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The Sumatra-Andaman arc is an active subduction zone that has generated several destructive tsunamis. The December 26, 2004, Sumatra-Andaman earthquake of magnitude Mw∼9.3 generated the most destructive tsunami known to man. The sustained high water level in several regions on the east coast of India due to tsunamis in the Bay of Bengal can be attributed to the reflection of direct tsunami waves and trapping of wave energy. In this paper we have simulated two scenarios of tsunamigenic earthquakes, the 2004 Sumatra earthquake and a possible great earthquake in the Andaman region. Tsunami wave propagation and inundation at Visakhapatnam due to these two earthquakes have been modeled. We find that the tsunami run-up heights for the 2004 Sumatra earthquake were about 1.5 m. For the other possible scenario, we observed that the run-up is about 3–4.6 m. The inundated distances have been estimated and are 1–2 km.

An earthquake occurred off the west coast of Nicaragua at 18 h 16 m on September 1, 1992. Despite a relatively modest magnitude (Ms = 7.0 Mw = 7.6), the earthquake generated a significant tsunami, which strongly impacted the coast of Nicaragua and was felt at several remote stations. In an attempt to better understand the tsunami propagation and coastal impact, we conducted a field survey on November 2–7, 1992, i.e., roughly 2 months after the event. We emphasized the observation of run‐up and inundation, but also collected a limited number of sand samples and mud cores. A total of 12 sites were surveyed, with multiple stations per site. This article presents the results of the survey, including a detailed discussion of the observation methods and data processing strategies. Observed run‐ups (relative to MSL) were typically in the 4–7 m range, with a maximum run‐up of 9.1 m at San Martin, an open coast site with a steep beach slope. Inundation extents were relatively modest, typically of the orde...

The dynamics of tsunamis can be divided, for convenience, into three parts: tsunami generation, tsunami propagation, and the coastal problems. Out of these three, the problem of tsunami propagation is probably better understood than the other two. One of the main hindrances to the quantitative prediction of tsunami amplitudes at various coastal locations is a lack of detailed knowledge about the deep water signature of a tsunami. Here, the present understanding of this problem is discussed.

A numerical procedure is given for the computation of the reflection and transmission of two‐dimensional, long‐time harmonic waves in natural fluid basins.

The preliminary scheme of Kurilo‐Kamchatka region tsunami zonation was made through numerical calculations by means of shallow water equations. The coast considered is 800 km long. The mean increase of the wave height is 2–3 along the coast, and in several places is up to 5–7. In Kamchatsky Bay the tsunami propagation is estimated. Because of refraction and interference of reflected waves, the level oscillations in the northern part of Kamchatsky Bay are determined mainly by the local bottom topography and the coastline features, while their dependence on the initial source orientation is slow. The calculation shows that the effect of both nonlinearity and friction is of weak influence up to the 10‐m bottom contour. The maximum decrease of height may be evaluated as 13%. In addition, the nomogram is constructed, permitting the determination of the inundation of the dry coast slope depending on the bottom slope and the height of the approaching wave. The determination of the distribution of the wa...