PAPUA NEW GUINEA
ISSUES FOR EMERGENCY MANAGEMENT IN THE SOUTHWEST PACIFIC REGION
GEOLOGICAL SURVEY OF PAPUA NEW GUINEA
AUSTRALIAN GEOLOGICAL SURVEY ORGANISATION
INTERNATIONAL ASSOCIATION FOR VOLCANOLOGY AND CHEMISTRY OF THE EARTHfS INTERIOR
COLLAPSES AND TSUNAMIS
Ulawun volcano is identified by International Association for Volcanology and Chemistry of the Earthfs Interior (IAVCEI) as one of 16 volcanoes world-wide for special study during the United Nationfs International Decade for Natural Disaster Reduction (IDNDR),1990-1999). Ulawun is the only Decade Volcano to have been nominated from the southwest Pacific region.. The Ulawun Decade Volcano Project is led by I. Itikarai and H. Patia of the Rabaul Volcanological Observatory which is part of the Geological Survey of Papua New Guinea in the PNG Department of Mineral Resources.
Box: Recommendations for Papua New Guinea, West New Britain and Ulawun Volcano
Box: Recommendations for the southwest Pacific region in general (Including Papua New Guinea)
Box: Aims of the Workshop
What are volcanic hazards?
Box: Principal volcanic hazards
What Happens when a volcano collapse?
Box: How volcanic cones collapse
What is hazardous about Ulawun volcano?
How widespread is the problem of volcanic cone collapse in the southwest Pacific?
Box: Historical cone collapse in the southwest Pacific
Box: Recommendations A: Future scientific study of Ulawun and other
unstable volcanoes in the southwest Pacific
How can volcanic cone collapse be monitored?
Box: Some techniques that may be useful in monitoring potential volcanic cone
How is Ulawun monitored?
Box: Recommendation B: Monitoring of Ulawun volcano
What is tsunamis?
How can tsunamis be understood?
Can coastal communities be protected from tsunamis?
Recommendations C: How to cope with tsunamis
What is emergency management?
Does Papua New Guinea need a Disaster Management Plan?
What are volcanic crises?
What is volcano-emergency planning?
1. Volcano alert system
2. Hazards and risk mapping
3. Education and awareness
4. Response planning
Box: Alert levels for Ulawun volcano
Box: Recommendations D: Volcanic Emergency Management
Appendix A: IAVCEI and the Decade Volcano Project
Volcanoes such as Ulawun in West New Britain Province, Papua New Guinea, are unstable mountains. Large parts of them may collapse from time-to-time forming giants rock slides that become dangerous avalanches. Destructive tsunamis may form where these volcanic avalanches enter ocean. The general problem of collapsing volcanic cones, volcanic activity, tsunamis, and emergency management was discussed at the international Decade Volcano Workshop where Ulawun was taken as a gcase studyh. The Workshop made 25 recommendations of local, national, and the regional scope (these are shown numbered in the main text of the report in four Tables A to D, and are reproduced on the next three pages as part of this Summary using the same coding system – e.g. A1, B1, B2, and so on). The Workshop proposed, for example, that identification and adequate monitoring the volcanoes capable collapsing should be undertaken throughout the southwest Pacific region and that their structure and underground magma systems should be studied fully. Furthermore, more research is required on the effects of the tsunamis that may result from cones collapse, although these can be predicted already to some extent from computer calculations. A project should be undertaken in West New Britain Province as a matter of urgency to map hazard zones, to identified communities, investment, and infrastructure that are at risk, and to make specific recommendations for risk mitigation. The proposal for a revision of the national Papua New Guinea Disaster Management Plan was strongly supported. The workshop also recognized that volcanically vulnerable areas throughout the southwest pacific region require volcanic emergency-management plans.
Recommendations for Papua New Guinea, West New Britain Province, and Ulawun Volcano:
A1. A specific project is required for Ulawun, aimed at reassessing the geology of the volcano, including its internal structure, and incorporating aspects of recommendations A2-A6 (that apply throughout the southwest Pacific), with view to better defining the hazard potential at Ulawun.
B1. A better understanding is required of the underground magma system of Ulawun, together with a detailed map of the geological structure of the volcano and the surroundings area (see Recommendations A1) so that the best monitoring network can be established.
B2. Funding is required for an enhanced, permanent, monitoring network involving more instruments (for earthquake and ground-deformation measurement) together with the commitment to the financing of future maintenance and operating costs.
B3. Instrumentation for a field network should be kept in reverse at the Rabaul Volcanological Observatory for rapid deployment to Ulawun in times of crisis, together with the funds available to finance installation at short notice.
B4. Collaborative projects on the remote sensing of Ulawun should be established between the Rabaul Volcanological Observatory and an institution having the appropriate technical capacity to obtain and analyze satellite images of the volcanoes.
C1. Tsunami modeling of the Kimbe Bay area should be carried out using gscenarioh collapse from Ulawun as the initiating event so as to establish the scale of the risk.
D1. A risk mapping project should be undertaken as a matter of urgency in West New Britain province in order to map hazard zones (e.g. for volcanic eruptions, earthquake, and tsunamis) to identified communities, investment, and infrastructure that are vulnerable, and to make specific recommendations for risk mitigation. Result should be fed into provincial government plans for emergency management response, economic development planning, and land-use strategies.
D6. The concept of the Papua New Guinea Disaster Management Project is strongly endorsed.
D7. The work of the Rabaul Volcanological Observatory as Papua New Guineafs primary source of volcano information and advice is strongly endorsed. National volcanological observatories have an important public-safety role to play. Observatories should be established in those volcanically active southwest pacific countries that do not already have them.
Recommendations for the Southwest Pacific region in general (including Papua New Guinea) :
A2. Analysis of the shape and geological structure of the Southwest Pacific volcanoes identified as having a high risk should be undertaken using satellite imagery.
A3. Geological studies aimed at determining the nature and distribution of past eruptions and unraveling the history of selected volcanoes in the southwest Pacific, aimed particularly at identifying past cone collapses and their products, are recommended.
A4. Programs aimed at providing further information on the ages and frequency of eruptions at unstable volcanoes by dating volcanic deposits in the laboratory using specialized isotopic methods, are required.
A5. Geotechnical analysis of volcanic products should be undertaken in order to provide data on the strength of the materials making up volcanic cones.
A6. Development of a computer modelling program is required to examine (a) different collapse scenario, and (b) the likely paths of hazards generated during such collapses.
C2. Education of at-risk populations throughout the southwest Pacific region is recommended so that they can react swiftly to warning of possible tsunamis, including those of the both volcanic cone collapse and earthquake origin. This can be initiated at little cost.
C3. A public awareness video on tsunamis should be produced for viewing throughout the southwest Pacific region.
C4. A list of coastal, submarine, and island volcanoes in the southwest Pacific region should be compiled. This should include details on the potential for collapse and the possible volumes of collapsed materials that may be involved.
