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The Hunga Tonga-Hunga Ha'apai volcano eruption of January 15th 2022 generated a global atmospheric and oceanic response that was recorded by an unprecedented amount of sensors. The eruption caused an atmospheric perturbation that travelled as a Lamb wave surrounding the Earth at least 3 times, and was recorded by hundreds of barographs worldwide. The atmospheric wave showed complex patterns of amplitude and spectral energy content, although most of the energy was concentrated in the band (2-120 min). Simultaneously to each passage of the atmospheric wave and after, significant Sea Level Oscillations (SLOs) in the tsunami frequency band were recorded by tide gauges located all around the globe, in what it can be referred to as a global meteotsunami. The amplitude and dominant frequency of the recorded SLOs showed a high spatial heterogeneity. Our point is that the geometry of continental shelves and harbours acted as tuners for the surface waves generated by the atmospheric disturbance at open sea, amplifying the signal at the eigenmodes of each shelf and harbour.

Numerical simulation results for the atmospheric Lamb waves generated by the Hunga-Tonga volcano explosion on January 15th 2022.

On 15 January 2022, around 4:30 UTC the eruption of the Hunga-Tonga volcano, in the South Pacific Ocean, generated a violent underwater explosion. In addition to tsunami waves that affected the Pacific coasts, the eruption created atmospheric pressure disturbances that spread out in the form of Lamb waves. The associated atmospheric pressure oscillations were detected in high-frequency in-situ observations all over the globe. Here we take advantage of the similarities in the propagation and characteristics between atmospheric Lamb waves and long ocean waves and we use a 2DH ocean numerical model to simulate the phenomenon. We compare the outputs of the numerical simulation with in-situ atmospheric pressure records and with remote satellite observations. The signal in the model matches the observed atmospheric pressure perturbations and reveals an excellent agreement in the wave arrival time between model and observations at hundreds of locations at different distances from the origin.

Pure and Applied Geophysics (PAGEOPH) is one of the leading journals in the field of geophysics. The first issue was published in 1939; thus, the journal is celebrating its 80th anniversary in 2018. The aim of this paper is to provide a complete lifetime overview of the academic structure of the journal using bibliometric indicators. This analysis includes key factors such as the most cited articles, leading authors, originating institutions and countries, publication and citation structures, and the most commonly used keywords. The bibliometric data used to conduct this analysis comes from the Scopus database. Additionally, the visualization of similarities (VOS)viewer software is used to create a graphic map of some of the bibliometric results. The graphical analysis uses co-citation, bibliographic coupling and co-occurrence of keywords. The results indicate that PAGEOPH is a leading journal in the areas in which it is indexed, with publications from a wide range of authors, institutions, and countries around the world.

Mesoscale eddies are a key oceanic feature relevant to the transport of water properties and biological material. These structures, through their surface signature, have been characterized and widely investigated using sea level anomaly (SLA) maps retrieved from satellite altimetry observations. Gridded SLA fields are routinely computed combining SLA data along satellite tracks with an optimal interpolation algorithm using a selected set of parameters. These are crucial because they define and constrain the temporal and spatial scales of the structures resolved. Here, we investigate the impact of the choice of the interpolation parameters in global and in the Mediterranean SLA products. Our findings demonstrate that the number of eddies detected in SLA maps over the Mediterranean Sea regional products is significantly larger along the satellite tracks than between the tracks, irrespective of the number of satellites used to produce the gridded maps, of the time period considered and of the eddy size. We also show that this is not the case of the global SLA product. We attribute the anomalously high number of eddies detected along the tracks in the regional products to the correlation scales of the optimal interpolation algorithm, which are different from those in the global product due to a smaller Rossby radius of the Mediterranean structures. Among these, we find that the time correlation scale is more restrictive than the spatial one.

A climate synoptic meteotsunami index has been constructed using synoptic variables for the Balearic Islands. The index allows for the very first assessment of atmospherically driven intense sea level oscillations at the tsunami timescale (<2 hr) in future climates. The index has been computed using outputs from evaluation, historical, and three scenario MED-11_CNRM Med-CORDEX regional atmospheric climate runs. The reliability of the index has been verified against reanalysis simulations and on documented meteotsunami events. No significant changes in the index are projected under RCP2.6 and RCP4.5 scenarios, while the yearly number of days with meteotsunamis is expected to increase by 34% under the RCP8.5 scenario by the year 2100. This increase will dominantly occur during the summer season (May–August), being contemporaneous with maximum index values. The presented results are relevant for assessment of sea level extremes worldwide, since high-frequency sea level oscillations may contribute up to 40% of the total range. Plain Language Summary The study aims to develop the proxy methodology to be used for assessment of meteotsunamis—atmospherically driven waves in a tsunami frequency band—in the future climate, as the present climate models are far from reproduction of processes on a minute and a kilometer scale. The proxy estimates are based on connecting synoptic parameters and patterns to the high-frequency sea level observations. The methodology is successfully verified for Ciutadella harbor, a known hot spot for meteotsunamis, on state-of-the-art reanalysis data. It seems that meteotsunamis are likely not to increase in all but business-as-usual (RCP8.5) climate scenarios, where the increase is matching the season when meteotsunami reach their maximum (spring–summer). The methodology might be useful for assessing meteotsunami hazard in future climates, while being applied at places where meteotsunamis are driven dominantly by a single atmospheric process. Glo

