Tsunami

A nuclear accident is defined by the International Atomic Energy Agency (IAEA) as an incident in which people died or property damage topped $50,000. In 1990, IAEA introduced the International Nuclear and Radiological Event Scale (INES) to rate and rank nuclear accidents. INES is a logarithmic scale that consists of seven levels: 0 (Deviation, no safety significance), 1 (Anomaly), 2 (Incident), 3 (Serious incident), 4 (Accident with local consequences), 5 (Accident with wider consequences), 6 (Serious accident) and 7 (Major accident).

The Fukushima Daiichi power plant located in the port town of Okuma in the Fukushima Prefecture, northeast Japan, has six boiling-water-type nuclear reactors supplied by General Electric (units 1, 2 and 3), Toshiba (units 3 and 5) and Hitachi (unit 4) for

Before it happened, it was hard to imagine that a combined megaquake and tsunami in Japan could cascade to a nuclear disaster. Yet that’s exactly what happened at the Fukushima Daiichi (Number 1) nuclear power plant, 220 kilometers northeast of Tokyo, last month. This incident has put Japan’s nuclear policy in the spotlight, but its implications go far beyond a single country.

Usually, when a major natural disaster strikes, a population becomes more alert and aware. People know what warning signs to watch for; they know what to do should such an event occur again. They increase their chances of staying alive. For example, intergenerational knowledge of tsunamis passed down by island tribes around the Indian Ocean is credited with saving lives during the 2004 Indian Ocean tsunami.

Guatemala's Pacaya volcano and Ecuador’s Tungurahua vociferously erupted on Thursday, wreaking havoc on villages and cities nearby.

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As you would expect, there's been tons of coverage of the earthquake off the coast of Chile and the resulting tsunami in the mainstream media. And some of it has been notoriously poor.

A quake in Tajikistan in Central Asia left thousands of people homeless, and earthquakes and a tsunami devastated parts of the Solomon Islands in the South Pacific.

Updated on Sept. 30:

A tsunami spawned by Tuesday's earthquake, which struck in the Pacific Ocean between American Samoa and Samoa, swept across the islands on Tuesday, local authorities reported Wednesday. Authorities in the region are reporting that the death toll from the earthquake and tsunami has risen to at least 111 people, including 22 people in American Samoa, 82 people in Samoa and seven in Tonga, according to a report by CNN.

About four years ago, a group of scientists proposed that a series of giant, wedge-shaped sandy deposits found along the shores of southern Madagascar might be evidence of a giant tsunami — a “mega-tsunami” — generated by an asteroid that may have blasted into the Indian Ocean sometime in the last 10,000 years. Furthermore, the scientists said, such impacts and the resulting tsunamis may have occurred fairly frequently during this period. To search for evidence of these impacts, the researchers formed the Holocene Impact Working Group.

A magnitude-7.5 earthquake rocked through Indonesia's island of Sulawesi at about 1 a.m. local time Monday, leaving four people dead and prompting thousands to flee their homes. Following the mainshock, the region also experienced several strong aftershocks, ranging in magnitude from 5.1 to 5.6.

The eyewitness accounts, written in columns from right to left, top to bottom, testify that there was no warning of the tsunami, no shaking to drive villagers to high ground before the wave hit, drowning rice paddies and swamping a castle moat. The entries, written by merchants, peasants and samurai, all clearly mark the time and date: just after midnight on Wednesday, Jan. 27, 1700.

On March 11, 2011, at 2:46 p.m. local time, a magnitude-9.0 earthquake ruptured a 500-kilometer-long fault zone off the northeast coast of Japan. Its epicenter was 130 kilometers off Sendai, Honshu; it occurred at a relatively shallow depth of 32 kilometers. The temblor violently shook northeast Honshu for six minutes, and collapsed its coastline by one meter.