oceany: Tsunami

Evidence: 100 • authority: 72

A tsunami ( (t)soo-NAH-mee, (t)suu-; from Japanese: 津波, lit. 'harbour wave', pronounced [tsɯnami]) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions, underwater explosions, landslides, glacier calvings, meteorite impacts and other disturbances above or below water all have the potential to generate a tsunami. Unlike normal ocean waves, which are generated by wind, or tides, which are in turn generated by the gravitational pull of the Moon and the Sun, a tsunami is generated by the displacement of water from a large event. Tsunami waves do not resemble normal undersea currents or…

Evidence: 65 • authority: 92

Surface-to-space atmospheric waves from Hunga Tonga-Hunga Ha'apai eruption.. The January 2022 Hunga Tonga-Hunga Ha'apai eruption was one of the most explosive volcanic events of the modern era 1,2 , producing a vertical plume that peaked more than 50 km above the Earth 3 . The initial explosion and subsequent plume triggered atmospheric waves that propagated around the world multiple times 4 . A global-scale wave response of this magnitude from a single source has not previously been observed. Here we show the details of this response, using a comprehensive set of satellite and ground-based observations to quantify it from surface to ionosphere. A broad spectrum of waves was triggered by th…

Evidence: 65 • authority: 92

Tsunami Runup and Inundation in Tonga from the January 2022 Eruption of Hunga Volcano.. On January 15th, 2022, at approximately 4:47 pm local time (0347 UTC), several weeks of heightened activity at the Hunga volcano 65 km northwest of Tongatapu, culminated in an 11-h long violent eruption which generated a significant near-field tsunami. Although the Kingdom of Tonga lies astride a large and tsunamigenic subduction zone, it has relatively few records of significant tsunami. Assessment activities took place both remotely and locally. Between March and June 2022, a field team quantified tsunami runup and inundation on the main populated islands Tongatapu and Eua, along with several smaller i…

Evidence: 65 • authority: 72

A megatsunami is an extremely large wave created by a substantial and sudden displacement of material into a body of water. Megatsunamis have different features from ordinary tsunamis. Ordinary tsunamis are caused by underwater tectonic activity (movement of the earth's plates) and therefore occur along plate boundaries and as a result of earthquakes and the subsequent rise or fall in the sea floor that displaces a volume of water. Ordinary tsunamis exhibit shallow waves in the deep waters of the open ocean that increase dramatically in height upon approaching land to a maximum run-up height of around 30 metres (100 ft) in the cases of the most powerful earthquakes. By contrast, megatsunami…

Evidence: 53 • authority: 80

Uncertainty in tsunami wave heights and arrival times caused by the rupture velocity in the strike direction of large earthquakes

Evidence: 53 • authority: 88

Characteristics of Leading Tsunami Waves Generated in Three Recent Tsunami Events. In this paper, the time series of ocean water surface elevation, recorded by Deep-ocean Assessment and Recording of Tsunamis (DART) sensors in the Pacific Ocean, during three recent tsunami events — 2010 Chile tsunami, 2011 Tohoku tsunami, and 2012 Haida Gwaii tsunami — are analyzed. The characteristics of leading tsunami waves are examined in terms of their propagation speed, wave period and wave amplitude so as to determine the importance of wave nonlinearity and frequency dispersion. Using the estimated arrival time of leading waves at each DART station and the distance from each station to the epicenter o…

Evidence: 53 • authority: 72

In December 2021, an eruption began on Hunga Tonga–Hunga Haʻapai, a submarine volcano in the Tongan archipelago in the southern Pacific Ocean. The eruption reached a very large and powerful climax nearly four weeks later, on 15 January 2022. Hunga Tonga–Hunga Haʻapai is 65 kilometres (40 mi) north of Tongatapu, the country's main island, and is part of the highly active Tonga–Kermadec Islands volcanic arc, a subduction zone extending from New Zealand to Fiji. On the Volcanic Explosivity Index scale, the eruption was rated at least a VEI-5. Described by scientists as a "magma hammer", the volcano at its height produced a series of four underwater thrusts, displaced 10 cubic kilometres (2.4 c…

Evidence: — • authority: 80

Modern reservoirs with dam heights of tens and hundreds of meters above the river coastline with flooding of cities, villages, territories – this is a crime against humanity and nature. It is quite possible to eliminate floods.

Evidence: — • authority: 80

New model of the Barry Arm landslide in Alaska reveals potential tsunami wave heights of 2 meters, values much lower than previously estimated

Evidence: — • authority: 72

The Cumbre Vieja tsunami hazard refers to the risk that a volcanic eruption on the island of La Palma, Canary Islands, Spain, could cause a large landslide triggering a megatsunami in the Atlantic Ocean. Volcanic islands and volcanoes on land frequently undergo large landslides/collapses, which have been documented in Hawaii for example. A recent example is Anak Krakatau, which collapsed to cause the 2018 Sunda Strait tsunami. Steven N. Ward and Simon Day in a 2001 research article proposed that a Holocene change in the eruptive activity of Cumbre Vieja volcano and a fracture on the volcano that formed during an eruption in 1949 may be the prelude to a giant collapse. They estimated that su…

Evidence: — • authority: 72

Tsunamis in lakes are tsunamis generated by the displacement of water within large inland bodies such as lakes and reservoirs. Like oceanic tsunamis, they are typically caused by sudden geological or physical disturbances, including earthquakes, landslides, volcanic activity, or icefalls. These events can rapidly displace large volumes of water, producing waves that travel across the body of water and impact surrounding shorelines. Although generally smaller in scale than oceanic tsunamis, lake tsunamis can still produce significant local effects, including shoreline flooding, erosion, and damage to infrastructure near water margins. They are most commonly associated with steep-sided lakes…