C5. Detailed bathymetry is needed, not only near potential volcanoes-collapse site, but also at potential landfall areas for tsunamis of different origins, including those caused by earthquakes. This might be completed initially for coastlines facing the deep-sea trenches of Papua New Guinea, and than could be used to prioritize the most hazardous areas and to generate risk maps (see below). Results also would provide a database for the required modelling.
C6. Coastal studies at potential tsunami landfall areas should be undertaken. Mapping of surface deposits and geomorphology would be useful in identifying past tsunamis deposits and the resulting data could be added to models of tsunami behaviour.
C7. A program of inundation modeling needs to be initiated, addressing the magnitudes and geometries of tsunamis that may be produced by volcanoes collapses of different sizes into water with seafloor at different morphology.
D2. Volcanically vulnerable areas require development of specific emergency-management plans. These plans must be (1) identify the responsibilities and the role of all emergency-management agencies involved in a crisis, (2) allow for training, and (3) be exercised regularly in order to test their effectiveness.
D3. All initiatives aimed at improving the efficiency of communication systems among emergency-management agencies are strongly supported. Effectiveness linkages must be established between all relevant agencies involved in the responses to a volcanic crisis.
D4. Education and awareness plans for active volcanoes and volcanic eruptions need to be established and promoted throughout the southwest Pacific region. The IAVCEI videos (gUnderstanding volcanic hazardsh and gReducing volcanic riskh) should be reproduced in the Tok Pisin language for use in Papua New Guinea, Solomon Island, and Vanuatu.
D5 Volcano alert systems should be developed for areas of volcanic risk throughout the southwest Pacific region in order to act as a baseline for emergency management decisions. Volcano alert levels should be determined by volcanological observatories having the appropriate monitoring and administration systems to undertake this tasks and in conjunction with local authorities.
D8. Attention should be given to the establishment of rapid-deployment scientific teams who have prior approval to investigate affected areas. Appropriate mechanisms should be put in place also to screen requests from the international community seeking permission to investigate disaster areas.
Active volcanoes are common throughout the nations of the southwest Pacific region. Volcanoes are unstable structures. Large sections of them can detach and collapse catastrophically creating debris avalanches (definitions of some technical terms are given in the boxes entitled Glossary and Principal Volcanic hazards). Giant sea waves or tsunamis may form where the debris avalanches crash into ocean. These high-energy waves can travel great distances and caused destruction on coastlines both nearby and far from the volcano that produced the debris avalanches.
An international workshop designed to focus on the problem of volcanic cone collapse and tsunamis was held at Walindi, West New Britain Province, Papua New Guinea, between 28 September and 3 October 1998 (see Appendix B). Ulawun was chosen for the workshop because it its exceptionally high and steep and because there is geological evidence that it may have collapsed catastrophically in the past, possibly causing damaging tsunamis along the Bismarck Sea Coastline.
The Ulawun Workshop happened to take place shortly after the disastrous 17 July 1998 tsunami at Sissano Lagoon, near Aitape, about 970 kilometers to the west of Walaindi. More than 2000 lives were lost. This tragic event led to a particular focus at the Workshop on the vulnerability to tsunamis of populations living in the coastal parts of West New Britain, especially the shores of Kimbe Bay above which Ulawun rises dramatically.
l Discuss and assess the implications of volcano collapse for disaster management throughout the southwest Pacific region.
l Foster interest amongst the international volcanological community in the prediction and assessment of impact of catastrophic gravitational collapse of southwest Pacific volcanoes, including tsunami generation.
l Encourage interaction between international experts on volcano collapse and tsunami generations and Pacific Island scientists and emergency managers.
l Focus attention on Ulawun volcano: how to forecast collapse events there, and to determine what the effects would be of debris avalanches entering the Bismarck Sea.
Papua New Guinea localities mentioned in the text
(see gPrincipal Volcanic Hazardsh box for further definitions)
Large open-ended depression on a volcanic cone formed by collapse of part of the cone
A bowl or funnel-shaped depression, generally in top of volcanic cone (hence gsummit craterh). Crater are less than about 2 kilometers across.
Geographic Information System : computer systems that hold much information that can be used to make many different types of maps and to answer quickly questions relating to the geographic distribution of people, agriculture, land types, village, hazards, and so on
A hot silicate liquid formed where rocks deep in the Earth are melted – in other words, rock that has become molten.
Magma that flows out of a volcano onto the surface of the Earth
Rabaul Volcanologists Observatory
Volcanoes whose general shape is that of a cone and which formed normally by eruption from a single, central crater
Volcanic hazards are threatening event that are associated with volcanoes whether the volcanoes are in eruption or not. Volcanic hazards can cause injury, loss of live, and damage to property and agricultural lands. There are different kinds of volcanic hazards and these can differ from one volcano to the next. Some volcanoes produce mainly relatively gquiteh flows of lava. Others explode violently, hurling ash and debris to great heights which fall over large areas. The nature of the hazards depends on many factors, especially the viscosity or gstickinessh and gas content of the magma, the time since the last eruption, how big or steep the volcano is, and event the kind of climate of the region where the volcano is located.
Principal Volcanic hazards
Pyroclastic flows : These are the most dangerous volcanic hazard. They consist of mixture of superheated volcanic gases and hot ash and blocks. Pyroclastic flows are generated during larger explosive eruptions. They travel down the flanks of the volcano at speeds in excess of 100 kilometers per hour and temperatures of up to 8000C, and destroy everything in their paths. Deaths is from burning and asphyxiation.
Debris avalanches, * parts of volcanoes may collapse to form a rock slide and then an avalanches that can travel dowmslope at speed greater than 100 kilometers an hour. Small landslides will be confined to valleys and may not travel far from the volcano. But much bigger rock slides may form if a large parts of volcanic cone collapses. This can produce debris avalanches that represent on of the most dangerous of all volcanic hazards. They can cause tsunamis if they enter the water. These hazards were the main topics of the Ulawun workshop.
Mudflows or glaharsh : Lahar is an Indonesian word for the volcanic gmudflowh. These are generated where heavy rains mix with volcanic materials (not just mud) or where an eruption takes places in a lake or onto snow and ice. The mixtures of rock, soil, and water can travel down slope at speed of 50 kilometers an hour or more, and cause major loss of life and damage property. Lahars usually are confined to valleys, although they may spread out considerably when they reach flatter terrain.
Tsunamis: Waves in the oceans, sea, or lake, formed generally as a result of underwater earthquakes, submarine volcanoes, or undersea landslides, or avalanches into water, or bay the impact of meteorites from space.
Earthquake: Vibration and shaking of the surface of the Earth caused when the rock within the Earth breaks and sends out 2wavesh of energy. The ground surface may be fractured by some earthquake forming cracks, and fissures. Earthquakes are formed (1) by large movements of the Earthfs crust (gtectonich earthquakes) and (2) where magma pushes up towards the surface beneath volcanoes (volcanic earthquake).
Volcanic gases: Volcanoes can expel gases even when they are not in the eruption. Gases can cause deaths by asphyxiation where their concentrations are high enough. For example, carbon dioxide is heavier than air, is colorless and has no smell, so flowing carbon dioxide can overwhelm and kill unsuspecting people.
