A Discussion Of The Eruption Mt Helena


A Discussion Of The Eruption Mt. Helena In 1980 Essay, Research Paper

Over the past fifteen years substantial developments have been made within high magnitude-low frequency volcanology. It is now becoming increasingly possible to predict an eruption; to understand the processes of eruptions and to develop relevant responses and adjustment programmes (Chester 1993, McCall 1992, White 1972). Yet, regardless of this there are problems. Although science has developed new prediction methods, the accuracy of these is hard to judge, as despite frequent high magnitude-low frequency eruptions during the holocene, they are now relatively rare, thus making adjustment programmes problematic. Volcanologists have however, decided upon two types of programmes (McCall 1992). Firstly, predicting the volcano’s future eruptions, carried out through studying past behaviour and secondly, setting up permanent monitoring systems allowing for rapid detection of new seismic activity. General global programmes cannot be augmented however, but, in the aftermath of an eruption the responses and adjustment made can be assessed and can be used as guidelines for future high magnitude-low frequency volcanic areas. The Mount Saint Helens’ eruption was one of high magnitude-low frequency and consequently other countries have turned to the responses and adjustments made by Washington State to develop their own programmes. This essay will study the responses and adjustments made by Washington State and their effect on programmes developed by Japan, New Zealand, the Philippines and the Indonesian government in relation to Una Una. Studies into Mount Saint Helens, situated in the volcanic region of the Cascade Mountains in Washington State, USA, began mainly in the late 1930’s by Verhoogan (Geological Survey Prof. Paper 1982). His initial report based on a study of rocks and vegetation, concluded that there had been volcanic activity until recently due to studies revealing the lava to be only a few 100 years old; but it was not until the 1970’s interest into Mount Saint Helens increased due to the realisation of its potential hazardousness, prompting The Congress Under the Disaster Relief Aid (1974) to deliver a brief to the United States Geological Survey (USGS) stating their beliefs of a potential eruption and suggesting possible responses and adjustments that could be implemented in the event of the disaster (Chester 1993). In summary, they believed the prime aim was to reduce loss of life, property and natural resources that often takes place as a result of volcano’s eruptions and its related consequences, such as land-slides and mud flows. As a result of the initial brief, steps were taken based on the suggestions made, to ensure the selected aims would be met. Firstly, the USGS published a hazard map of the area and secondly, they informed the relevant agencies of the warning signs of an eruption and the subsequent guidelines that need to be taken, for example, restricting access to certain areas. As will be seen later these initial steps proved successful. In 1975 Dwight Crandell and Donal Mullineaux wrote an article warning of an imminent eruption of Mount Saint Helens within the next 100 years and perhaps even before the end of this century (Geological Survey Prof. Paper 1982). They wrote of the eruptive history of the volcano and produced zoning maps, predicting those areas which would be most effected. Later, Crandell and Mullineaux wrote a further, in depth report (1978) commissioned by the USGS, titled, “Potential Hazards from Future Eruptions of Mount Saint Helens Volcano, Washington” (Chester 1993). Its publication came about as a result of a new research programme investigating the potential hazards in the Cascade Region. From their previous assessments of the area and their subsequent reports they demonstrated that future eruptions will be of high magnitude, producing lava flows, pyroclastic flows, domes, tephra and mud flows – thus becoming hazardous for a multitude of people within the area. This report was widely distributed to the Washington State Governors representatives, Federal and State officials and local agencies in south-west Washington. The Governors representatives misinterpreted the document and thought an eruption was imminent. As a reaction to the report, although at the time being thought of as an overreaction, monitoring and assessment of the volcano commenced (Saarinen and Sell 1985). From the beginning the monitoring process proved problematic as knowledge of past eruptions was relatively sparse, both for Mount Saint Helens or similar Cascade region eruptions as well as for other high magnitude-low frequency eruptions worldwide. Monitoring of the volcano included installing seismometers to detect earthquakes signifying an imminent eruption through monitoring precise ground surface movements and detecting swelling in the volcano. Despite this report being credited for the monitoring and assessment systems set up in the volcano’s vicinity, the report (referred to as the “Blue