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The role of resonance has been long recognized as a relevant aspect in controlling the duration and other inundation metrics of tsunami response. However, whether their site-specific behavior is controlled by the source or the morphology is challenging to be determined owing to several reasons. First, in situ data to carry out the characterization can be only obtained during tsunami events, and it is usually spatially sparse, thereby limiting generalization. Moreover, distinguishing between source and bathymetric control is possible in these cases even though both signals are intermingled, but whether the resulting amplification will be similar for other events is debatable. Alternatively, analytical or numerical methods can identify multiple modes dominated by the bathymetry. However, distinguishing which ones would dominate the actual response remains a challenge because earthquake source characteristics are usually absent.In this work, we take advantage of using a large number of stochastic earthquake simulations to drive a NLSWE numerical model to identify response trends on a set of different bays in Central Chile. We couple these results with a free oscillation model and historical data to validate some cases. Results show that bays can be classified as being bathymetry-controlled, source-controlled, or a mixture of both, depending on how consistent their response is when magnitudes and rupture distributions are varied. Such characterization could help in understanding site-specific hazards, as a first step to mitigation., The 28th IUGG General Assembly (IUGG2023) (Berlin 2023)

The intertidal beach profile provides coastal engineers and managers with a good indication of the current state of a sandy coastline, however regular beach profile measurements are time consuming and expensive to obtain using conventional surveying methods. The potential to reconstruct the intertidal beach profile from measurements of reflected waves is tested here using three field datasets covering a different range of hydro-morphological conditions from dissipative, to reflective. The swash is found to behave as a low-pass filter on reflected waves, with a cut-off frequency that primarily depends on the swash slope. An agreement is found between video-derived swash spectrum saturation tail and the shortest reflected waves, computed from deep water directional wave measurements. By integrating this swash slope over a tidal cycle, the shape of the intertidal beach profile can be reconstructed. Our results clearly show the potential of such method to estimate complex intertidal beach profile, such as double-slope beaches.

Reflected waves account for a significant part of the nearshore energy budget and influence incoming waves, nearshore circulation and sediment transport. The use of swash parameters to estimate wave reflection is investigated at three different beaches ranging from highly reflective to dissipative. It is observed that it is essential to account for swash processes when estimating reflection, in particular at intermediate and reflective beaches with a steep beachface. Our results show that runup asymmetry in uprush/backwash can be used as a proxy for dissipation in the swash zone: larger asymmetry values indicating greater dissipation. In our dataset, a reflection predictor based on runup asymmetry has better skill in comparison to empirical predictors based on surf similarity, because runup is a process that integrates both surf and swash zone wave transformation. Runup asymmetry behaves as a swash similarity parameter and reflects an equilibrium between swash period, slope and dissipation.

Resumen Se realizó un estudio descriptivo tipo reporte de caso de un paciente valorado por el servicio de gastroenterología en la Clínica Nuestra en la ciudad de Cali, por sospecha de sangrado digestivo oculto cuyos estudios previos no habían mostrado causa de sangrado. Se realizó videocápsula endoscópica (MiroCam®) con un hallazgo positivo de lesión en el intestino delgado. Se llevó a enteroscopia en Clínica Farallones de la Ciudad de Cali con enteroscopio Olympus 180 Q que confirmó el hallazgo. Ulteriormente, se llevó a cirugía, en la que se confirmó el diagnóstico. Los datos y las fotografías se obtuvieron en bases de datos de los servicios de endoscopia y las fotos de patología se obtuvieron del registro del médico patólogo. Finalmente, se realizó una búsqueda en PubMed sobre literatura existente de historia clínica y reportes de casos similares. Abstract This is a descriptive study based on the case report of a patient suspected of occult gastrointestinal bleeding who was evaluated by the gastroenterology service in Clínica Nuestra in Cali. Previous studies had not shown cause of bleeding. Video endoscopy (Mirocam) found a lesion in the small intestine. Enteroscopy at performed at Clínica Farallones in Cali with an Olympus 180 Q enteroscope confirmed the finding. Surgery further confirmed the diagnosis. Data and photographs were obtained from the database of endoscopy services and the pathology photos were obtained from the pathologist’s registry. A literature review based on a Pubmed search of the existing literature on clinical histories and reports of similar cases is included.

A method to continuously measure bed and water levels along a cross- shore transect of vertical poles is evaluated. This remote sensing based method uses video imagery of swash flows propagating past an array of vertical poles buried on the beach face. Using datasets collected at two beaches in Chile, the method is compared against measurements obtained with conventional co- localized instruments: LiDAR and ultrasonic distance meters. The present video swash pole technique shows good skill in retrieving swash zone bed level and water levels, while providing the possibility to measure morphological variations at time scales varying from wave groups ( tens of seconds) to hours. Discrepancies between video and ultrasonic distance meters are found when short time scales are used, for both depositional and erosion events, but longer duration trends are captured well. Water surface elevations at the wave- by- wave scale proved to be accurate for the backwash phase ( root- mean- sqaure- error, RMSE down to 0.028 m, R2 up to 0.89), when compared against LiDAR. However, discrepancies have been found during the uprush phase ( RMSE up to 0.062 m, R2 down to 0.71), when the influence of the pole on the swash flow generates an overestimation of the water surface. Overall, owing to its simplicity of deployment, low cost and reasonable accuracy, the technique is considered suitable for swash studies.

