershock sequence that occurred over a 3‐month period in the Hatay‐Syria region. A normal faulting mechanism with a significant amount of left‐lateral strike‐slip component at a shallow focal depth of 12 km was estimated for the 2023 Mw 6.4 earthquake from the inversion of seismological data. Our slip models describe a relatively simple and unilateral rupture propagation along about 36 km‐long active segments of the EAFZ. The co‐seismic horizontal displacements inferred from the Global Navigation Satellite System data are compatible with the oblique slip kinematics. Furthermore, we suggest that this earthquake did not produce notable tsunami waves on the adjacent coasts since the rupture plane did not extend to the seafloor of the Eastern Mediterranean with substantial amount of vertical displacement. We reckon that a future large earthquake (Mw ≥ 7.0) in the Hatay‐Syria region where increased stress was transferred to the fault segments of the EAFZ and the Dead Sea Fault Zone (DSFZ) after the 2023 earthquakes will be a probable source of tsunami at the coastal plains of the Eastern Mediterranean Sea region.

Observations of Tsunami Waves on the Pacific Coast of Russia Originating from the Hunga Tonga-Hunga Ha'apai Volcanic Eruption on January 15, 2022

The Hunga Tonga-Hunga Ha´apai volcanic eruption on January 15, 2022 generated a tsunami that affected the entire Pacific Ocean. Tsunami from the event have been generated both by incoming waves from the source area, with a long-wave speed in the ocean of ~ 200–220 m/s, and by an atmospheric wave propagating at a sound speed ~315 m/s. Such a dual source mechanism created a serious problem and was a real challenge for the Pacific tsunami warning services. The work of the Russian Tsunami Warning Service (Yuzhno-Sakhalinsk) during this event is considered in detail. The tsunami was clearly recorded on the coasts of the Northwest Pacific and in the adjacent marginal seas, including the Sea of Japan, the Sea of Okhotsk and the Bering Sea. We examined high-resolution records (1-min sampling) of 20 tide gauges and 8 air pressure stations in this region for the period of January 14–17, 2022. On the Russian coast, the highest waves, with a trough-to-crest wave height of 1.3 m, were recorded at Malokurilskoe (Shikotan Island) and Vodopadnaya (the southeastern coast of Kamchatka). Using numerical simulation and data analysis methods, we were able to separate the oceanic “gravity” tsunami waves from propagating atmospheric pressure waves. In general, we found that on the outer (oceanic) coasts and the southern coast of the Sea of Okhotsk, oceanic tsunami waves prevailed, while on the coast of the Sea of Japan, oceanic and atmospheric tsunami waves had similar heights.

Development and Application of a Novel Tsunami Monitoring System Based on Submerged Mooring.

Real-time data transmission and reliable operation are essential for a tsunami monitoring system to provide effective data. In this study, a novel real-time tsunami monitoring system is designed based on a submersible mooring system. This system is equipped with a data acquisition and tsunami wave identification algorithm, which can collect the measured data of the pressure sensor and detect a tsunami wave in real time. It adopts the combination design of underwater inductive coupling transmission and a redundant BeiDou communication device on the water surface to ensure the reliability of real-time data transmission. Compared with traditional tsunami monitoring buoys, it has the advantages of reliable communication, good concealment, high security, and convenient deployment, recovery, and maintenance. The results of laboratory and sea tests show that the system has high reliability of data transmission, stable overall operation of the system, and good application prospects in the field of real-time tsunami monitoring and early warning.