20 MAY 2008
New gauge part of tsunami monitoring network
A sea-level gauge installed at the Port of Tauranga this week will form part of a national network of gauges for
monitoring tsunamis, Land Information New Zealand (LINZ) and GNS Science announced today.
The Tauranga installation is the fifth in a planned network of gauges at 20 sites around New Zealand.
Five gauges will be on offshore islands, with the rest at coastal locations. LINZ is overseeing the project in
partnership with GNS Science, which is installing and operating the network (scheduled for completion in 2010).
The gauge in Tauranga is being attached to an underwater pile on the tug boat berth. Sensors inside the gauge measure
changes in water pressure which relate directly to the wave height above the instruments.
“The gauges at coastal locations such as Tauranga will detect first landfall of tsunami waves,” said LINZ’s Manager
Geodesy Graeme Blick.
“They will also enable an ‘all-clear’ to be given if a large undersea earthquake has not produced a tsunami, or if a
near-shore earthquake has generated only a small wave.”
The instruments on offshore islands will give information about the size and possible arrival times of incoming tsunamis
from distance sources.
Instruments in the network send continuous data by radio to GNS Science in Lower Hutt where the wave height information
is freely available through the GeoNet website.
In the event of a tsunami reaching the coast, information from the network will be provided promptly to New Zealand
civil defence agencies so they can focus their response on areas that have been affected most.
Director of the GeoNet Project at GNS Science, Ken Gledhill, said the sea-level measuring network was an important part
of a tsunami monitoring system that consisted of seismology, sea-level measurements, computer modelling, and historical
information on seafloor earthquakes.
“Tsunami are an important international issue, and this network will contribute to the international effort to provide
tsunami warning around the Pacific,” Dr Gledhill said.
The information the network records will be shared in real time with tsunami warning centres around the Pacific.
A panel of specialists from the National Institute of Water & Atmospheric Research, the University of Waikato, LINZ, and GNS Science chose the locations for the gauges.
ENDS