TSUNAMI

As New Zealand is surrounded by water many places by the coast are at risk from tsunami. In a tsunami the water level may fall very quickly past the normal low tide mark, then return just as quickly. If this happens, there won't be enough time to issue a warning so it is important that you know what to do. You must get to high ground, away from the beach, quickly.
Sometimes tsunami travel across the ocean from far away and we have more time to warn people what to do.

 

Tsunami warning sign

Tsunami is a Japanese word meaning ‘harbour wave’. A tsunami is a series of fast travelling waves caused by a large disturbance in the sea or on the ocean floor. An earthquake, landslide, volcanic eruption or meteorite can cause the disturbance. The waves can be separated by as much as an hour apart. They can travel many thousands of kilometres across the oceans at great speeds of up to 800 kilometres per hour.

A tsunami may not be noticed as it crosses deep oceans, but it loses speed and gains height when it reaches shallow water. Large waves up to 15 metres or more in height can come crashing onto the land. The effects can be worse in narrow bays and inlets.

Tsunami waves appear either as rapidly-moving tides with very strong currents that can wash people and objects out to sea, or as large breaking waves that can cause major damage when they hit the shore.

Tsunamis can be caused from big earthquakes in the sea very close to New Zealand. If you feel an earthquake that lasts longer than one minute, or one that is so strong it is hard to walk around or stand up, a tsunami could follow it. Sometimes when tsunami waves arrive on shore it looks like the water has been sucked out before it rushes back in, or the waves make unusual noises like a jet engine. However, these don’t always happen. If you are near the beach and feel a long or strong earthquake, or you see or hear this unusual ocean behaviour, there won’t be enough time to issue a warning. It is important that you know what to do, and that you get to high ground away from the beach as quickly as you can.

What do we do before a tsunami?

  • Talk with your family and prepare an emergency plan.

  • Identify safe places close to you at home or school.

What do we do during a tsunami?

  • Move immediately to the nearest higher ground, or as far inland as you can. Walk or bike if possible.

  • If you do not have time to move to higher ground or inland, go to an upper storey of a sturdy building, climb onto a roof or up a tree.

  • Do not go sightseeing. Never go to the shore to watch for a tsunami.

  • Stay away from at-risk areas until the official all-clear is given.

What do we do after a tsunami?

  • Stay calm.

  • Listen to, and follow, instructions from adults or the radio.

  • Help others who may need it, if you can.

Home learning

IzzyIdentify safe places close to your home and school.

Ask an adult to help you take a picture of a safe place that can be shared to the Civil Defence Twitter feed @NZcivildefence

Make a plan with your family to get through an emergency. Think about the things you need every day and work out what you would do if you didn't have them. 

Make your plan  – print it out, stick it on the fridge and make sure everyone knows the plan. 

Tsunami classroom activities

These are some learning activities you might like to try in the classroom:

Stan

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