The importance of the submersion regime for the physiology, behavior and ecology of intertidal organisms, as well as limitations of available measurement methods, motivated us to develop a new remote sensing method. This new method is based on video monitoring of visual references installed at interest positions in the intertidal zone. Video imagery processing algorithms discriminate between states of submersion and emersion. The signal is based on the fluctuation in the color contrast between the visual reference and the adjacent rock. Our remote sensing method was validated favorably by comparing with direct field observations of submersion time series and comparison of different submersion metrics, including submersion percentage and maximum emersion duration. Since the remote sensing method captures and stores imagery remotely, obtaining long records of high temporal resolution is facilitated and the risk of discontinuity of time series is reduced in comparison to the use of sensors at the zone of wave impact. The high temporal resolution is critical for environments with high exposure to waves and allows for reliable estimates of a wide variety of relevant submersion metrics. This low cost remote sensing method should encourage quantification of submersion regimes of organisms inhabiting rocky intertidal zones, as well as the exploration of physiological, behavioral and ecological consequences of these regimes. Identifying the character of the forces underlying submersion regimes, together with critical environmental variables, such as temperature and solar radiation, will allow better hind-casts and forecasts of the ecological consequences of past and future climate change on these communities.

Forecasting the tsunami hazard is a challenging task due to the inherent uncertainties, both epistemic or aleatoric, that exist in determining the occurrence, magnitude and slip distribution of the parent earthquake. As a result, the typical approach reli

Tsunami inundation maps are powerful tool to design evacuation plans of coastal communities, additionally can be used as guide of territorial planning and assessment of structural damages in port facilities. The precision of inundation estimation is highl

On 1 April 2014, an earthquake with moment magnitude Mw 8.2 occurred off the coast of northern Chile, generating a tsunami that prompted evacuation along the Chilean coast. Here tsunami characteristics are analyzed through a combination of field data and

International audience; In the nearshore, describing the complex individual wave dynamics remains a key challenge. In this paper we test the ability of the Radon Transform to produce estimates of individual wave celerities and to separate incoming and outgoing waves conserving the temporal characteristics. The Radon Transform is a projection of a two-dimensional field into polar space. Oblique features such as propagating crests in a spatio-temporal space are identified with density peaks in the polar space. In this paper, the Radon Transform is applied to synthetic test cases including a wide range of beach slopes and wave conditions. The Radon Transform shows good skills at estimating individual celerity and separating incoming and outgoing components with a relative RMS error lower than 10%, even a standing wave node. The accuracy is fairly insensitive to wave characteristics whereas the main limitations rise from the sampling scheme and are the number and density of wave gauges. The distance between gauges should be less than one third of the shortest wavelength, while the set of gauges should cover more than one third of the longest wavelength.

This article presents an overview of the different processes of data recollection and the analysis done by different stakeholders during and after the emergency caused by the 2010 Maule earthquake in central-south Chile. The article is not an exhaustive r

Alternative wave transfer methodologies from deep to shallow water that aim at reducing the computational time in cases where the full propagation of a large number of wave climates is often prohibitive are defined and tested against full spectral propaga

A conceptual analysis of the coupling between bars and infragravity waves is performed combining laboratory experiments and numerical modeling. Experiments are carried out in a wave flume with a barred profile. The Boussinesq fully-nonlinear model SERR1D is validated with the laboratory data and a sensitivity analysis is performed next to study the influence on the infragravity wave dynamics of bar amplitude and location, and swash zone slope. A novel technique of incident and reflected motions separation that conserves temporal characteristics is applied. We observe that changing bar characteristics induces substantial variations in trapped energy. Interestingly, a modification of swash zone slope has a large influence on the reflected component, controlling amplitude and phase time-lag, and consequently on the resonant pattern. Variations of trapped infragravity energy induced by changes of swash zone slope reach 25 %. These changes in infragravity pattern consequently affect short-wave dynamics by modifying the breakpoint location and the breaking intensity. Our conceptual investigation suggests the existence of a morphological feedback through the action of evolving morphology on infragravity structures which modulates the action of short-waves on the morphology itself.

Powdery mildew (Erysiphe cichoracearum) limits pumpkin (Cucurbita moschata) production in Puerto Rico and other areas of the Caribbean. In order to effectively use half-sib family recurrent selection to develop polygenic mildew resistance we tested various inoculation methods to determine which method can best be used to quantify small differences in resistance. Dusting leaves using infected plant tissue was a fast and effective method that would be useful in a screening program where many genotypes need t4o be evaluated but where resistance need not be quantified. Spraying with a 1 x 10 spores/cc triton suspension was an efficient method for a recurrent selection program where small differences in resistance among families must be determined.