Ashfall: Magma erupting explosively from volcano is ripped apart forming pieces that cool off and fall back as gashh. Particles of ash may be carried high – sometimes 40 kilometers or more – into the atmosphere. It settles over the surrounding countryside forming deposits that may be meters thick in the larger eruptions. Even a few tens of centimeters of ash can caused the collapse of poorly-constructed buildings, especially if the ash is wet. Ash may also cause collapse of power and telephones lines, limit road travel, clog the engines of jet aircraft, damage crops, contaminate water, and effect human health.
Lava flows: Generally slow moving ( a few kilometers per hour) griversh of lava (magma extruded onto Earthfs surface) that may erupted from the summit or flanks of a volcano. Lava flows are not usually a danger to life, but they can bury gardens and plantations and can cause a major damage to building and roads through their high temperatures (sometimes in excess of 1000 0C) and physical force.
Some common volcanic hazards
What happens when a volcano collapse
Large volcanoes that have grown over a long time are generally unstable. Some may collapse more than once in their lifetimes. A volcano can become unstable and then collapse for numerous reasons. Many volcanoes contain a high proportion of weak materials such as ash, fragmental materials, and a fractured lava flows which, combined which commonly steep slopes, make them susceptible to collapse. Volcanoes may be weakened by hot fluids (for example, acidic waters) within them that turn hard rock into soft clay. Debris avalanches are able to move quickly and for great distances because of the fractured nature of the rocks that make up the volcano and the presence of volcanic fluids and gas. Instability also can be increased by environmental factors such as heavy rainfall, erosion of the base of the volcano; a major earthquake shaking the volcano (ground shaking associated with the earthquake may cause collapse with little or no warning); tilting of the surface on which volcano is built; or eruption of new materials onto already unstable flanks. Probably the most common cause of cone collapse involves the intrusion of magma into the volcano providing the mechanical gpushh outwards, or else the magma heats up the water trapped in the surrounding rock deep in the volcano so that the resulting pressure increase causes part of the volcano to detach itself.
Collapse on volcanoes have a range of sizes from small, low-volume events such as rock falls, through medium-sized landslides, to the collapse of a large section of the volcano to form a debris avalanche. Large debris avalanches or glateral collapsesh can have volumes ranging from around 1 cubic kilometers to over 1000 cubic kilometers, and may start off as large rock slides, turn into debris avalanches, and then form mudflows.
The sequence of events that can take place when a volcanic cone collapses
A fresh body of magma intruding the volcanic cone cause the collapse of the cone and may itself become exposed at the surface when the collapse take place. The magma then explodes violently, causing a blast that can destroy everything within twenty kilometers or more. This blast is commonly accompanied by the entire range of volcanic hazards, including pyroclastic flows, extensive ashfall, and mudflows. A giants wave or tsunami may cause further devastation if the collapse volcanic cone or pyroclastic flows into the ocean.
Large collapses on volcanoes typically form arc-shaped cliffs that face the direction in which the rockslides and debris avalanche have slide away. The cliffs are called avalanche amphitheaters because they typically are open at one end. Some avalanche amphitheaters are U-shape in plan, other more spoon-shaped. The orientations and shapes of some avalanche amphitheaters are controlled by major geological structures in the region containing the volcano and may be quite straight, as on Ulawun volcano, as knowledge about previous collapses helps forecast future risks, such as at Ulawun.
How Volcanic Cones Collapse
l Injection of magma into the interior of the volcano causes the volcanic cones to inflate and the magma pushes out part of the volcano. Magma filling steep faults and fractures can provide a lubricated surface along which collapse may take place.
l The pressure of spaces (gpore pressure) within a volcano may increase owing to the presence of intruding magma, the volcano being squeezed by geological (tectonic) stresses, extra water within the volcano caused by increased rainfall, or a change in the local drainage system.
l Earthquake that gshakeh the volcano.
l Weakening of the volcano caused by heat and hot fluids in the interior of the volcano that alter hard volcanic rocks to soft clays.
l Slippage along the surface on which the volcano is built, caused by a low-angle fault or lubricants such as clays or injected magma.
l The volcano becomes too steep and high. Regular volcanic eruptions pile more and more volcanic materials onto the upper slopes of the volcano which then is susceptible to collapse through gravity..
Ulawun is the highest volcano (about 23000 meters above sea levels.) in the West New Britain Province. It is very steep-sided (about 350 at the top); is made up of a weak mixture of lava flows, volcanic ash, and other rock materials; and is frequently in eruption. Ulawun may have experienced a major lateral collapse in geologically recent times, as seen by large, north-facing cliff across the southern flank of Ulawun. The east-west direction of the cliff may be controlled by the faults observed in this part West New Britain. The cliff may represent the remnant of sudden, catastrophic, cone collapse, but the possibility cannot be excluded that collapse took place slowly and that the old volcano is buried beneath the present-day young cone..
The written record of historical volcanic activity at Ulawun starts in 1700 A.D. but is fairly complete only since 1898 A.D. Most historical eruptions have taken place from the crater at the summit of the volcano. The most common hazard at Ulawun over the past hundred years has been pyroclastic flows, which have been generated on six or seven occasions. Some damaged to property or crops took place four times as the flows traveled up to eight kilometers from the summit of the volcano. There have also been five eruptions during which ashfalls have been significant. Most notably in 1915 when up to 10 centimeters of ash fell as much as 50 kilometers away, causing buildings to collapse. Lava flows have been produced on at least five occasions, although no damage was recorded.
The historical record of eruptions at Ulawun is short, and so other potential hazards that may be associated with the future eruption must be considered. These include (1) mudflows (lahars) that may be generated if, for example, monsoonal rains fall on newly-deposited and unconsolidated ash, (2) relatively small-scale rock avalanches caused by eruption on the upper flanks, and (3) a large-scale lateral collapse caused by excessive steepness and structure of the volcano.
There is evidence of an east-west aligned structure cutting through the volcano that may mark a common path for magma. In particular, an eruption in 1978 produced lava flows from a fracture low on the eastern flanks of the volcano. This fracture points back towards the summit crater and may represent a major weakness in the present- day cone of Ulawun. A future collapse might take place either to the north, east, or west, in response to the gpushh of magma following this route. Involvement of magma in the collapse could lead to a full spectrum of volcanic hazards, causing total devastation of the area in the direction of the collapse. If this direction were the north, then the potential exists for a tsunami capable of threatening much the coast of West New Britain Province and the beyond (see below). However, there is at present no evidence for large-scale lateral collapse of Ulawun volcano taking place in the near futureB
How widespread is the problem of volcanic cone collapse in the southwest Pacific.
Many southwest Pacific countries consists of a volcanic island archipelago straddling the boundary between the large Pacific and Australian gplatesh of the Earth`s crust. Active volcanoes and earthquakes are common along this boundary. Only during the last two decades or so has there been appreciation of how volcanic cones can become unstable and collapse into the sea to produce tsunamis that may be highly destructive over considerable distances. The southwest Pacific region may have one of the highest probabilities of such events happening because of the proximity of several unstable volcanoes to the oceans. There are many historically active volcanoes within a marine environment in the region, so there is concern that more tsunamis will be generated in the future.