Book”) nonetheless caused problems amongst many groups including the general public, mainly due to it contradicting the current and accepted perceptions of risk – thus the report can be partly to blame for the misunderstandings that arose (Chester 1993). Two factors contributed to the confusions. Firstly, the last Mount Saint Helens eruption was in 1857 and the last volcanic activity in the Cascade region was between 1914 and 1921, thus the people were reluctant to believe another eruption was imminent. Secondly, those involved in the survey had little experience in predicting the course of volcanoes, thus often information released was inaccurate. Although clearly the report bought about confusions, nevertheless, in retrospect, it is possible to see how accurate their predictions were – one of their main pitfalls was that the failed to predict the intensity of the blast. By the beginning of March 1980, when the first signs of earthquakes became apparent, the only instrument monitoring the volcano was a seismometer situated on the western flank. From this instrument the early warning signs were registered and activity gradually increased; further instruments were installed and aerial observations were carried out (Geological Survey Prof. Paper 1982). Again after the small eruption on March 27th, 1980, the programmes and systems were intensified. At all times, officials within the State and the surrounding area were kept well-informed as were agencies and the general public. The United States Forest Service (USFS) lead the news conferences which were broadcast three times a day on both the radio and the television. From studying the monitoring and warning process’ carried out before the eruption and from seeing the responses and adjustments made after the eruption, the effectiveness of these initial actions can be measured and from it changes can be implemented for the future. In retrospect, the responses and adjustments taken proved to be both successful and unsuccessful (Chester 1993). Successful aspects include the speed at which the USGS set up monitoring stations and produced and distributed hazard maps after the initial earthquakes in March. Through this rapid process it enabled scientists and volcanologists to verify their opinion of an imminent eruption to officials and the general public. Interaction between the USFS and the USGS was good, mainly because the volcano lay within their land. They created zones within the area and by March 27th, they had set up ‘no public access zones’ and ‘restricted access zones’. Roads were shut and the inhabitants were fully informed ensuring the evacuation plans were widely known. Another positive aspect of the responses and adjustments were those taken by the Federal Emergency Management Agency (FEMA); they became involved after the main eruption of May 18th, once President Carter had declared it a disaster area. They successfully coordinated the search and rescue programme and the administration of disaster relief; in addition, they developed technological information networks ensuring relevant information could be widely spread. Despite the positive aspects of the responses and adjustments, there are however, negative ones. Research carried out after the eruption to assess success or failures shows that the warnings were not fully effective due to their inconsistency; often they were unclear or did not fully emphasize the potential dangers, for example, despite Crandell and Mullineaux’s warning of pyroclastic flows to the east of the volcano in their “Blue Book”, they were not given the significance they should have had, thus those areas did not develop contingency plans. It is now thought that if the USGS had played an increased role and developed better communications this problem could have been alleviated. A further negative aspect is that despite the USFS proving to be efficient, its contingency plans were based on the results of their experience of forest fires. Although this was an adequate starting block, the plans should have been advanced as the scale of the volcanic hazard was far greater than any previous hazard posed by a forest fire. Additionally the State of Washington must apportion some of the blame. For despite being a hazardous area due to the volcanoes, their emergency services were badly coordinated and underfunded. Finally FEMA only became involved once President Carter, declared the state a disaster area – loss, mainly of material goods could have been reduced had they become involved earlier. With almost complete certainty, Mount Saint Helens will erupt again, although it is almost impossible to predict when (Geological Survey Prof. Paper 1982). Seismologists at the University of Washington and the USGS are relatively optimistic that the pattern of pre-eruptive activity will be crucial in providing a warning of an eruption. Through more recent studies into the success of the responses and adjustments made in 1980, additional ones can be developed and unsuccessful ones altered. After the next eruption therefore, the subsequent loss of life, property and