Many coastal cities around the world are threatened by tsunamis; some of these events have caused great impacts in recent times. The loss of human lives during these events is the main cause of concern of the authorities, and evacuation planning has been recognized as one of the best tools for safeguarding the population. In this context, urban design appears to be critical for the execution of prompt and efficient evacuation processes to safe areas; however, evacuation assessment has been traditionally carried out at a large urban scale, mostly taking into consideration urban morphology and connectivity. In the present work, urban spaces available for tsunami evacuation are explored in detail by developing a methodology to identify and classify urban micro-vulnerabilities that may reduce the capacity of the evacuation routes and hinder evacuees' safety. The method is applied to the Chilean city of Iquique, affected by an earthquake and subsequent tsunami in 2014.

The tsunami resonance leads to the amplification of wave heights and extends the duration of wave activity. For tsunami warning and coastal planning, it is important to understand resonance behavior. We characterized the tsunami resonance of trans‐Pacific events in the bays and continental shelves of Japan, focusing on the Hokkaido and Sanriku regions. We considered five tsunami events with sources in the Peru–Chile subduction zone and the Alaska–Aleutian subduction zone. Spectral analysis was applied to observed and synthetic waveforms at coastal tide gauges and offshore GPS gauges to study the frequency content of tsunami energy, and modal analysis was conducted to investigate the eigen‐modes of the natural oscillation affected by regional and local bathymetry. It was found that the signatures of trans‐Pacific tsunami sources are lost in the spectra at most coastal gauges, but they partly remain in the spectra at offshore gauges, which are affected less significantly by topography or bathymetry. The predominant periods in the spectra at most coastal gauges match the eigen‐periods of natural oscillation calculated by modal analysis. Hence, we confirmed that regional or local bathymetry is the dominant factor in the resonance behaviors of trans‐Pacific tsunami events, rather than the source location or geometry. These findings are based on the systematic assessment of trans‐Pacific sources and have implications for tsunami warning and coastal planning along the Pacific coast of Japan.

SUMMARY: The 2015 Illapel earthquake (Mw 8.3) occurred off central Chile on September 16, and generated a tsunami that propagated across the Pacific Ocean. The tsunami was recorded on tide gauges and Deep-ocean Assessment and Reporting of Tsunami (DART) tsunameters in east Pacific. Near-field and far-field tsunami forecasts were issued based on the estimation of seismic source parameters. In this study, we retroactively evaluate the potentiality of forecasting this tsunami in the far field based solely on tsunami data assimilation from DART tsunameters. Since there are limited number of DART buoys, virtual stations are assumed by interpolation to construct a more complete tsunami wavefront for data assimilation. The comparison between forecasted and observed tsunami waveforms suggests that our method accurately forecasts the tsunami amplitudes and arrival time in the east Pacific. This approach could be a complementary method of current tsunami warning systems based on seismic observations.

In 2015 and 2017 unusual ocean and atmospheric conditions produced many years’ worth of rainfall in short periods over Northern Chile’s Atacama Desert, resulting in catastrophic flooding in the town of Chañaral. However, the town is not only at risk of fluvial flooding, it is also at risk of tsunamis. Through a community mapping exercise, the authors attempted to establish the level of community awareness about tsunamis, and contrasted it with that of other types of water-related hazards facing the town (namely that of flooding due to high intensity rain). This was then compared with the results of field surveys and tsunami hazard simulations, indicating than overall the community appears to have better awareness than authorities about the threat posed by these types of events. The authors thus concluded that in cases when the community has a high level of hazard awareness (which in the case of Chile was the result of traditional knowledge being transmitted from previous generations) it would be advantageous to include them in discussions on how to improve disaster resilience.

The Sendai Framework for Disaster Risk Reduction emphasizes the need to rebuild better after a disaster to ensure that the at-risk communities can withstand a similar or stronger shock in the future. In the present work, the authors analyzed the reconstruction paths through a comparative analysis of the perspective of a community in Japan and another in Chile, and their respective local governments. While both countries are at risk to tsunamis, they follow different reconstruction philosophies. Data was gathered through key informant interviews of community members and local government officials, by adapting and modifying the Building Resilience to Adapt to Climate Extremes and Disasters (BRACED) 3As framework to a tsunami scenario. The 3As represent anticipatory, adaptive, and absorptive capacities as well as transformative capacities and respondents were asked to rate this according to their perspectives. It was found that while both communities perceive that much is to be done in recovery, Kirikiri has a more holistic and similar perspective of the recovery with their government officials as compared to Dichato. This shows that community reconstruction and recovery from a disaster requires a holistic participation and understanding.

The objective of this study was to design a university-level course focused on Nature-Based Solutions (NBS) for water pollution control. The work unfolded in three phases: the initial planning, course delivery, and assessment of learning outcomes. In the planning phase, a set of competencies was outlined using the Developing a Curriculum Method (DACUM), resulting in defined learning outcomes and a structured course outline. Subsequently, the course was conducted over a two-week period, employing a hybrid format including both online and in-person sessions. The assessments of the learning outcomes included one test, an assignment, a satisfaction survey, and the post-course feedback. As a result of the planning phase, four competencies, seven learning outcomes and four course units were defined. The participant cohort encompassed a diverse group of 50 individuals, including undergraduate and postgraduate students, professionals working in industry and institutions, and professors. The assessment of the learning outcomes showed good results. However, issues regarding the mathematical calculations and field-trip experience were noted, suggesting areas for course enhancement. The participants expressed high satisfaction levels across the various course components. Notably, 70% of the participants indicated the application of the acquired knowledge in their professional endeavors. These findings underscore the successful implementation of the course, establishing it as a pioneering university-level program in NBS for water pollution control.