How do you know a tsunami is coming if you are at the beach? There are two ways: a natural warning or an official warning.
An unusual lowering of the ocean water that exposes the sea floor is a dramatic warning that a tsunami or tidal waves are coming. The drawback of water is followed by a strong surge of water. There can also be an earthquake or loud ocean roar. If so, get out of the water immediately and move to higher ground or inland as quickly as possible.
On the eastern coast of Japan, back in 1991, a group of swimmers were swimming along the coastline and felt a strong, immediate pull out towards the ocean. It was nothing like they ever felt before. It was similar to the strong seaward surge near a pier or jetty when there is high surf and the water naturally flows outward from the shore.
Once an earthquake hits, the tsunamis may arrive in minutes and may last for more than eight hours. This is what recently happened in northern Japan which devastated hundreds of kilometers of coastline in eastern Japan (see below).
When the earthquake and tsunami hit Japan, a group was in Molokai getting ready for Penny Palfrey’s first attempt of the Molokai Channel in March 2011. After her support team completed their final preparations and started to get in bed for a few hours sleep before heading out for an early morning start, the hotel manager frantically knocked at their door, alerting them to move to higher ground. “An earthquake hit Japan and we expect a tsunami soon,” were his quick explanation as he continued to warn the other hotel guests.
The hotel lobby was quickly filled with sleepy-eyed guests with obviously hastily filled luggage. “Follow us. Head towards the shelter,” were among the bits of advice that were shared. “We’re leaving now.”
So the night before her Molokai Channel swim was spent in a high school gymnasium, trying to get news of the situation and catching a few winks of sleep nestled in the bleacher seats. Coffee, hot chocolate, instant noodles and snacks were provided while idle chatter was interrupted by an occasional report of damage in Japan and the Hawaiian shoreline.
The official warnings are deliver by television, radio, news alerts and the Internet. Sometimes, there are also sirens or door-to-door or street-by-street contact by emergency responders.
Beaches, lagoons, bays, estuaries, tidal flats and river mouths are the most dangerous places to be when a tsunami hits the shore. The first tsunami surge is not the highest. The largest surge may occur hours after the first wave. Every tsunami is different. It is not possible to predict how many surges or how much time will elapse between waves for a particular tsunami.
So be warned. Tsunamis and earthquakes can strike at any time.
Copyright © 2011 by Open Water Source