There have been six major lateral collapses of volcanoes in the recent times in the southwest Pacific, three of which have involved loss a life. The landslides created by collapses on two occasions generated tsunamis that resulted in major loss of life. Many ancient examples are known from New Zealand, Papua New Guinea, the Solomon Island, and Vanuatu, and Tonga.
Two other important examples of volcanoes producing devastating tsunamis are from Japan and Indonesia. The first of these was 1792 A.D. near Unzen volcano, Japan, where the volcanic cone of Mayuyama collapsed and a debris avalanche entered the sea forming a tsunami that killed more than 15,000 people. More than 36,000 people were killed in Indonesia during the famous 1883 eruption at Krakatau when pyroclastic flows were dumped into the Ocean forming destructive tsunamis.
Tinakula volcano and its avalanches amphitheatre, Solomon Islands, as seen from the air.(Photograph by T. Toba)
Historical cone collapses in the southwest Pacific.
Ritter (Papua New Guinea) 1888. Major cone collapse without signs of volcanic eruptions led the formation of a tsunami 12-15 meters high on nearby islands. An early missionary map shows the positions of villages in the western New Britain that no longer exist. Several hundred people were probably killed.
Ambae (Vanuatu) 1913. A lateral collapse after a large earthquake generated a landslide that caused possibly about 50 deaths.
White Island (New Zealand) 1914. This volcano located 48 kilometers offshore from the North island has a horse-shoe shaped crater just above sea level. Part of the crater rim collapse along a fault on or about 10 September and fell to the crater floor. There were 11 fatalities. No tsunamis were reported.
Ruapehu ( New Zealand) 1953. The upper portion of Reapehu`s crater wall failed on Christmas Eve releasing more than 1 million cubic meters of Crater Lake waters. The collapse was relatively small but resulted in a devastating lahar that swept away a railway bridge as main Wellington-Auckland express train was crossing and 151 lives were lost in what has known as the Tangiwai Disaster.
Tinakula (Solomon Islands) 1966. A landslide of unknown cause slipped into the sea from the high wall of an ancient avalanche amphitheater. They may have been tsunami but no lives were lost.
Lopevi (Vanuatu) 1975. A landslide associated with a lava flow from the summit crater plunged into the sea. No tsunami was recorded but the residents have now been permanently evacuated
Recommendations A : A Future Scientific study of Ulawun and other unstable volcanoes in the southwest Pacific.
1. A specific project is required for Ulawun, aimed at reassessing the geology of the volcano, including its internal structure, and incorporating aspects of the following recommendations (that apply through the southwest Pacific), with a view to better defining the hazards potential at Ulawun.
2. Analysis of the shape and geological structure of southwest Pacific volcanoes identified as having a high risk should be undertaken using satellite imagery.
3. Geological studies aimed at determining the nature band distribution of past eruptions and unraveling the history of selected volcanoes in the southwest Pacific, aimed particularly at identifying past cone collapses and their products, are recommended.
4. Programs aimed at providing further information on the ages and frequency of eruptions at unstable volcanoes by dating volcanic deposits in the laboratory using specialized isotopic methods, are required.
5. Geotechnical analysis of volcanic products should be undertaken in order to provide data on the strength of the materials making up volcanic cones.
6. Development of computer modelling program is required to examine (a) different collapse scenarios, and (b) the likely paths of hazards generated during such collapses.
How can volcanic cone collapses be monitored?
Volcanic cone may collapse in different ways (see above) and early-warning signs of collapse can be expected for most of these collapse mechanisms. Monitoring for potential volcanic cone collapses is essentially the same as monitoring for eruptions and is possible using instruments, as discussed below, but most of these methods are expensive and time consuming. Many volcanoes in the southwest Pacific region are not monitored because there is simply no money available to purchase monitoring equipment and to support the required scientific staff. The volcanoes in other cases may be isolated places where there are no people at risk, and so there is little apparent need to monitored the volcanoes. Investment in monitoring equipment requires a prior assessment of what is at risk, whether monitoring equipment is required, and what type of equipment is needed and can be afforded.
The most reliable information about events immediately prior to collapse may be gained from a dedicated human observer. A local observer in the field perhaps equipped only with the binoculars and camera, can report effectively on early-warning signs such as earth movements (fissures, cracks, minor landslips, and so forth); the presence of new hot ground and volcanic vapour; the presence of volcanic gas emerging from new vents; noises from ground cracking or explosions; red glow at night; and local earthquakes. A local observer can also pass on information from the general population to a appropriate authorities.
Potential volcanic cone collapse can be monitored by using different type of scientific instruments, such as following:
Seismographs can record earthquakes that may take place before a major collapse. The patterns of earthquakes may concentrate along zone where a latter cone collapse could take place. Earthquakes that take place before cone collapse (and volcanic eruptions in general) may be too small to be felt by people, but can be detected easily by seismographs. Seismographs also can used to determine the kinds of earthquakes taking place. This tells volcanologist something about what happen inside the volcano. Seismographs, therefore, is much like a doctorfs stethoscope in the way it is used to diagnose the gsoundsh produced within a volcano.
Ground Movements caused by both magma movements and volcano instability can be measured by a range of surveying instruments. The design of monitoring network can be determined by the type of movements expected, although the terrain usually determines where instruments can be placed. Different techniques can be used to measured the movements, but the technique employed in practice are often determined by cost.
A volcano can break into eruption quite quickly, so ideally signals recorded by instrument at a volcano should be sent directly by radio, telephone lines, or satellite links to an observatory staffed by trained volcanologists. This so-called greal timeh transfer of signals permits enough time to analyze early warning signs. Telemetred data are more useful than volcanologists visiting a volcano to carry about measurements or retrieve information stored in instruments set up on the volcano.
Monitoring volcanoes from instruments on satellite in space can be valuable, particularly in cases where is no other kind of monitoring available on the volcanoes themselves. Many of these so-called gremote sensingh technique unfortunately need specialized processing facilities, and picture (gimagesh) are expensive to obtain. However, the processing of images from space can take place anywhere, and therefore collaborative projects with institutions that have such facilities and the required financial support should be encouraged.
Some techniques that may be useful in monitoring potential volcanic cone collapses.
Visual observation is the cheapest and most practical technique.
Earthquake recording using seismographs can result in knowing where, and how often, earthquakes are taking place within the volcano and how much seismic energy they produce. They can also be used to measure other kinds of ground vibrations, such as those caused by fluids moving within volcano.
Measurement of ground movement. There are many ways to determine if, how, and how fast the sides of a volcano are moving. Among these are Electronic Distance Measurements (EDM), Global Positional Satellite (GPS) surveying, optical line leveling, and gdry-tilth networks. Other measurements can be made using displacement meters, tiltmeters, and strain meters. Tiltmeters, for example, measure the change in slope of the ground on a volcano. Measuring water levels at shore lines and water bores are useful ways of detecting ground movements.
