Anniversary of Japanese tsunami

It’s the first anniversary of the devastating tsunami in Japan today.  A reminder of the real power of nature.  And the risks of man- made development.  All our thoughts go out to those who were affected – many of whom will still be trying to rebuild their lives.

Tsunami are often referred to as tidal waves.  The word is Japanese from tsu meaning harbour and nami meaning wave.  Out in the ocean the tsunami are usually not more than half a metre in height, but when they come close into shore they can reach heights of 30 to 35 metres.  In 1971 one measured at 85 metres occurred in Japan.  Most tsunami are caused by earthquakes.  They can travel huge distances such as right across the Pacific Ocean. 

The most effective mitigation against tsunami is to evacuate all people who are likely to be affected.  It was striking that not many Kiwis were killed in the Boxing Day tsunami in Asia – we are brought up knowing that unusual drawing back of the waves is a sign to head for the hills.