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Home > Latest News > Media Releases > Media Releases 2011 > March 2011 > Tsunami threat to New Zealand Marine threat confirmed 3

Tsunami threat to New Zealand Marine threat confirmed 3

Friday, 11 March 2011 11:30 p.m.

A tsunami marine warning is in effect for New Zealand:

The tsunami warning will remain in effect until a cancellation message is issued by MCDEM.
An earthquake has occurred with these parameters:
Origin time: 0545Z 11 March 2011
NZ time: 1846NZDT 11 March 2011
Co-ordinates: 38.2 North 142.5 East
Depth:  24km
Location: Near East Coast of Honshu, Japan
Magnitude:  8.9
The above magnitude is provisional and may be increased or decreased as more seismic data becomes available. 
Bay of Plenty Civil Defence Emergency Management Group has activated and is monitoring the situation.

The Pacific Tsunami Warning Centre (PTWC) has issued a Tsunami Warning for New Zealand in response to the above earthquake. The New Zealand Tsunami Expert Panel assessment is that there is a marine threat only for New Zealand.  A marine threat means strong and unusual currents are possible in the sea, river mouths and estuaries, and unusual wave activity is possible at the beach.  No land threat is expected at this time. 

Historical events and pre-calculated tsunami models indicate that the largest effects (less than 1m wave height at the coastline) is expected along the coasts of the central and northern North Island (i.e. from East Cape northwards and from Kaipara northwards).   First arrivals in the upper North Island are expected to coincide with a low tide. 

Confirmation been received that a tsunami was generated.  Wave heights of up to 4 metres have been measured in coastal Japan.

The first wave to arrive to New Zealand will be in the area around North Cape at approximately 0623NZDT 12 March 2011. The first wave may arrive later and may not be the largest. Tsunami activity such as unusual currents and changes in sea-level will continue for several hours.

People in coastal areas should:

1. Stay off beaches
2. Stay out of the water (sea, rivers and estuaries, including boating activities)
3. Do not go sightseeing
4. Share this information with family, neighbours and friends
5. Listen to the radio and/or TV for updates
6. Follow instructions of your local Civil Defence authorities.

MCDEM and scientific advisors are closely monitoring the situation to determine the severity of the threat to New Zealand.

Bay of Plenty Civil Defence Emergency Management Group information
The expected arrival time in the Bay of Plenty is about 7.20am
The Whakatāne River Bar has been declared unworkable.


For more media information please contact Bronwyn Campbell, Public Information Manager on 021 287 9380.