Studying picture of volcanoes taken from satellite in space, or aircraft, or from ground.
One space-satellite method involves taking a picture of the volcano using radar signals, taking another picture some time later, and then comparing the two images to see what physical changes have taken place on the volcano. This method is known as gSynthetic Aperture Radar (SAR) interferometryh and could be useful for predicting possible volcanic cone collapses. However, the technique is highly specialized and expensive.
Making measurements of gases coming out of volcanoes. Estimates of what type of volcanic gases and how much them are produced from a volcano can be useful in forecasting volcanic eruptions in general, but not necessarily for predicting cone collapses. Satellite and aircraft can also be used to locate and record temperature changes on volcanoes using different kinds of detectors.
Taking measurements of the temperature of the ground using thermometers. Temperatures can reach several hundred degrees, especially near places where eruptions are expected. Fracturing of a volcanic cone before collapse could allow heat to the surface and temperatures may rise in many places. Satellites and aircraft can be used also to locate and record temperature changes on volcanoes using infra-red detectors.
Measuring changes in gravity over periods of time. This can help understand what may be happening beneath the surface of the volcano.
Ulawun is monitored currently using only one earthquake recorded (seismograph) and o9ne electronic tiltmeter (for measuring the tilting of the ground surface). Signals are received at Ulamona and then sent by HF radio to the Rabaul Volcanological Observatory (RVO). Instruments are used once a year at a 4 kilometer-long optical leveling line and one gdry tilth site low on the volcano. Distances between points on Ulawun were measured at one time using laser beam (EDM) and gdry-tilth sites located at mid altitude on the volcano, but these places were readily accessible only by helicopter and have since been abandoned owing to financial constraints.
The current monitoring system at Ulawun is limited: only the amount of seismic energy being released by the volcano can be estimated quickly, and the location of the earthquakes that take place within the volcano cannot be determined at all. Similarly, no good interpretation of ground movement is possible because the single electronic tiltmeter in use will provide a measure of movement only in the immediate area of the instrument.
The monitoring system at Ulawun therefore is very limited. However, both instruments – seismometer and tiltmeter – can indicate whether the volcano is becoming restless, and volcanologists can then set up additional equipment on the volcano, if it is available.
The choice of where to install new monitoring equipment on Ulawun (whether for long term monitoring or as response to suspected increasing activity) would be helped greatly by a better understanding of the physical structure and underground magma routes of the volcano. This could be done through detailed geological investigation on Ulawun, such as mapping of the different rock types and structures and modern geochemical analysis of the rocks and deposits. Geophysical investigations – such as a temporary network of several seismographs – could also help provide new information on the structure of Ulawun volcano.
Recommendations B : Monitoring of Ulawun volcano.
1. A better understanding is required of the underground magma system of Ulawun, together with a detailed map of the geological structure of the volcano and the surrounding area (see Recommendations A) so that the best network can be established.
2. Funding is required for an enhanced, permanent, monitoring network involving more instrument (for earthquake and ground-deformation measurement) together with commitment to the financing of future maintenance and operating costs.
3. Instrument for a field network should be kept in reserve at the Rabaul Volcanological Observatory for rapid deployment to Ulawun in times of crisis, together with funds available to finance installation at short notice.
4. Collaborative projects on the remote sensing of Ulawun should be established between the Rabaul Volcanological Observatory and an institution having the appropriate technical capacity to obtain and analyses satellite images of the volcano.
Tsunamis or seismic sea waves are generated by sudden disturbance of seawater, most commonly caused by large earthquakes beneath the sea floor or by landslides (on land and on the seafloor) and volcanic eruptions. A substantial amount of water must be displaced quickly for a tsunami to form.
Storm waves crashing onto the shore can be impressively large and powerful. But tsunamis can be more destructive because they have much greater energy than is provided by sudden undersea events such as earthquakes, volcanoes, or large landslides. Thousands of waves one or two meters high may pound a coast during a storm. In contrast, only a few large gwavesh strike a coast during a tsunami and these can reach great heights – up to 15 meters in the cases of recent Sissano lagoon tsunami – and cause far greater devastation that extends hundreds of meters inland.
Tsunami is a Japanese word meaning gharbour waveh. The effects of tsunamis are magnified in harbours, bays, and other inlets of costal areas, yet tsunamis can travel at great speed across wide expanses of deep ocean without even being noticed. Only when they reach shallow water and the tsunami piles up to form high waves that crash onto the coastlines, is their terrifying energy seen and felt.
Producing small tsunamis in experiments in a laboratory tank can provide valuable information about the way real tsunamis form and move through the oceans. This photograph is of a wave being formed in a laboratory tank at Monash University in Melbourne (Australia). A heavier liquid (orange) has been poured suddenly down a slope, on the right, into a lighter liquid (dark blue) forming the wave. The lines forming the grid in the background are only 10 centimeters apart.
Many islands and coastal volcanoes have the potential to produce devastating tsunamis by collapsing into the sea. The larger the amount of material that can collapse from the volcano, the larger generally is the resulting tsunami. An understanding of likely impact of tsunamis in any one area requires accurate topographic and seafloor mapping, and scientific research, particularly in the field of mathematics, computer modelling, and fluid dynamics to produce a gmodelh of where the tsunami would go and how large it could be. This then should be combined with information on the distribution of population and investment to determine what is at risk.
A destructive collapse of a volcano took place at Ritter Island off the western end of New Britain coastline and elsewhere. This event represents a valuable lesson on volcanic cone collapse and highlights the issue facing emergency management authorities in Wet New Britain Province.
Present-day Ritter Island off the western end of New Britain is the remnant of a steep volcano that collapse into sea in 1888 causing a destructive tsunami. Photograph courtesy of E.Ball
There are three key points to consider in trying to understand tsunamis:
1. Initiation of volcanic tsunami – that is, the point where materials from collapsing volcano enters the oceans to create the tsunami. A significant amount of scientific research has been completed on how volcanoes collapse into water, but more work with laboratory models combined with computer simulations is required.
2. Propagation of the tsunami – that is, the ways in which tsunamis move through the ocean. The process of tsunami movement through water is well understood (the depth of water is the key). Waves heights and shapes advancing on any coastal region can be predicted for a given disturbance if maps of water depth (bathymetry) accurate to nearest 1 kilometers are available. Finer resolution (less than 200 m) is needed to predict movement in coastal areas and off-shore reefs.
3. Tsunami grun –uph An understanding of ways tsunamis hits and run up onto land coastal regions requires the following:
l Coastal contour maps. The 40 m- contour maps available for Papua New Guinea may useful, but contour at 1 m are needed to properly investigate inundations of less than 10 meters above sea level.
l Calculation of the run-up onto a coast without vegetation. This can be done quite satisfactorily.
l An understanding of the effect of dense vegetation and other features such as hills, buildings, and wharfs, in slowing down (or otherwise affecting) tsunamis. This has not yet been computed by scientists. It could be studied by using computer models, but understanding a particular coast requires additional research.
