February 28, 2005
Business Journal

Papers obtained by the Dominion Post under the Official Information Act show the Cabinet is concerned about New Zealand's vulnerability to tsunamis -- despite a long history of public pronouncements that all was well.

The government has long maintained that warning systems for tsunamis originating from close-in seismic events would make little difference in human costs -- despite strong evidence to the contrary from the US and Japan.

More, it has maintained that New Zealand would receive adequate warning about trans-Pacific tsunamis -- of the type most catastrophically demonstrated by the Boxing Day tsunami -- from the US deep ocean tsunami warning system. That system, it was revealed after the Boxing Day tsunami, has been in extreme disrepair for years and is only now being fixed up.

But worse, it contains only a single detection station, parked in the ocean off the north-west corner of South America and could not detect or warn about mid-ocean seismic events.

According to the DPost, officials have been told to report by September on ways of managing these and other risks.

Meantime, the global tsunami warning system envisioned in the wake of the Boxing Day tsunami has sputtered out under UN leadership, resolving into a series of mostly minor nationalistic initiatives.

Australia and the US -- both of which went into the global planning meetings with their own initiatives well under way -- now look to be the big guarantors of warnings to New Zealand, as each is undertaking massive, interoperable efforts to establish warning systems in far flung networks.

At home, early emphasis appears to be collecting around the neglected GeoNet project, which has fallen short of meeting its goals -- seismic monitoring inside the country -- by $25 million. Fully funded, that project would considerably enhance New Zealand's ability to monitor earthquakes, but it is not envisioned as a tsunami prediction and warning tool.


AN OLD STORY, GETTING OLDER BY THE MINUTE

As NBR Online noted on 10 January, the dangers of tsunamis to New Zealand has been well established for a very long time.

According to a June 2001 hazard scoping report prepared for the Wellington Regional Council, New Zealand is at risk from trans-Pacific tsunamis to about the same degree as Indonesia and Hawaii -- and the likelihood that a trans-Pacific tsunami will strike New Zealand soon is high.

Yet New Zealand depends almost entirely for warning about trans-Pacific tsunamis on a system that concentrates on the North Pacific, much like Indonesia, Thailand and the other countries hit by the Boxing Day tsunami.

At best, scientists say, the warning systems in place now might alert authorities that a tsunami was underway -- but they could not predict its likely impact on arrival.

In all of this, the government's response has been much like that of Indonesia, which had a plan on its books to develop a tsunami warning system that would focus on threats from the Indian Ocean, but did not move quickly enough.

Here, the implementation of an adequate detection and warning system -- one the government agreed to in 2001 -- has been short-funded by an essential few million a year, largely because the project has jobbed out to a patchy network of historically indifferent sponsors.


FRONTING UP, ALMOST

Just before leaving for Thursday's tsunami summit in Jakarta, Prime Minister Helen Clark appeared to front up to the media about the inadequacy of New Zealand's tsunami warning system, saying coverage was inadequate and needed upgrading.

But Miss Clark was speaking about coverage gaps in the southwest area of New Zealand going into the Southern Ocean, the same area that was hit by an 8.1 (Richter) earthquake north of Macquarie Island in the south Tasman Sea on 23 December.

Like most earthquakes at sea, regardless of magnitude, the 23 December event, a "strike-slip" quake in which opposing tectonic plates moved horizontally rather than vertically, did not generate a tsunami -- but it did generate a warning from the National Oceanic and Atmospheric Administration (NOAA) Pacific Tsunami Warning Center (PTWC). Issued 20 minutes after the quake began, that warning noted "this earthquake has the potential to generate a widely destructive tsunami in the sea near the earthquake" and advised local authorities to be aware of the possibility.


ALPHABET SOUP, UN STYLE, AND A SIMPLE FACT

Much of the science needed for tsunami warnings exists -- and much of its development is in the hands of a very tangled bureaucracy.

The PTWC informs the International Coordination Group for the Tsunami Warning System in the Pacific (ICG/ITSU), to which New Zealand belongs.

According to the NOAA, the main purpose of the group is to assure that tsunami watches, warning and advisory bulletins are disseminated throughout the Pacific to its 28 member states "in accordance with procedures outlined in the Communication Plan for the Tsunami Warning System. The ICG/ITSU is a subsidiary body of the United Nations Educational, Scientific, and Cultural Organization, Intergovernmental Oceanographic Commission (UNESCO/IOC)" -- and operates at a level of bureaucratic richness that typifies most UN operations.

