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High‐resolution Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension is used to simulate the responses to the Hunga‐Tonga volcano eruption on 15 January 2022. Global propagation of the Lamb wave L’0 and L’1 pseudomodes are reproduced in the simulation, with the exponential growth of wave amplitudes with altitudes. The wavefront is vertical up to the lower thermosphere, and tilts outward above. These features are consistent with theoretical results. With simulated surface pressure perturbation agreeing with observations (∼100–250 Pa), thermospheric wind perturbations over 100 ms−1 are comparable with reported satellite and ground‐based observations. Traveling ionospheric disturbances in the total electron contents from the simulation show good agreement with observations, including magnitude and propagating speed and evidence of conjugacy in the first 1–2 hr after eruption. Conjugacy in E × B drift, on the other hand, is more persistent. Plain Language Summary As one of the most powerful volcano eruptions on record, the Hunga Tonga‐Hunga Ha'apai Volcano produces waves that ripple through the atmosphere and near‐space environment. These wave signals have been recorded by observations from instruments on the ground and from satellites, and they propagate around the Earth multiple times. This event provides a rare opportunity to study the strong and direct connection of the whole atmosphere system. The challenge is for a model to be able to represent the key processes in the whole atmosphere system and to have sufficient spatial and temporal fidelity to gain a realistic global picture of the event. This is achieved in the study by using the high‐resolution Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension. The model is able to simulate the global propagation of the waves, and the model results compare favorably with observations from the surface to the thermosphere and ionosphere. Key Points High‐resolution Whole Atmosphere Community Climate Model with thermosphere/ionosphere extension simulation of Hunga eruption shows whole atmosphere responses Simulated wave amplitude growth and phase structure are consistent with the theoretical prediction Simulation results are comparable with thermospheric and ionospheric observations

The global 3‐dimensional structure of the concentric traveling ionospheric disturbances (CTIDs) triggered by 2022 Tonga volcano was reconstructed by using the 3‐dimensional computerized ionospheric tomography (3DCIT) technique and extensive global navigation satellite system (GNSS) observations. This study provides the first estimation of the CTIDs vertical wavelengths, ∼736 km, which was much larger than the gravity wave (GW) vertical wavelength, 240–400 km, estimated using ICON neutral wind observations. Notable trend with the variation of azimuth was also found in horizontal speeds at 200 and 500 km altitudes and differences between them. These results imply that (a) the global propagation of Lamb waves determined the arrival time of local ionospheric disturbances, and (b) the arriving Lamb waves caused vertical atmospheric perturbations that are not typical of GWs, resulting in local thermospheric horizontal wave propagation which is faster than the Lamb wave propagation at lower altitudes. Plain Language Summary After the 2022 Tonga volcano eruption, atmospheric waves including Lamb waves, gravity waves, acoustic waves were triggered in the lower atmosphere (below 100 km altitude) and the concentric traveling ionospheric disturbances (CTIDs) were also observed above 100 km altitude. However, since these atmospheric waves can have similar horizontal wavelength and speeds, it is challenging to determine the driver of the ionospheric disturbances using 2D GNSS Total Electron Content measurements or satellite in‐situ observations. In this study, the GNSS ionospheric tomography technique is employed to reconstruct 3D structures in different regions. The horizontal speeds of CTIDs showed different features at different altitudes and azimuths. In addition, the gravity vertical wavelength estimated using ICON neutral wind observation is much smaller than the tomography derived vertical wavelength. At the same time, most of the CTIDs arrival times coincided with the speed of the Lamb waves. Key Points The horizontal speed of the ionospheric disturbances showed a prominent dependence on altitude and azimuth The ionospheric disturbances had a much larger vertical wavelength than gravity waves, and their arrival times coincided with Lamb waves Lamb waves induced local thermospheric horizontal wave propagation that is faster than their propagation at lower altitudes

In 2022, the Hunga volcano eruption in Tonga generated atmospheric pressure waves that propagated globally and produced tsunamis in all the world's oceans. The largest pressure wave, with an amplitude of several hundred pascals, is the Lamb wave. Standard Lamb wave models, incorporating the sound‐speed as a function of temperature, satisfactorily explain observations in the near‐field but not in the far‐field. We show that an augmented Lamb wave model that includes the effects of wind and topography accurately reproduces the wavefronts observed by satellites and barometers, including those close to the antipode. Winds, first suggested to explain the travel times of Lamb waves from Krakatau in 1883, are now shown to also play a major role in shaping their waveforms; temperature and topography play smaller, but still detectable, roles. Our augmented model provides a significant advance for the development of early warning and hazard assessments for the meteotsunamis these waves produce. Plain Language Summary The January 2022 explosive eruption of the Hunga volcano in Tonga produced a pressure wave (of a type known as a Lamb wave) in the atmosphere, which was detected worldwide. This wave circled the Earth more than once, and generated tsunami in unexpected times and places. We have derived a mathematical description that allows us to quickly and accurately model the observations of this atmospheric wave. The description includes the effects of winds, temperature, and topography. The wave modeled using this description reproduces satellite and ground observations much better than simpler models, notably the complex pattern of the wave near the antipode of the eruption. Our model clearly identifies global winds as the crucial influence on global‐scale Lamb‐wave propagation, and provides modeling tools for possible future occurrences of such waves and the global tsunamis created by them. Key Points A augmented model is proposed to simulate the propagation of planetary scale Lamb waves, incorporating wind, temperature and topography Winds play a primary role shaping Lamb waves in the far field, especially near the antipode of the source The augmented Lamb wave model will help better assess far‐field volcanic tsunami hazards