One question that commonly arises after disaster such as the 1998 Sissano tsunami in Papua New Guinea is whether some form of early-warning system can be established for the benefit of vulnerable communities. The International Tsunami Information Center, based in Honolulu, Hawaii, can provide warnings of some tsunamis for the entire Pacific region because tsunamis may take many hours to travel from one part of the Pacific to another and their passage across the oceans can be calculated and tracked in advance. However, this task is very much more difficult within a small country such as Papua New Guinea because tsunamis (like the Sissano one) may take only minutes to travel to vulnerable shoreline from the points where they originate within that country. An-early warning system might be technically feasible and would be useful for obtaining scientific information on tsunamis, but there remain severe practical problems for disaster-mitigation purpose: (1) the high costs of establishing and maintaining an effective system; e(2) how quickly people would be able to respond to a warning of only a few minutes, and (3) where they would be able to escape to if they did respond quickly.
The key to mitigation tsunami disasters in these cases is a combination of::
1. Public awareness and education of the communities likely to be affected about the nature of tsunamis and how vulnerable they are to them, with a view to communities settling away from at-risk area.
2. Warning system that do not necessarily have to depend on technologies that are expensive and difficult to maintain and sustain-for example, warning bells on beaches that could be rung by hand by people who saw approaching tsunamis, might be useful in some rare circumstances where tsunamis can be seen (in daylight) breaking a long way off-shore.
3. Introduction of basic disaster-prevention measures, including identification of escape routes and refuge.
Low-lying coastal areas in the southwest Pacific have attracted people to them because of proximity of water and for the purposes of fishing and coastal trade. Persuading people not to live within a few hundred meters of the coastal line or lower than, say, 10 meters above sea level is not easy task by authorities. Yet there are areas most at risk to the impact of tsunamis. Most of the population of West New Britain lives close to the coast and the heights of less than 10 meters above sea level. Archaeologist have evidence that people in New Britain in ancient times used to build their village on hills away from the coasts. This may have been because higher places are healthier than coastal ones, or because people there could defend themselves better fro attacks by invading groups. But another possibility is that they were aware that tsunamis could destroy coastal settlements. Living in coastal settlement appears to have been preferred only in more modern times, mostly at the urging of missionaries and government officials.
gSlowing downh tsunamis before they hit a vulnerable coastline is possible by building breakwaters out to sea. For example, Kimbe township is located in a corner between Willaumez Peninsula and the Cape Hoskins area, where the effects of tsunami might be expected to be concentrated (although this need to be confirmed by a proper investigation). A breakwater constructed in front of Kimbe township could be reduce the impact of large tsunamis to some extent. However, such structures are expensive and are too low and the tsunamis are large.
1. Tsunami modeling of the Kimbe Bay areas should be carried out using a gscenarioh collapse from Ulawun as the initiating event so as to establish the scale of the risk..
2. Education of at-risk populations throughout the southwest Pacific region is recommended so that they can react swiftly to warnings of possible tsunamis, including those of both volcanic cone collapse and earthquake origin. This can be initiated now at little cost.
3. A public awareness video on tsunamis should be produced for viewing throughout the southwest Pacific region.
4. A list of coastal, submarine, and island volcanoes in the southwest Pacific should be compiled. This should include details on the potential for collapse and the possible volumes of collapsed materials that may be involved
5. Detail bathymetry is needed, not only near potential volcano-collapse sites, but also at potential landfall areas for tsunamis of different origins, including those caused by earthquakes. This might be completed initially for coastlines facing the deep-sea trenches of Papua New Guinea, and then could be used to prioritise the most hazardous areas and generate risk maps (see below). Results also would provide a database for the required modeling.
6. Coastal studies at potential tsunami landfall areas should be undertaken. Mapping of surface deposits and geomorphology would be useful in identifying past tsunami deposits and the resulting data could be added to models of tsunami behaviour.
7. A program of inundation modelling needs to be initiated, addressing the magnitudes and geometries of tsunamis that be produced by volcano collapses of different sizes into water with seafloors of different morphology.
Emergency or disaster management falls into two main parts :
1. prevention and preparedness activities designed to mitigate likely disaster;
2. response and recovery efforts following a disaster.
These two parts are referred to commonly as the gtwo Ps and two Rs h of emergency management.
Volcanic eruptions, earthquakes, tsunamis, and other hazards caused major disasters that must be anticipated, and prepared for, by emergency management authorities in order to save lives and property. Emergency gdisasterh plans are therefore an essential part of an emergency management system. There need to be established at the local, provincial, and national level to cover both prevention/preparedness and response/recovery. Emergency plans need to take into account all of the likely hazards, as well as the people and property at risk. Furthermore, the plans need to be consistent with the national contingency plans for other natural hazards and for technological disasters.
Preparing for cone collapses at volcanoes such as Ulawun therefore depends upon establishing a broader, national or even regional framework of emergency management within which volcanic crises can be considered. This is more beneficial than a special set of recommendations focused on cone collapse and tsunami impact alone.
DOES PAPUA NEW GUINEA NEED A DISASTER MANAGEMENT PLANS
An integrated, national, disaster (or emergency) management plan is highly desirable for Papua New Guinea in order that effective emergency management practices can be encouraged and coordinated at local, provincial, and national levels. Such plan was in fact produced in 1987, but it has been promoted and is now largely unknown. The plan now is also out of date, particularly with regard to allocations of responsibilities. A national disaster plan is essential for providing a framework for implementing recommendation concerning management of volcanic crises.
The importance of a PNG Disaster Management Plan was stressed as a result of a national emergency-management workshop held in Goroko in August 1995, partly in response to lessons learnt, and experience gained, during and after the disastrous volcanic eruption at Rabaul in September 1994. A draft project proposal was written for consideration by international development-assistance agencies as a result of the Goroko meeting, but unfortunately this did not develop into an operational project. The objectives of the proposed project were:
1. to strengthen the capacity of Papua New Guinea of effectively prepare for, and respond to, all kinds of disasters
2. to integrate disaster mitigation measures into all development programs
3. to enhance the capacity of communities to reduce the impact of disaster on their social, economic, and physical well-being.
The needs for a PNG Disaster Management Plan again become obvious following response and recovery operations after the Sissono Lagoon tsunami in July 1998. The project proposal fortunately has been reinstated and, at the time of writing (November 1998), a team of emergency managers and officials is working on updating the project proposal for further consideration by PNG government authorities.
Volcanic crises begin when a volcano shows signs of becoming grestlessh and volcanologists and local communities become concerned about the possibility of volcanic eruption. For example, earthquakes may be felt on and near the volcano, or rumblings may be heard. New areas of hot ground and emissions of water vapour may appear, areas of vegetation may die back; streams may turn muddy. Small landslips may be seen on crater wall. Parts of the volcano may be push up, or subside. These situations may be perilous to the communities concerned if the signs are ignored and not reported to authorities. About 3000 people were killed by an eruption in 1951 at Lamington volcano, Papua New Guinea. There were certainly warning signs at Lamington, but they were not reported to relevant authorities and indeed many people appeared to be unaware that the mountain was even a volcano. The gcrisish did not begin until the eruption had started. This, of course, was too late for assessing the situation and evacuating the population at risk.
