7:23 PM Sat 27 Feb 2010 GMT
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'Tsunami waves with times from Chile 8.8 magnitude earthquake'
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Tsunami warnings have been posted around the Pacific, including New Zealand, Mexico, the USA's Hawaii and California, Japan and Russia and the Australian East Coast (south of Queenslands Double Island Point to the southern tip of Tasmania) after a massive earthquake near Chile's second largest city Conception.
At least 147 people are dead in Chile following the 8.8 magnitude quake. After the earthquake, a tsunami warning was issued and a wave measuring 2.34 metres was measured in Talcahuano, Chile. Later in the morning a wave of 0.35 metres was measured at Easter Island.
A tsunami advisory is in effect for California, and other areas along the West Coast are taking precautions. Hawaii is currently making plans to evacuate its residents, and as a result, the port of Honolulu has been closed.
Overnight New Zealand Civil Defence had predicted waves of between one and three metres for the Chatham Islands (800km east of the NZ mainland) and Banks Peninsula on the South Island.
However the first wave to arrive in New Zealand reached the Chatham Islands at approximately 7am. (but wave surge high of only 20cm (8') arrived.
Waiting to hear what happens in the Chathams with particular concern, was the Civil Defence in Canterbury.
Residents in low lying areas in Banks Peninsula had been told to be prepared to evacuate, if Tsunami waves in the Chatham had been of significance..
Most of the east coast is expected to see waves of less than one metre.
In the North Island North Cape, Whangarei, Auckland, Mt Maunganui, East Cape, Gisborne, New Plymouth, Napier, Wanganui and Wellington are affected.
And in the south, the waves are expected to hit Nelson, Marlborough Sounds, Westport, Greymouth, Christchurch, Timaru, Milford Sound, Dunedin, Bluff and Stewart Island.
NZ Civil Defence acting director Alan Walker says although one metre does not sound like a lot, there is still potential for damage.
'Remember that is wave height and it depends on the tides and it also depends on the run up that may occur. So it is possible that we will get some sort of marine damage.'
Unlike a swell of a metre which forms a wave and then dissipates on a beach, a tsunami swell of a metre can have a wall, or plateau, of water behind it. It is this momentum that can see the surge extend inland.
In the last few minutes Australian BOM officials have warned that waves could be largest up to six to 12 hours after the first arrivals and strong currents and unusual tidal effects may continue for many hours.
Police services have asked residents NOT to head to beaches to sight-see.
by Sail-World & wire services
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