The 15 January 2022 eruption of the Hunga volcano generated a Lamb wave, a global atmospheric pressure perturbation which propagates purely horizontally at the speed of sound. Far‐field observations of the daytime passage of the Lamb wave by the Geostationary Operational Environmental Satellite‐R (GOES‐R) series, revealed unexpected, synchronized variations in the solar reflectance of low‐level liquid clouds, the most prominent of which is a transient darkening accompanying the overpressure peak. We hypothesize that this darkening is mostly caused by the rapid thermodynamic adjustment of the cloudy environment to the slight, but spatially coherent, warming introduced by the pressure pulse. The corresponding reduction in relative humidity leads to the shrinkage and evaporation of small cloud droplets and hygroscopic particles in the halo region, which, in turn, temporarily reduces the optical thickness of the cloudy column.

A large eruption occurred on Jan. 15, 2022, at the submarine volcano Hunga Tonga-Hunga Ha’apai, southern Pacific, and the atmospheric Lamb wave was observed to have traveled round the Earth multiple times with a speed of ~ 0.3 km/s. Here, I compare their ionospheric and atmospheric signatures using data from dense arrays of barometers and GNSS stations in Japan. I confirmed that the ionospheric disturbances passed over Japan at least four times, first from SE to NW, then from NW to SE, again from SE to NW, and finally from NW to SE. The propagation velocity of the ionospheric disturbances was as fast as the atmospheric Lamb wave, suggesting their origin as upward energy leakage from the troposphere. The first passage of the ionospheric disturbance started prior to the arrival of the Lamb pulse, but its physical mechanism is yet to be explored. Unlike the barometric records, waveforms and amplitudes of ionospheric disturbances exhibit large diversity along the wavefront, suggesting their turbulent nature.

The resonant behavior of one-way Lamb and SH (shear horizontal) mixing method in composite laminates with transverse-isotropic quadratic nonlinearity is investigated through numerical simulations in this paper. Different from previous studies, the composite constitutive model is combined from orthotropic elasticity and transverse-isotropic quadratic nonlinearity, which is implemented by ABAQUS/VUMAT subroutine. When two fundamental waves ( S 0 -mode Lamb waves and SH 0 waves) mix in composite laminates with quadratic nonlinearity, the resonant SH 0 waves can be generated with the resonance condition ω S 0 / ω SH 0 = 2 κ /( κ + 1). Meanwhile, the relationships between the acoustic nonlinear parameter (ANP) and damage degree, fundamental frequency, frequency deviation, propagation distance are also investigated. Moreover, the method of locating the damage region in composite laminates is proposed and verified by using the resonant wave time-domain signal.

The explosive 2022 Tonga submarine volcanic eruption produced a globally propagated atmospheric disturbance. A leading Lamb wave pulse was recorded as a pressure pulse worldwide. A weather‐station network in Japan recorded the pressure pulse together with temperature and wind conditions during the passage of the pulse. Individual temperature and wind records indicate little simultaneous change. However, after alignment of records at the time of pressure pulse arrivals and stacking, clear temperature and wind changes synchronized with the pressure change are evident. Assuming Lamb wave propagation, the synthesized temperature and wind changes from the pressure record show a good match with the observed waveforms. The observed wind speed and pressure change of the Lamb pulse yielded a total energy transported by the pulse of 4.2 × 1016 J. Plain Language Summary Atmospheric disturbance caused by the violent 2022 Tonga volcanic eruption was recorded by multiple types of sensors on the ground. The leading pressure signals, of about 20 min duration and about 2 hPa amplitude, were observed in a nationwide weather network in Japan as an anomaly that stands out from the background atmospheric pressure trend. Other meteorological sensors such as temperature and wind components were also in operation, but expected changes are on the order of 0.15 K and 0.5 m/s over the 20 min signal duration, too small to be detected in individual records. Using a pressure signal as a time mark for data alignment, we averaged all temperature and wind components parallel to the direction from Tonga toward Japan recorded by the network. Such averaging steps greatly reduced the spatially incoherent background noise and enhanced the signals coherent with the arrival of the pressure pulse. The resultant temperature and wind changes are comparable to the theoretically predicted ones. The measured temporal changes of atmospheric pressure and air flow enable direct estimation of the energy flow transported by the pressure pulse. The estimated total energy transported by the pressure pulse is between (3.8–4.6) ×$\\times $  1016 J. Key Points Stacking nationwide weather network records reveals temporal changes in temperature and wind flow synchronized with the Lamb pressure pulse Observed temporal variations are close to the adiabatic air compression and Lamb wave flow models expected from the pressure pulse Analysis of observed wind speed and pressure changes reveals that the total energy transported by the Lamb pulse was 4.2 × 1016 J

