WEEK 13 - Tsunami Flashcards
What is the origin of the word “tsunami”?
Tsunami comes from Japanese:
“Tsu” = harbour
“Nami” = wave
Why are tsunamis often incorrectly called “tidal waves”?
Tsunamis are often mistakenly referred to as tidal waves, though they are different phenomena.
What is the significance of tsunamis in Japanese art?
Tsunamis have been important in Japanese art, such as in Hokusai’s famous work:
- The Great Wave off Kanagawa
- Woodblock print, created in the early 1830s
What causes a tsunami?
Vertical displacement along a fault on the ocean floor
A large undersea landslide triggered by an earthquake
Other disturbances, such as a meteorite impact
What is the wave height of a tsunami in the open ocean?
Less than 1 metre.
Why do tsunami waves get taller in coastal waters?
In shallower coastal waters, the wave height increases due to friction generated on the seafloor.
Waves can sometimes exceed 30 metres in height.
What happens when a tsunami wave reaches shallow waters?
The tsunami wave breaks when it can no longer support itself due to the build-up of water.
2011 Japan Earth Quake
Date: Friday, March 11, 2011 at 2:46:23 PM.
Magnitude: 9.0.
Epicenter: The earthquake occurred offshore, about 130 km east of Sendai, Japan, and 375 km northeast of Tokyo.
Depth of Focus: 13.5 km below Earth’s surface.
2011 Japan Tsunami
Height: 23.6 m high.
How fast did it hit after earthquake: 15 minutes
How far waves travelled: 10 km inland
Human Impact from Tsunami x Earthquake in Japan
15,899 deaths
2,778 injuries
17,339 missing
Over 125,000 buildings damaged or destroyed
4.4 million households without electricity
1.5 million households without water
What was the tsunami warning issued for the 2011 Japan earthquake?
Warning issued by Japan Meteorological Agency
Rated as a “major tsunami” (at least 3 m high)
What was the predicted tsunami height for Miyagi during the 2011 Japan earthquake?
Greatest predicted height: 10 m for Miyagi
How large was the area affected by the tsunami in Japan?
Inundated area: Approximately 470 square kilometers in Japan
Did the 2011 Japan tsunami travel across the Pacific?
Yes, the tsunami travelled across the Pacific
It was observed on the North American coastline
How quickly did the 2011 Japan tsunami travel to California?
Tsunami speed: 500 km/hr
Time to reach California: Less than 12 hours after the main earthquake
What were the longer-range consequences of the 2011 Japan earthquake and tsunami?
- Cost: $360 billion
- The most expensive natural disaster on record
- Fukushima nuclear facility: One of the most serious concerns
What was the status of the nuclear crisis after the 2011 Japan earthquake and tsunami?
Cooling systems failure: Led to overheating and meltdown in 3 reactors
Radioactive steam: Escaped from at least one reactor building
Evacuations: Over 140,000 residents were evacuated early
Long-term effects: Radiation contamination in air, water, and soil still being assessed
Can short-range earthquake predictions be made?
No reliable method exists for predicting earthquakes in the short term.
What are long-range earthquake forecasts?
Predict the probability of an earthquake of a certain magnitude occurring over 30–100 years.
Based on historical records and rates of fault movement.
How are tsunami warnings used to reduce damage?
Early warning systems can help reduce damage.
Tsunamis can take hours to reach distant shores, so timely warnings are critical.
Is tsunami warning technology available in all tsunami-prone areas?
Technology for tsunami warnings is lacking in many tsunami-prone areas.