The group has been moving at glacial speed toward developing a more effective tsunami warning system for the South Pacific, but has made little real progress.

At a July meeting of the Southwest Pacific and Indian Ocean Tsunami Warning System (SWPIO TWS) Working Group, for example, a meeting attended by New Zealand, Dr Phil Cummins of Geoscience Australia advanced a proposal for a relatively simple system, using existing seismic and ocean monitoring networks, that would give member nations -- including New Zealand -- an effective, Number 8 wire pilot system that might be expanded if it proved successful.

The proposal "generated much interest," according to the minutes of the meeting and was promptly spun out into a committee for development.

"The Workshop Recommendations are being presented for further discussion at the SOPAC STAR meeting, where a STAR Tsunami Working Group will be co-convened by Laura Kong and Atu Kaloumaira to receive further input and formulate Recommendations that will be put forth by the STAR Chair to the SOPAC General Council for acceptance. Once accepted, they can then become officially part of the SOPAC Work Programme and receive funding if a high priority," the minutes recount.

Working efficiently along in the background, however, the PTWC is the agency responsible for actually issuing most of the tsunami warnings that affect the Pacific -- and it is the agency Miss Clark said did not adequately cover the area referenced in the warning.

The "coverage gap" in the Southern Ocean is actually not about seismic monitoring -- although most agencies involved in seismic research say local detail enhances global data -- but the much more fraught problem of making sense of seismic activity.

The action gap, however, seems to be the result of an elaborate committee process typical of United Nations undertakings -- and, on a parochial level, a shortfall in local funding by the New Zealand government..


READING WARNINGS

Collecting and analyzing seismic data is part one of a two-step process in generating high-quality tsunami warnings. The second step involves collecting and analyzing data about the sea itself -- and it is in this second step that the greatest vulnerability exists.


SEISMIC: GEONET

New Zealand's local system of seismic detection and warning is operated by GeoNet, a program that took over the responsibility in 2001. GeoNet's instrumentation and analysis capabilities are being upgraded as part of a ten year plan that kicked off when it was formed.

GeoNet is 60 per cent funded by the Earthquake Commission (EQC) which has a commitment to the programme of $5 million a year through 2011. The balance, GeoNet says, is to come from "other national and regional organizations" including the EQC's partners in the project, the Institute of Geological & Nuclear Sciences (which operates and maintains the equipment) and the Foundation for Research, Science & Technology.

That support has not fully materialized -- in large part because local bodies have not contributed.

Should that shortfall be cause for concern?

All important global seismic activity is registered in several international centres and resulting data -- including tsunami warnings -- are already available for the taking.

The US Geological Survey (USGS), for example, can make initial global determinations of location and magnitude within 90 seconds, broadcast information about the earthquake to registered pager numbers within 3 minutes and 20 seconds, place the information on the internet within 4 minutes and produce an internet-accessible activity map in less than 5 minutes.

Initial tsunami warnings from most global seismic monitoring stations -- such as the ones sent out automatically following the Boxing Day earthquake -- are based only on the magnitude and location of an earthquake.

One important data source often overlooked is the near-real-time steam from the Comprehensive Test Ban Treaty Organisation (CTBTO), which maintains an enormously sophisticated global system of seismic sensors. CTBTO data can arrive even more rapidly than PTWC seismic data -- and is at least as accurate -- but both require skilled technicians at the receiving end and neither can alone predict or describe a tsunami. GeoNet was specifically designed to utilize that data.

But seismic data don't really have much to say about tsunamis, other than that they may have formed.

Since Hawaii's Pacific Tsunami Warning Center was established in 1948, in fact, about 75 per cent of seismometer-generated warnings that resulted in evacuations turned out to be false alarms, according to a Public Broadcasting Service (PBS) documentary on the subject.

One indication of the danger in relying on purely seismic data to predict tsunamis comes from the website of the Institute of Geological & Nuclear Sciences in a press release about a 7.2 magnitude earthquake on 23 November 2004. That quake, which occurred under the sea southwest of Invercargill, measured 7.2 and was located only 100km off the southern Fiordland coast at a depth of 33km and was felt as far north as Auckland. The Institute noted that such a quake could have caused a tsunami, but the "absence of a tsunami at Bluff indicates that there was no substantial vertical movement of the ocean floor at the epicentre," the Institute said.

Had Bluff been wiped out by a wall of water, presumably that would have indicated that the quake had demonstrated 'substantial vertical movement.'