Thermal tides are global oscillations driven by periodic solar heating that strongly influence circulation and vertical coupling in the Martian atmosphere. Previous studies have focused on the first and second migrating harmonics, while recent work has revealed higher‐frequency harmonics in surface pressure records. However, these detections are limited to single locations, and spacecraft observations have only confirmed global structure up to the third harmonic. Here, we present the first planetary‐scale characterization of migrating thermal tides up to the eighth harmonic as observed in remotely sensed temperature observations from the Emirates Mars Mission, sampling the lower atmosphere, and surface pressure measurements from the Curiosity and Perseverance landers. We examine the latitudinal and seasonal structure and show that high‐frequency migrating tides have deep vertical structure with little phase variation with height, suggestive of near‐resonant Lamb wave structure. Nearly identical seasonal amplitude‐phase evolution across the longitudinally separated landers, indicate dominance of migrating tides.

Tsunamis generated by the Hunga Tonga–Hunga Ha’apai volcanic eruption on January 15, 2022 were recorded on ocean bottom pressure and tide gauges around the Pacific Ocean, earlier than the expected arrival times calculated by tsunami propagation speed. Atmospheric waves from the eruption were also recorded globally with propagation speeds of ~ 310 m/s (Lamb wave) and 200–250 m/s (Pekeris wave). Previous studies have suggested that these propagating atmospheric waves caused at least the initial part of the observed tsunami. We simulated the tsunamis generated by the propagation of the Lamb and Pekeris waves by adding concentric atmospheric pressure changes. The concentric sources are parameterized by their propagation speeds, initial atmospheric wave amplitudes that decay with the distance, and a rise time. For the Lamb wave, inversions of the observed tsunami waveforms at 14 U.S. and nine New Zealand DART stations indicate the start of the positive rise at 4:16 UTC, the peak amplitude of 383 hPa, and the propagation speed of 310 m/s, assuming a rise time of 10 min. The later phases of the observed tsunami waveforms can be better reproduced by adding another propagating concentric wave (Pekeris wave) with a negative amplitude (− 50 hPa) and propagation speeds of 200–250 m/s. The DART records around the Pacific indicate that the Pekeris wave speed is faster toward the northwest and slightly slower toward the northeast. The synthetic waveforms roughly reproduced the far-field tsunami waveforms recorded at tide gauge stations, including the later phases, suggesting that the large amplitude in the later phase may be due to the coupling of the Pekeris wave and the tsunami, as well as resonance around tide gauge stations.

On January 15, 2022, we observed various unusual atmospheric wave events over South America: Atmospheric pressure waves (Lamb mode) around 12:30 to 17:30 UT, tsunamis along the Chilean coast at around 17:00 to 19:00 UT, and ionospheric disturbances between 11:30 and 20:00 UT. We understand that these events were generated by the Tonga volcanic eruption that occurred at (20.55°S, 175.39°W) in South Pacific Ocean at 04:15 UT. Several traveling ionospheric disturbances (TIDs), the horizontal wavelengths of 330 to 1174 km and the phase speed of 275–544 m/s were observed before and after the Lamb wave passed over the continent and the arrival of the tsunami on the Chile coast. The observed TID characteristics suggest us that these waves might be generated by the two atmospheric events, Lamb wave and gravity waves induced by the tsunamis. This is the first time to report the signature of ionospheric disturbances over the South American continent generated by the huge volcanic eruption.Plain Language SummaryA huge volcanic eruption occurred at the volcano Hunga Tonga Hunga Ha’apai (20.55°S, 175.39°W), one of the islands of the Tonga archipelago in the South Pacific Ocean, on 15 January 2022, at 04:15 UT (Universal Time). The eruption released a huge amount of thermal energy into the atmosphere that reached up to ~ 50 km altitude. Such an explosive release of thermal energy produced atmospheric pressure waves, acoustic waves, and internal gravity waves in the lower atmosphere propagating horizontally and vertically up to the ionosphere (above 200 km altitude). The present work, as the first time, reports signatures of the ionospheric disturbances caused by the tsunami and atmospheric pressure waves over the South American continent.