natural resources will be kept to a minimum. In addition to the advanced response programmes that will be implemented when a future eruption commences, other steps have been taken to heighten people’s awareness of the potential hazardousness of Mount Saint Helens, for example, information centres have been set up within the area enabling people to understand the effect a volcanic eruption can have. Crandell and Mullineaux’s work and reports into Mount Saint Helens accurately predicted the eruption and the emphasis they placed on the dangers of such high magnitude-low frequency eruptions was successful. Had they not placed such emphasis on the potential dangers, it is certain that the loss would have been far greater. With regret, the only downfall of their work was their inaccuracy in predicting the intensity of the blast. The Mount Saint Helens eruption was one of high magnitude-low frequency and in a developed country. Prior to it there had been few similar eruptions, thus people were unaware of its hazardousness. As a result of the eruption, both developed, for example, Japan and developing countries, for example, the Philippines have realised the future dangers they could face from their volcanoes; thus the Mount Saint Helens disaster has prompted others to develop monitoring, surveillance and contingency plans, so that in the event of a disaster, they will be as prepared as possible. Many countries have based their plans on the successful aspects carried out by Washington State and used their unsuccessful ones to ensure the same pitfalls are not repeated. A little over 3 years ago, Japan experienced a high magnitude-low frequency volcanic eruption. Through their increased awareness due to the Mount Saint Helens eruption, Japan found itself competently prepared and through successful coordination, losses were kept to a minimum. In June 1991, Mount Unzen in Japan erupted after a lengthy initial build-up. Yet despite many eruptions, pyroclastic and mud flows, relatively few people were killed (Chester 1992). The few deaths resulting from the eruption were impressive, given the fact that Japan has a very high population density. This success rate can be attributed to the excellent pre-planning and the effective coordination and implementation of the plans once the eruption began. Through the government’s recognition of the high density of population especially around the volcano, they and the general public became aware of the need for pre-planning. Through learning from past mistakes made due to Washington State’s under-funded and ill-equipped emergency services, they realised the importance of providing substantial resources, both technological and financial, for all aspects; including emergency services, surveillance experts and personnel. The Japanese have developed a very high-tech surveillance system, which is used to constantly monitor the most potentially dangerous volcanoes (Chester 1992). As with Mount Saint Helens, the Japanese government has drawn up hazard maps of the area, enabling agencies, government officials and the local population to understand those areas which are most dangerous. In addition, the government has also set up the “Japanese National Programme of Predicting Volcanic Eruptions” – this was initiated by the eruption of Sukura-Zima in 1974 and Mount Saint Helens. Through developing those prediction methods used at Mount Saint Helens, the Japanese were successful in determining the eruption. In addition to this, the National Programme stressed the importance of a extensive warning network and trained emergency services. As has been previously mentioned, part of the faults of the Mount Saint Helens disaster lay within the poorly funded emergency and rescue services. The Japanese government found themselves in a position to learn from the mistakes of the USA government. Similarly to the Mount Saint Helens disaster, Japan’s plans include evacuation, this aspect must be carefully worked out and revised due to the ever-changing population and economy. The eruption at Mount Unzen was a severe test for the preparedness of the country as a whole and for those within the vicinity. As soon as initial activity began, in likeness to the Mount Saint Helens disaster, surveillance and monitoring was stepped up and prediction methods used. Once volcanic material began to be ejected, the plans began to be bought into action; people were evacuated and were only allowed back once the area was considered safe. The planned evacuation proved successful due to its thorough development prior to the eruptions; this is in comparison to Mount Saint Helens, where at times inconsistency within plans led to confusion, thus Japan had learnt from Washington State’s mistakes. (See table 1 for responses and adjustments made in relation to volcanic activity) Through this example, it can be seen that Japan coped well with the high magnitude-low frequency disaster; the reasons behind this can be attributed to the excellent coordination and mobilisation of resources. Japan will continue to be successful with such disasters