Some volcano may show signs die away and so the crisis fades away too. The crises has been referred to as gfailed eruptionsh, but care must be taken in calling them such because an eruption may eventually follow them after some months or even years. Rabaul volcano (Papua New Guinea) showed signs between 1971 and 1985 of becoming active again (it had been in eruption previously in 1878 and 1973-43), and there was great concerned particularly between 1983 and 1985n when Rabaul town was partly evacuated. But the signs die away and many people thought the threat had passed. Then, nine year later, i9n 1994, eruptions began with only 27 hours of warning. Some eruptions therefore can take place with relatively little immediate warning.
Volcanic crises reach a peak during an actual eruption, which is when people are at greatest risk, but may continue well after an eruption stops as secondary lahars can take place, particularly during wet seasons. These can be times of confusion and uncertainty, especially if the affected communities and the emergency-management agencies are poorly prepared. There also times of great stress, which can be made worse if the media are demanding and sympathetic of authorities. Furthermore, foreign experts may come to the scene of the crisis and not work effectively and in close collaboration with local authorities. The best interests of the affected country should not be disadvantaged at these times. Appropriate mechanisms should be put in place to screen requests from the international community seeking permission to investigate disaster areas.
Protocol for visiting scientists and other experts should be established well before crises develop, including the establishment of rapid-development scientific teams who have prior approval to investigate affected areas. This ensures that valuable available data and information are not lost through delays caused by the slowness of official approvals during the actual time of crisis.
There are five concepts to consider in developing volcano-emergency plans:
1. Volcano Alert System
A national accepted and well understood system of volcanic-alert levels is the key tool for emergency managers to use when making a response associated with the volcano crisis. The volcanic-alert system should provide clear massages to the affected community and to emergency-management agencies concerning the level of the threat on the volcano. The particular level of volcano alert determines the response by those affected and the agencies concerned. All responses associated with the volcanic crisis should be related to a specific alert level that is set by the volcanological agency monitoring the condition of the volcano. Responses commonly are based on consultation and agreement between volcanological and emergency-management agencies.
The lowest level of alert are good opportunities for making sure that emergency-response plans are up-to-date and emergency resources are available, should volcanic activity increase. Early planning and preparation at these levels pay their greatest rewards at times of crisis later on. The change in volcanic activity may be gradual or take place very quickly, so the plans must be simple and flexible and should always be at hand and ready for use.
2. Hazards and Risk Mapping
Volcanic hazards maps are based on geological mapping of volcanic deposits from ancient eruptions and on historical records of volcanic eruptions. They define volcanic hazards zones on and around a volcano; identify areas at risk from any future volcanic events; and help to develop evacuation plans to protect the people identified as being at risk from the volcanic activity. Risk maps may also be used in development and land-use planning by local and provincial authorities. These show where people, investment, and agricultural lands are most at risk and what would be lost if a volcanic eruption to take place.
3. Volcano Monitoring and Warning
Adequate volcano monitoring systems must be established at dangerous volcanoes, as they always give some indication of an impending eruptions. These indications commonly may be taken as warning signs that lead to evacuation of the people at risk and therefore to mitigation of volcanic disaster impact (se g Monitoring and forecasting volcanic eventsh above). Warning systems should be an integral part of monitoring systems. They agency monitoring the volcano should issue regular bulletins containing information about the current status of the eruption and predictions about increasing or decreasing volcanic trends. These should be made available to the public and media. Having only one agency or person acting as the official interface with the public and media is important, as more than one can lead to the contradictions and confusion.
4. Education and Awareness
People will be more inclined to respond to warnings to an eruption if they understand the risks associated with a volcano. Education must include (1) local communities who may be affected by an eruption and (2) community leaders and managers who will be required to respond to the eruption on behalf of the communities. An informed population is an important part of any emergency management plan, and major efforts must be made to provide the population with factual information about volcano, the hazards facing them, and the efforts being made to mitigate them. Locally produced videos, for example, can be very useful for this purpose. Educating the media about volcano, its monitoring and the disaster plan, is also a very important part of the education process.
5. Response planning
Emergency (or Disaster) Plans must identify who is involved in the response and recovery stages of a volcanic eruption, what their respective roles and relationships are, and the resource that will be required to carry out the plans. They also need to consider the training of those people who will be involved, and they must be exercised to see that they work properly. Integration of the individual responses and plans of all affected agencies, should be based on a common strategy that will allow them to work together in the event of a volcanic eruption or cone collapse. Everyone involved in volcanic crisis must understand the basis on which the controlling authority will work. The plans of individual agencies should complement each other, rather than conflict or duplicate.
Small to moderate volcanic eruptions tend to create a local crisis, and therefore should be controlled by the local emergency management authority. However, such authorities will need to seek advice and resource from larger provincial and national organizations if the problems become larger than they can handle. Provincial and national emergency organizations obviously have a strong role to play in supporting the local organization to deal with the local crisis. Primary control of a crisis or disaster may have move up through the emergency management system as the size of the crisis grows and the local resources become over-whelmed.
Any plan for dealing with the hazardous volcanic eruption must recognize that the first task is the evacuation of areas at risk. These areas need to be identified on hazards maps that are made widely available to the general public. A disaster response plan should (1) promote the concept that affected communities must be somewhat self-reliant and (2) encourage self-evacuation to safe areas as the level of volcanic activities increases. Evacuees in temporary care centres should be expected to receive some assistance, as the length of time they may have to spend away from an evacuate area will range from weeks to years.
There is usually a large demand for information about the volcano during a volcano crisis. Information management is a key aspect of any volcanic crisis. Each organization involved in preparing a volcano alert plan should identify the sort of information it will require. For example, health authorities may want to know about gases or contaminated water, aviation authorities about distribution of eruption clouds. Disaster plans should identify sources for this information. Information protocols should be established long before the eruption. For, example, a volcanological observatory may be responsible for production of regular volcano information bulletins on the status of the eruption for use by emergency managers, the media, affected industries and the public, but would not be responsible for, say, detailed health advice on water quality.
Rabaul Volcanilogists Obsevatory (RVO) is responsible for volcano monitoring and hazards mapping throughout Papua New Guinea, including Ulawun volcano. RVO recently has been working on the completion of an Ulawun Volcano Disaster ( or Operation) Plan for consideration by West New Britain Province authorities. The draft Plan includes information on:
l The respective role of RVO, the West New Britain Provincial Disaster Committee (PDC) based in Kimbe, and the National Disaster and Emergency Services (NDES) based in Port Moresby
l The logic of the Operation Plan
l Identification of hazards zones and high-risk areas on Ulawun
l Identification of the responsibilities of the different authorities and chains of communication and operations
l Details of the system of volcano alert levels for Ulawun
l A table showing the likelihood of different types of eruption at Ulawun, based on its history
l Appendices listing important types of information such as population figures, contact details for key organizations and personnel, pick-up points, and evacuation centres.