OCEAN: NIWA

The sea-based technology in New Zealand's tsunami warning system is currently under the administration of the National Institute of Water & Atmospheric Research (NIWA), again in partnership with the Institute of Geological & Nuclear Sciences. The specific sub-agency within NIWA that deals with tsunamis is the Natural Hazards Centre.

There appears to be a widely-shared belief that New Zealand has a system of sea-based warning devices, but that is not the case.

The GeoNet project was to have developed both a comprehensive network of tsunami detectors and the skilled scientists necessary to use them, but a funding shortfall of $25 million shelved that aspect of the project.

Other funding shortfalls have seen the buildup of GeoNet's seismic system slowed, according to press reports, but tsunamis are spawned by seismic events that existing systems could not miss.

Earthquake commission general manager David Middleton told the Dominion Post that the EQC would review funding for the tsunami system later this month with a renewed sense of urgency.

Mr Middleton said local and regional councils -- on which funding for much of the GeoNet and NIWA system development is reliant -- had been "unable" to contribute..

NIWA does "coordinate" a network of open coast sea-level recorders around the New Zealand coast -- the sea-level recorder network -- and says that "some of the recorders have also been tsunami enabled to store sea-level measurements quickly at 1-minute intervals to better describe the various waves that make up a tsunami event."

Not detect, not warn, but describe.

The network is "supported by some regional and district councils, University of Canterbury and by the National Tidal Facility (Adelaide)," NIWA says and its primary purpose is to assess whether global warming is having an effect on sea levels.

NIWA is candid about this gap in its capacity and says:

Pacific-wide warnings can in most cases be processed by the Ministry of Civil Defence & Emergency Management many hours in advance via the Pacific Tsunami Warning Center in Hawaii. However, these warnings give arrival times IF a tsunami has been generated, but have no way of estimating the size of the wave. This is a research need recognised in our programme.

When it comes to tsunamis generated by local phenomena such as earthquakes and/or underwater landslides or volcanoes along plate subduction zones off eastern New Zealand and south-west of South Island, NIWA says "little warning is possible" and concentrates its research not on providing what might be precious moments of warning within that narrow window of time, but on efforts to pinpoint "geological features like previous seabed slumping, landslides and faulting on the ocean floor that may potentially cause a tsunami."

It aims through that research to model how and where local tsunami would propagate to the coast -- an outcome that might be useful for planners and insurers, but which will give little comfort to anyone in the path of such a wave.

Is it impractical to provide warning for locally generated tsunamis?

The EQC has said it wants such a network and the United States and Japan both monitor not only at the deep sea level, but closer in to shorelines, using special networks of bouys -- and maintain systems that might give local communities precious minutes of warning.

NOAA's Frank Gonzalez, who headed such a sensor project, said close-in monitoring buoys are better than nothing, according to a PBS documentary. "A minute or two of warning will get you down the road another half mile and you'll be safe," he said. During the 1993 tsunami attack on Okushiri, Japan, Mr Gonzalez said, "there were a number of incidences in which people were educated enough about tsunamis that they were out the door and up the hill in their pajamas within minutes of the warning, and it saved their lives."

THE DEEP BLUE SEA

Typically, the PTWC, once alerted by seismic sensors of earthquake activity, uses other technologies -- such as its Deep-ocean Assessment and Reporting of Tsunamis (DART) network -- to assess whether a tsunami has been spawned -- but the PTWC, and another American agency like it, are designed specifically to provide tsunami warnings for the west coast of the United States, Hawaii and Alaska.

Japan also uses sea-based sensors -- tsunamimeters and other devices -- to augment its seismometer network, but no agency has ocean-based technology in place to cover the Southern Ocean.

More critically, however, PTWC DART bouys are concentrated on the North American coastline, extending south only to the northern edge of South America -- thousands of miles north of the earthquake belt of most concern to New Zealand -- and even though their data is available in near-real-time through a variety of channels, including the internet, they are a northern hemisphere tool.

NEW ZEALAND HAS A HISTORY OF VULNERABILITY

The NIWA itself describes New Zealand as being situated in the open Pacific and very vulnerable to remote tsunami generated by earthquakes or underwater landslides along the Pacific Rim, from sources even as far afield as Alaska -- and, in light of recent events, from Antarctica and the Southern Ocean..

But tsunamis from South American sources probably pose the greatest "external" tsunami threat to New Zealand, NIWA says, and the country has been hit by tsunamis spawned off Peru and Chile.

Those tsunamis have not yet ever caused much damage, but tsunamis are shaped by myriad particulars, each unique, in addition to the power of their spawning event -- and as New Zealand increasingly populates its shoreline, the risks increase exponentially.

