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In this article, we estimate the tsunami hazard in Martinique due to tsunamis generated by earthquakes associated with the Lesser Antilles subduction zone. Using a deterministic approach based on reliable earthquake scenarios, we use high‐resolution bathymetric and topographic data to model tsunami propagation and inundation with Cornell Multi‐grid Coupled Tsunami model. An extreme earthquake subduction scenario of magnitude Mw 8.0 is tested, and a further realistic scenario of lower magnitude Mw 7.5, thus of different tsunami frequency content, is also processed to test the possible appearance of bay resonances. We find that the western coast of the island is relatively sheltered, because it represents a shadow area to diffraction, in particular, for the major city of Fort de France. Because of its very gentle slope, the eastern coast is prone to numerous floodings with meter scale wave amplitudes; most of the inundated zones consist of mangroves and geological depressions t are naturally regularly flooded by tides or storm surges. Hence such areas are often not exploited, the mangroves being let in their natural state, enhancing the protection of the surrounding communities. However, some strategic inhabited areas are subject to severe inundation. Finally, comparing our results with studies of the 1755 Lisbon transoceanic tsunami reveals a tsunami hazard close to our local Mw 7.5 scenario. It suggests the possibility to generalize our local tsunami hazard assessment in Martinique to other tsunami contexts and enlarge its validity. This issue is crucial for minimizing the efforts and increasing the efficiency of tsunami preparedness

P>Shelf promontories exhibit very specific bathymetric features with regards to tsunamis. Because of their submerged cape morphology, a potential tsunami generated seawards of the promontory will exhibit a specific mode of propagation and coastal impact. To identify this peculiar tsunami signature, the Atacames Promontory, Ecuador, was chosen as a case study (another example is the shelf of the Nile delta, Egypt). The area is tectonically very active, hosts earthquakes among the most powerful recorded, as well as areas of slope instabilities that have triggered significant submarine landslides in the past (several cubic kilometres of volume). Both types of events are likely to be tsunamigenic. To examine the tsunami behaviour at the coastal area of the promontory and at its vicinity, we have considered two examples of tsunamigenic landslides of which scars were identified near the base of the continental slope. We also took into consideration two earthquake scenarios that are likely to represent most classes of earthquakes possibly occurring in this area depending on their locations and subsequent tsunami directivity, that is, a sensitivity test investigation. We took two distinct earthquake scenarios which are based on the 1942 and 1958 events that stroke the area. Then we computed their derived tsunamis and analysed their coastal impact. We found that significant tsunamis can be generated by either landslides or earthquakes. However, the maxima of wave amplitude occur offshore (but still above the underwater promontory): the concave-type shape of the bathymetric field often yields a refraction/focusing area that is located on the shelf promontory and not at the coast area of the promontory: the wave propagates first through the focusing area before striking the considered coast. This area may be considered as a sheltered zone. Besides, in the vicinity of the promontory (not exactly concerned by the study), the city of Esmeraldas, is relatively sheltered due to the

Khao Lak, SW Thailand was severely affected by the tsunami on 26 December 2004. Here we present reconstructions of its coastal impact in this area. These are based on (1) eyewitness reports alone and (2) eyewitness reports supported by videos and photos of the tsunami and the damage it caused, field measurements, and satellite imagery. On the basis of eyewitness reports, we estimated that the sea began retreating at 1000 local time (LT) and, based also on photos, that the tsunami arrived at 1026-1029 LT. On the basis of videos of the tsunami, we estimated an offshore wave direction of 083 +/- 3 degrees and on the basis of the paths by which eyewitnesses were carried, we estimated an onshore direction of 088 +/- 6 degrees. On the basis of videos, we calculated that the velocity of the wavefront on its final approach was 33 +/- 4 km/h. We obtained tsunami heights of 7.3 +/- 0.8 m (relative to ground level) on the basis of eyewitness reports and 8.0 +/- 0.6 m (relative to mean sea level) on the basis of field and photographic data. On the basis of eyewitness reports and photos, we concluded that Khao Lak experienced at least two main waves with a period >40 min. From eyewitness reports and satellite imagery, we measured maximum inundation <= 0.5 km in the southern part of the area, which is confined by a steeply sloping hinterland, and <= 1.5 km in the more gently sloping northern part. Comparison between these reconstructions supports the reliability of eyewitness reports as a source of quantitative data, and comparison with the numerical simulation by Ioualalen et al. (2007) supports the validity of the simulation.