Tsunami in the context of "Near-Earth object"

A natural disaster is the very harmful impact on a society or community brought by natural phenomenon or hazard. Some examples of natural hazards include avalanches, droughts, earthquakes, floods, heat waves, landslides - including submarine landslides, tropical cyclones, volcanic activity and wildfires. Additional natural hazards include blizzards, dust storms, firestorms, hails, ice storms, sinkholes, thunderstorms, tornadoes and tsunamis.

A natural disaster can cause loss of life or damage property. It typically causes economic damage. How bad the damage is depends on how well people are prepared for disasters and how strong the buildings, roads, and other structures are.

On 26 December 2004, at 07:58:53 local time (UTC+7), a M_w 9.2–9.3 earthquake struck with an epicenter off the west coast of Aceh in northern Sumatra, Indonesia. The undersea megathrust earthquake, known in the scientific community as the Sumatra–Andaman earthquake, was caused by a rupture along the fault between the Burma plate and the Indian plate, and reached a Mercalli intensity of IX in some areas.

The earthquake caused a massive tsunami with waves up to 30 m (100 ft) high, known as the Boxing Day Tsunami after the Boxing Day holiday, or as the Asian Tsunami, which devastated communities along the surrounding coasts of the Indian Ocean, killing an estimated 227,898 people in 14 countries, especially in Aceh (Indonesia), Sri Lanka, Tamil Nadu (India), and Khao Lak (Thailand). The direct result was severe disruption to living conditions and commerce in coastal provinces of these and other surrounding countries. It is the deadliest tsunami in history, the deadliest natural disaster of the 21st century, and one of the deadliest natural disasters in recorded history. It is also the worst natural disaster in the history of Indonesia, the Maldives, Sri Lanka and Thailand.

The 1956 Amorgos earthquake occurred at 03:11 UTC on July 9. It had a magnitude of 7.7 on the moment magnitude scale and a maximum perceived intensity of IX on the Mercalli intensity scale. The epicentre was to the south of the island of Amorgos, the easternmost island of the Cyclades in the Aegean Sea. There was significant damage on Amorgos and the neighbouring island of Santorini. It was the largest earthquake in Greece in the 20th century. It was followed 13 minutes later by a magnitude 7.2 earthquake near Santorini. It triggered a major tsunami with a maximum run-up of 30 m. The combined effects of the earthquake shaking and the tsunami caused the deaths of 53 people with a further 100 injured.

A paleotsunami is a tsunami that occurs prior to written history where there are no documented observations. Paleotsunamis are evidenced by modern technology and scientific research. One of the largest was a megatsunami resulting from the asteroid that wiped out the dinosaurs.

Studying paleotsunamis is an emerging science to identify and interpret paleotsunami deposits. There are several recorded paleotsunami records, though some are known only by historical mentions, such as tsunamis resulting from the 1700 Cascadia earthquake which is known only from oral traditions among the Native Americans of the Pacific Northwest and simultaneous Japanese accounts of the same event.

A geologist is a scientist who studies the structure, composition, and history of Earth. Geologists incorporate techniques from physics, chemistry, biology, mathematics, and geography to perform research in the field and the laboratory. Geologists work in the energy and mining sectors to exploit natural resources. They monitor environmental hazards such as earthquakes, volcanoes, tsunamis and landslides. Geologists are also important contributors to climate change discussions.

An active fault is a fault that is likely to become the source of another earthquake sometime in the future. Geologists commonly consider faults to be active if there has been movement observed or evidence of seismic activity during the last 10,000 years.

Active faulting is considered to be a geologic hazard – one related to earthquakes as a cause. Effects of movement on an active fault include strong ground motion, surface faulting, tectonic deformation, landslides and rockfalls, liquefaction, tsunamis, and seiches.

Megathrust earthquakes occur at convergent plate boundaries, where one tectonic plate is forced underneath another. The earthquakes are caused by slip along the thrust fault that forms the contact between the two plates. These interplate earthquakes are the planet's most powerful, with moment magnitudes (M_w) that can exceed 9.0. Since 1900, all earthquakes of magnitude 9.0 or greater have been megathrust earthquakes.

The thrust faults responsible for megathrust earthquakes often lie at the bottom of oceanic trenches; in such cases, the earthquakes can abruptly displace the sea floor over a large area. As a result, megathrust earthquakes often generate tsunamis that are considerably more destructive than the earthquakes themselves. Teletsunamis can cross ocean basins to devastate areas far from the original earthquake.

Sendai (仙台市, Sendai-shi; [seꜜn.dai, sen.daꜜi.ɕi] ) is the capital city of Miyagi Prefecture and the largest city in the Tōhoku region. As of 1 August 2023, the city had a population of 1,098,335 in 539,698 households, making it the twelfth most populated city in Japan.

The modern city was founded in 1600 by the daimyō Date Masamune. It is nicknamed the City of Trees (杜の都, Mori no Miyako); there are Japanese zelkova trees lining many of the main thoroughfares such as Jōzenji Street (定禅寺通, Jōzenji dōri) and Aoba Street (青葉通, Aoba dōri).In the summer, the Sendai Tanabata Festival, the largest Tanabata festival in Japan, is held. In winter, the trees are decorated with thousands of lights for the Pageant of Starlight (光のページェント, Hikari no pējento), lasting through most of December. The city is also home to Tohoku University, one of the former Imperial Universities. On 11 March 2011, coastal areas of the city suffered catastrophic damage from a magnitude 9.0 offshore earthquake, which triggered a destructive tsunami.