Tsunamis Flashcards
What is a Tsunami?
A series of abnormally large waves often over several hours
Where do most tsunamis originate?
Most tsunamis originate at plate margins
What are many tsunamis triggered by?
72% of tsunamis are triggered by seafloor EQ’s at subduction zones
What causes 5% of tsunamis?
Volcanic eruptions
What is an example of a volcanic eruption causing a tsunami?
Anak Krakatau 2018, Indonesia due to landslides, glacier breakup and meteorites
How destructive can large tsunamis be?
Large tsunamis may travel many km inland and change the landscape uprooting trees and destroying farmland, infrastructure and people can be swept away
What causes most deaths in a tsunami
Deaths are mainly a result of drowning, however there can also be deaths as a result of building collapse and being stricken by debris
How can tsunamis lead to disease such as cholera?
Land, food and water get contaminated with salt, sewage and even bodies
How does the DART tsunami warning system work?
A recorder on the seabed monitors changes in pressure, an acoustic link transmits data to a moored surface buoy, this data is then relayed to a satellite and the satellite transmits the data to a ground station
What happened in the Palu 2018 tsunami in Indonesia?
The warning system failed, drastically underestimating the scale of the tsunami, leading to thousands of deaths
What happened when the Indian Ocean 2004 tsunami made landfall with Sri Lanka?
The tsunami made landfall with Sri Lanka in 2 hours killing 31,000 people
What happened in the Indian Ocean in 2004 on boxing day?
A tsunami devastated countries surrounding the ocean
Why is retreating water a sign of a tsunami?
When the crest of a tsunami reaches the shore it creates a vacuum effect sucking the coastal water out to sea