The volcano alert system proposed for Ulawun is based on a system incorporated in the previous Provincial Disaster Plan that was revised following the September 1994 volcanic eruptions at Rabaul in East New Britain Province. Many lessons were learnt by emergency management authorities during and after the Rabaul eruption and the former four-stage alert system for Rabaul was abandoned.
The principle features of the proposed Ulawun volcano alert-level system set out on the page opposite are :
l Only three stages of alert
l Stages are colour coded (green, orange, and red)
l The stages focus on the level of the threat to life and property, but do not specify how long the volcano will take to reach a higher level of alert
l A grecoveryh stage is added in order to assist a displaced to population to return to their home area and to resume normal living conditions.
A similar three-stage system is likely to be recommended by RVO to NDES for other volcanoes throughout Papua New Guinea.
State of Ulawun volcano
Threat to life
Low level activity: white vapour emission; occasional ash emission, occasional night glow; possible light ashfall; affects summit area only. g Normalh condition for Ulawun.
Routine PDC meetings. Officers appointed. Review Operation Plan. Long-term preparations and maintenance (roads, telephones, population census, etc.). Education campaigns in danger areas.
Moderate activity: vapour and ash emission; explosions; night glow; fire fountains; small pyroclastics flows or lava flows; ashfall downwind; affects area down to mid-slope (e.g. ashfall on gardens, plantations, logging areas)
Medium or localized
Coordinator for National Disaster Committee and PDC alerted. PDC meeting for review of Operation Plan. Preliminary, low cost measures : ensure equipment is in order (telephones, radios, roads, trucks, etc.) Ensure readiness of temporary evacuation centers. Public information in danger area (simple safety measures and the Operation Plan). Tok-save messages. Controlled information to media.
Very strong activity or flank eruption: tall, dark, eruption column; loud explosions; heavy ashfall (downwind); pyroclastic flows and/or lava flows down the flanks; possible flank eruption; affects lower flanks (where inhabited and including infrastructure); or severe distant ashfall. A major cone collapse of Ulawun would be included in this category
High or widespread
Activity threatens lower parts of the volcano. Public announcements (Tok save messages) instructing orderly evacuation according to the Plan. Risk of panic among population. Destruction of gardens and plantations. Possible loss of property. Organized evacuation.
Return to low-level activity
Investigating the damage. Danger areas reopened to public (some areas may remain restricted). Reconstruction may be needed. Resettlement of part of the displaced population may be needed. Review Operation Plan. Review regulations on land occupations. Payment of overtime and requisitions fees.
Development of the comprehensive and up-to-date West New Britain Disaster Plan requires incorporation of the approved Disaster Plan for Ulawun. Development planning will also need to consider for the effects of eruptions from other active volcanoes in the province such as Bamus, Lolubau, Pago/Witori, and Maklia/Dakatau, as well as the impact of tsunamis originating from volcanic cone collapses, earthquakes, and submarine volcanic activity and landslides. Other natural hazards such as landslides, flooding, and drought need consideration too.
A key activity prior to development of any Provincial Disaster Plan is an understanding of what is at risk in West New Britain Province. Economic development in the West New Britain has been significant over the past 20-30 years as a result of the creation of oil palm, timber, and eco-tourism industries. Services have grown in the support of them and population has grown, mainly from influxes of settlers from other parts of Papua New Guinea. Oil palm developments have extended up from the coast and only a few meters above sea-level where they are vulnerable to tsunamis. The risk in West New Britain to effects on natural hazards such as volcanic eruptions and tsunamis therefore is much greater than it was, say, 25 years ago.
Mapping of hazards, investment, vulnerability, and risk can be undertaken quite routinely using established methods and by providing results on user-friendly computer-based geographic information system (GIS). Such systems provide a powerful yet inexpensive way of accessing information that is essential for
emergency-management purposes, including planning and assessment of risk. GIS can be used to provide rapid answers to questions about the distribution of vulnerable communities and how best they may be evacuated and cared for at times of crisis; and about the best, low-risk places for promotion of economic development and for approved land-use management strategies.
Recommendations D : Volcanic Emergency Management
1. A risk mapping project should be undertaken as a matter of urgency West New Britain province in order to map hazard zones (e.g. for volcanic eruptions, earthquakes, and tsunamis), to identify communities, investment, and infrastructure that are vulnerable, and to make specific recommendations for risk mitigation. Results should be fed into provincial government plans emergency management response, economic development planning, and land-use strategies.
2. Volcanically vulnerable areas require the development of specific emergency-management plans. These plans must (1) identify the responsibilities and role of all emergency-management agencies involved in a crisis, (2) allow training, and (3) be exercised regularly in order to test their effectiveness.
3. All initiatives aimed at improving the efficiency of communication system among emergency-management agencies are strongly supported. Effective linkages must be established between all relevant agencies involved in the responses to a volcanic crisis.
4. Education and awareness plans for active volcanoes and volcanic eruptions need to be established and promoted throughout the southwest Pacific region. The IAVCEI videos (gUnderstanding volcanic hazardsh and gReducing volcanic risk) should be reproduced in the Tok Pisin language for use in Papua New Guinea, Solomon Islands, and Vanuatu.
5. Volcano alert systems should be developed for areas of volcanic risk throughout the southwest Pacific region in order to act as baseline for emergency management decisions. Volcano alert levels should be determined by volcanologists observatories having the appropriate monitoring and administration systems to undertake this task and in conjunction with local authorities.
6. The concepts of the Papua New Guinea Disaster Management Project is strongly endorsed.
7. The work of the Rabaul Volcanological Observatory as Papua New Guineafs primary source of volcano information and advice is strongly endorsed. National volcanological observatories have an important public-safety role to play. Observatories should be established in those volcanically active southwest Pacific countries that do not already have them.
8. Attention should be given to the establishment of rapid-deployment scientific teams who have prior approval to investigate affected areas. Appropriate mechanisms should be put in place also to screen requests from the international community seeking permission to investigate disaster areas.
The 25 recommendations produced as a result of the Ulawun Workshop cover a broad spectrum Decade Volcano Workshop cover a broad spectrum of topics – from improved scientific understanding of the structure of volcanoes capable of collapsing and producing major debris avalanches; to monitoring and forecasting of cone collapses and the effects of resulting tsunamis; to important emergency-management that can be accepted as practical mitigation measures.
The recommendations represent a comprehensive approach to lessen to threat of volcanic eruptions, including volcanic cone collapse and tsunamis, throughout the southwest Pacific region. Some of the recommended actions can be undertaken fairly quickly and relatively cheaply. Others will require greater, long-term commitment.
Volcanic hazards will continue to threaten populations and development in the southwest Pacific region and so effective mitigation of volcanic disasters must continue to be an aim beyond the years of International Decade for Natural Disaster Reduction.