A hydrodynamic comparison between two zones of fishing interest, one located to the north and the other to the south of Mallorca Island (Balearic Islands, Western Mediterranean) was done. The comparison was conducted using the data from two moorings, one placed in the middle of the Balearic Current, in the Balearic subbasin (herein, Sóller) and the other in the Mallorca Channel, near the Algerian subbasin (called Cabrera). The instruments moored, continuously recorded the temperature, salinity and currents at different depths, for over 15. months. The data analysis suggests that Sóller is hydrodynamically more active than Cabrera, at least during the time of recording the measurements. The mean currents were higher at Sóller than at Cabrera at all depths, also showing greater maximum speeds and variability. In addition, the presence of more mesoscale eddies in Sóller became evident from the altimetry data. These eddies were not only significantly more energetic near the surface, they also generally reached to greater depths, affecting the velocities of the seabed currents. Subsequent to each significant eddy episode, strong changes in temperature and/or salinity were observed, along the entire water column. Spectral analysis revealed the presence of high frequency oscillations with periods of a few hours. One energy peak, with a period around 3.7. h, was observed at both locations, probably related to trapped waves around Mallorca or the Balearic Islands, while others (3. h and 2. h) were reflected only in Sóller, suggesting they could be associated with some standing resonance waves between the Iberian Peninsula and Mallorca. © 2014 Elsevier B.V.

Settled material recorded by two near bottom sediment traps deployed from November 2009 to February 2011 at northern (Sóller) and southern (Cabrera) slopes of Mallorca Island (Western Mediterranean) is studied with the aim of discerning their possible origin. The total settled particulate mass fluxes (TMF) at Sóller station were found to be, on average, 2.8 times greater than at Cabrera location during the deployment period, although both time series had a similar temporal evolution. It is suggested that wind episodes affecting the entire area were the common forcing, causing a primary production enhancement and being responsible of the similar temporal behavior. The greater sediment amounts collected in Sóller are explained on the basis of two physical mechanisms: 1) a number of successive eddies generated by instabilities of the Balearic Current that are regularly observed on satellite images, some of which have been reported to reach the seabed, thus increasing near bottom velocities and causing sediment resuspension. And 2) bottom trapped waves that are evidenced from a wavelet analysis in Sóller which could affect the TFM by enhancing sediment resuspension or advecting material from the surrounding areas. © 2014 Elsevier B.V.

High frequency sea level oscillations at Wells Harbor (Maine, Northeastern US), with periods in the range of several tens of minutes, display a tidally modulated response. During low tides, these sea level oscillations reach amplitudes of 10–20 cm, while during high tides they are significantly smaller. Wells Harbor is located in a low lying area with a tidal range of about 2 m and is connected to the open ocean through a narrow channel. Thus, the extent and depth of the bay significantly vary over a tidal cycle. This changing geometry determines both the resonant periods and the amplification factor of the bay. Numerical results confirm the link between observed variability and these specific topographic features. Results imply that when exceptionally energetic long waves reach the Wells Harbor entrance (as in the case of a tsunami or meteotsunami) the expected response will be significantly stronger during low tide than during high tide. Although mean sea level would be lower in the former case, the currents inside the bay would be stronger and potentially more dangerous. This tidally modulated response could be extrapolated to other sites with similar topographic characteristics. © 2014, Springer Science+Business Media Dordrecht.

Monthly catches per unit of effort (CPUE) of adult red shrimp (. Aristeus antennatus), reported in the deep water bottom trawl fishery developed on the Sóller fishing ground off northern Mallorca (Western Mediterranean), and the mean ocean surface vorticity in the surrounding areas are compared between 2000 and 2010. A good correlation is found between the rises in the surrounding surface vorticity and the drops in the CPUE of the adult red shrimp. This correlation could be explained by assuming that most of the surface vorticity episodes could reach the bottom, increasing the seabed velocities and producing sediment resuspension, which could affect the near bottom water turbidity. A. antennatus would respond to this increased turbidity disappearing from the fishing grounds, probably moving downwards to the deeper waters. This massive displacement of red shrimp specimens away from the fishing grounds would consequently decrease their accessibility to fishing exploitation. Similar although more intense responses have been observed during the downslope shelf dense water current episodes that occurred in a submarine canyon, northeast of the Iberian peninsula. The proposed mechanism suggesting how the surface vorticity observed can affect the bottom sediments is investigated using a year-long moored near-bottom current meter and a sediment trap moored near the fishing grounds.The relationship between vorticity and catches is also explored for fish species (. Galeus melastomus, Micromesistius poutassou, Phycis blennoides) and other crustacean (. Geryon longipes and Nephrops norvegicus), considered as by-catch of the deep water fishery in the area. Results appear to support the suggestion that the water turbidity generated by the vorticity episodes is significant enough to affect the dynamics of the demersal species. © 2013 Elsevier B.V.