Before the Boxing Day tsunami of 2004, many were not aware that gigantic tidal waves were a natural phenomenon, let alone a force of nature that could kill. On the 26th December, a tsunami occurred in the Indian Ocean. It was the result of a magnitude nine earthquake by two plates on the seafloor, displacing the ocean above.
At its start, the tsunami measured no more than one metre high. However, the force of the earthquake resulted in the tsunami travelling to shore at speeds of up to 800km per hour, with waves 15 meters high hitting the shores of India, Indonesia, Malaysia, the Maldives, Myanmar, Somalia, Sri Lanka, Thailand, Bangladesh, South Africa, Madagascar, Kenya, Tanzania and Seychelles.
Over a quarter of a million people lost their lives due to the 2004 tsunami and a further two million were made homeless. Since 2004 there have been 14 further tsunamis and expats moving to countries prone to earthquakes should be aware of how to act.
Tsunami Hazard Zones
Any country in the world that has a coastline can experience a tsunami, including areas with ice and snow. However, the Pacific Ocean has had the most tsunamis due to the tectonic plates which lie below its surface. Therefore, east Asia, eastern Australia, New Zealand and the west coasts of North and South America are considered the most at risk.
Low lying coastal areas are likely to be the worst affected if a tsunami were to hit. Waves can reach up to 30 meters in extreme cases and they can move inland for hundreds of meters.
Signs of Tsunami
If you are living in a low lying coastal area and experience a sizeable earthquake it is best to be on your guard. Not every earthquake results in a tsunami but it is best to be aware of your surroundings, particularly if you feel the ground shake severely for a long time.
You will be able to HEAR tsunami as a roaring noise similar to a train.
You will be able to SEE a tsunami as a wall of water in the distance. Often this is preceded by a rapid fall in sea level which exposes the sea floor, reef and fish.
What To Do When a Tsunami Hits
If you feel an earthquake do not wait for the authorities to issue a tsunami warning. Move as far away from the coast, rivers and estuaries as possible and head for higher ground. It is better to be safe than sorry.
Tsunami zones will have tsunami warning sounds and evacuation protocol and centres. Expats living in tsunami zones should make themselves aware of local procedures.
If you have been caught out by a tsunami RUN inland to higher ground.
How Long Do Tsunamis Last?
Tsunamis are not one giant wave. Waves of varying size will reach the coast every 5 to 60 minutes and the first wave is not always the largest. Each wave pushes massive volumes of water on to the land so never leave safety until the authorities have given the all clear; this could be several hours after the first wave.
- Tsunamis can cause severe flooding and damage. If you are trapped do not move and wait for the authorities to collect you.
- Tsunamis can occur day and night
- Tsunamis can travel up rivers and estuaries
- Tsunamis can wrap around islands
Always assume that an earthquake will result in a tsunami.
Always assume that the tsunami will be the worst and take appropriate action.
Tsunami Warning Centres
If you live in a low lying coastal area that is at risk your country will have a national tsunami warning centre and local officials. Scientists will constantly be monitoring the ocean and if there is a threat of a tsunami they will issue a tsunami warning. Emergency officials in your locality will issue evacuation orders.
Your Tsunami Warning Centre will cancel a tsunami warning when the destructive waves have ceased. You will be able to return home once emergency officials have deemed your property safe.
What To Do After a Tsunami
Some tsunamis cause nothing more than streets filled with debris whereas others tear towns down and result in huge loss of life. If you experience a non-destructive tsunami the authorities will let you return to coastal areas shortly.
If your town has been hit by a destructive tsunami the cleanup operation can take anywhere from hours to days, to weeks. Emergency search and rescue operations will be in full effect and you will not be able to re-enter coastal areas until they have been cleared and considered safe.
Your local authorities will have measures put in place to accommodate tsunami evacuees until you can go back to your home.