According to PBS, a critical variable is the shape of the beaching point for a tsunami as it makes landfall. "During the 1993 tsunami attack on Okushiri, Japan," PBS reported, "the wave 'runup' on the coast averaged about 15 to 20 meters (50 - 65 feet). But in one particular spot, the waves pushed into a V-shaped valley open to the sea, concentrating the water in a tighter and tighter space. In the end, the water ran up to 32 meters (90 feet) above sea level, about the height of an 8-story office building."

Here, almost all studies agree an important trans-Pacific tsunami strike is inevitable in the relatively near future.

The 2001 Wellington report appears to reiterate the findings of a 1997 report to the Otago Regional Council that said the east coast of the South Island had a 40 per cent chance of being hit in the next 50 years by a tsunami originating off South America -- the same earthquake zone that has spawned all four of the significant trans-Pacific tsunamis that have hit New Zealand in the last 140 years.

But more critical is the level of risk from large locally-generated tsunamis, as the 2001 Wellington report warned, cautioning that such events strike about once every 84 years -- and that the last occurrence was in 1947.

The largest of that type of tsunami hit the Wairarapa in 1855, with waves up to 10 m high, but local tsunamis in other countries have produced 100 m waves.

The largest of the trans-Pacific tsunamis to come ashore in New Zealand took place in 1868 and raised the sea by 2.4 m above normal high tide levels. Other South America spawned tsunamis hit the country in 1840, 1922 and 1960.


WARNINGS AREN'T ENOUGH

The 1960 tsunami was spawned by a magnitude 8.5 earthquake in southern Chile and resulted in no loss of life here but widespread minor damage to coastal facilities and small boats, raising sea levels by as much as 5.5 m in isolated spots such as Lyttelton Harbour.

According to the Natural Hazards Centre, thousands of people were evacuated from the impact path as the tsunami roared across the Pacific, making it the largest ever evacuation in New Zealand history. Yet one study found that despite warnings, many people actually went down to the sea to watch the incoming waves.


INSTALLING DART AND OTHER NEXT STEPS

In order to obtain detailed information about incoming tsunamis, New Zealand needs not only a network of perimeter bouys dedicated to detecting local tsunamis but a deep water warning network similar to the DART system used by the PTWC.

It already has access to strong seismic and its civil defence warning systems could be upgraded to the task far more easily than will be the case in Indonesia, India or Sri Lanka, where there is rampant bureaucratic chaos and only minimal technology on the ground.

A DART system (click for animation) consists of a seafloor bottom pressure recording (BPR) system capable of detecting tsunamis as small as 1 cm, and a moored surface buoy for real-time communications. An acoustic link is used to transmit data from the BPR on the seafloor to the surface buoy. The data are then relayed via a GOES satellite link to ground stations.

According to New Scientist, the cost of implementing such a warning system even for an area as vast as the Indian Ocean basin is relatively nominal.

Phil McFadden chief scientist at Geoscience Australia, which has been commissioned by the Australian government to design an early warning system for the Indian Ocean, told New Scientist an Indian Ocean warning system could consist of 30 seismographs to detect earthquakes, 10 tidal gauges and six DART buoys. He estimates that it would only cost around $US20m to install these sensors -- and other sources have pegged the cost of the DART buoys themselves at around $US250,000, with annual maintenance costs running around $US50,000 for each..

Whatever the cost and no matter how perfect the system, all experts agree that warnings, no matter how detailed and timely, are useless without adequate civil defence procedures -- and those fall to our Civil Defence Ministry, headed by Hon George Hawkins, which runs a 24-hour alert system that includes regional and district councils, the news media, government departments and the police communications centre.

According to Civil Defence NZ, when a tsunami warning is received, the Ministry for Civil Defence and Emergency Management "issues a national warning through the Police to Civil Defence organisations, and through nation-wide radio and television broadcasts." In the event the tsunami is the result of a local seismic event, "there won't be enough time to issue a warning," the agency says.

According to one interview with Civil Defence Ministry Readiness Manager, Mike O'Leary, the ministry's goal is only to get the word out.

People in the path of a tsunami would then, presumably, either evacuate themselves in an orderly manner -- or not.

As Civil Defence NZ puts it: "If you see the tsunami, it will be too late to escape."

28-Feb-2005
NBR

http://www.nbr.co.nz/home/column_article.asp?id=11455&cid=5&cname=Asia%20&%20Pacific