Tsunami Flashcards
Generated by sudden displacement of the seafloor
Tsunami
Enumerate the parts of the wave
Wavelength, wave height, amplitude, frequency, velocity
Distance between wave crest and wave troughs
Wavelength
Normal ocean wavelengths have a typical length of ________.
100 m
Tsunami have a typical wavelengths of ________.
500 km
The rate at which a wave loses its energy is ________ related to its wavelength.
inversely
Distance between the trough of the wave and the crest of the wave.
Wave Height
Equal to 1/2 the wave height
Wave amplitude
Amount of time it takes for one full wavelength to pass.
Wave frequency
Wind-generated waves usually have period of ______________.
Five to twenty seconds
Tsunami wave can have a time period of __________.
Ten minutes to Two Hours
Normal ocean waves have a velocity of _______.
90 km/hr
Tsunami have velocities up to _________.
950 km/hr
Formula of wave velocity
Wave velocity is equal to the wavelength divided by the wave period.
If the trough of the tsunami wave reaches the coast first, this is called ________.
Drawdown
The term for the crest of the wave hits, sea level rises.
Run-up
NOAA
National Oceanic and Atmospheric Administration
What is Pacific Tsunami Warning Center
Consist of an international network of seismographic stations and tidal stations around the Pacific basin that can send information via satellite to the center located in Hawaii
Enumerate tsunami safety rules
Keep calm and move to higher ground
Notice the rise or fall of coastal waters
Stay out of danger until an “all clear” is issued by a competent authority
Never go down to the beach to watch a tsunami
The upper floors of the building can provide a refuge
If you are in a ship, move your boat into a deeper water
Stay updated with the credible source
List of Tsunami Network in the Philippines
Bolinao-TEWS
Dapa-JICA
Guimbal-SATREPS
What is TEWS
Tsunami Early Warning Signs
What is SATREPS
State of the Art Technologies to Strengthen Research and Response to Seismic, Volcanic and Tsunami Events, and Enhance Risk Management
Enumerate the ways the tsunami can be generated.
Earthquakes
Volcanic eruptions
Landslide
Underwater explosion
Meteorite impacts
Collapse of underwater volcanoes
Controlling factors of tsunami occurrence.
Epicenter
Magnitude
Type of displacement
Tsunamis are generated along the _______ of the plates.
subduction boundaries
How can volcanic eruptions cause tsunami?
Explosive eruptions can rapidly emplace pyroclastic flows into the water, landslides and debris avalanches produced by eruptions can rapidly move into water, and collapse of volcanoes to form calderas can suddenly displace the water.
A large Plinian eruption column blasted pumice and ash up to 40 km into the atmosphere
How can landslide cause tsunami?
Most of these landslides are generated by earthquakes or volcanic eruptions
A debris avalanche fell into Lituya Bay, Alaska in 1958 causing a wave with a run up of about 60 m as measured by a zone completely stripped of vegetation
How can an underwater explosion cause tsunami?
Human induced
Nuclear testing by the United States in the Bikini Atoll in Marshall Islands in the 1940s and 1950s generated up to 30 m high tsunamis
How can a meteorite impacts cause tsunamis?
While no historic examples of meteorite impacts are known to have produced a tsunami, the apparent impact of a meteorite at the end of the Cretaceous Period, about 65 million years ago near the tip of what is now the Yucatan Peninsula of Mexico, produced tsunami that left deposits all along the Gulf coast of Mexico and the United States