due to its realisation of the importance of pre-planning, technical and financial support. Part of the success can be attributed to Japan’s increasing awareness of its potential hazards, which came about as a result of Mount Saint Helens. It was through studying Washington State’s positive and negative aspects that Japan managed to successfully develop their own strategies – thus despite the magnitude of the eruption they were able to keep their losses to a minimum. Such high magnitude-low frequency events also occur in New Zealand, although not with the same intensity as in Japan. Prior to the 1980 Mount Saint Helens eruption, volcanoes were not seen as being potentially hazardous. As a result of this disaster, New Zealand to, became interested in their volcanoes, with the realisation of the consequences of such an eruption (Dibble 1985). With increased technology and by learning from both the positive and negative responses made both before and after the Mount Saint Helens eruption, New Zealand found themselves to be in a better position for predicting and responding to volcanoes. In response, New Zealand set up a special Planning Committee on Volcanic Hazards, this committee has developed a number of actions to be taken to help minimise risk and devastation. These include (Dibble 1985) :- * The likely areas and types of future activity. * The risk to public safety. * The setting up of monitoring systems to predict the eruption. * Government resources that can be bought into use in the event. * Practical steps that can be undertaken by regional and local authorities where a threat is identified. New Zealand fully understood the need for pre-planning and recognised the extent to which the effects of the disaster could be reduced through specific programmes. In the light of this, initial investigations were augmented to assess the volcanic areas. Through scientific studies uncovering past eruptions, they calculated the probability of future ones; following on, they researched into the possible damages that could result from such an eruption; for example, the cost to the economy, people and livestock. From the results obtained and with the government’s dedication, successful programmes were coordinated. A good example of this is in Auckland. This volcanic district encompasses over 50 eruptive centres including the Auckland metropolitan area. To date the type of volcanic activity expected in this vicinity includes lava fountains of over 200 metres in height and subsequent lava flows, tuff deposits 10’s of metres thick and ejections of rock debris. From this the government have been able to comprehend the volcano’s severity and they expect few survivors close to the source. They also concluded that tidal waves could be possible. Additionally, through calculations they have been able to estimate the probability of eruptions, yet despite a low risk, the risk to resources, economy and people are high (Dibble 1985). AUCKLAND VOLCANIC FIELDS (for example, Panmure Basin) AREA DESTROYED 3-28 km PROBABILITY IN 100 YRS. 2.5 – 5 % POPULATION AT RISK 6000 – 100,000 PROPERTY AT RISK (M$) 64 – 3600 Clearly therefore, both Japan and New Zealand have benefitted from being able to gain insight into successful surveillance methods, responses and adjustments that should be implemented; but it is not purely these developed countries that have benefitted, but also less developed countries have been able to look to Mount Saint Helens to guide their decision and implementation process. On June 15th and 16th, after two months of initial activity, Mount Pinatubo in the Philippines erupted, an eruption lasting for 15 hours, spreading ash into the stratosphere and culminating in large pyroclastic flows. The area surrounding Pinatubo has a very high population as only 100 km southeast of the volcano is the capital, Manilla and only 15 km to the east, is one of the United States largest overseas military installations, with over 15,000 personnel. The responses and adjustments the authorities made were terrific, especially given the fact they are a less developed country – through looking in retrospect at the Mount Saint Helens eruptions, the Philippine government learnt from the American government and through this learning process they developed the ‘Philippine Institute of Volcanology and Seismology’ (PHILVOLCS) (Chester 1992). It was this institute that began the well-devised monitoring process two months prior to the main explosion. It was through studying plans made by Washington State, that the Philippine government and PHILVOLCS were able to understand the necessity of substantial pre-planning. Prior to the eruption they devised evacuation roots and prediction methods to be used; they also developed a series of ‘alert levels’ which were communicated to the public, warning of the predicted time for eruption (Guest 1991). (See table 2 showing the responses and adjustments made in relation to the volcanic activity.) Clearly then the programmes devised by the Philippines were successful and the country substantially gained from the Mount Saint Helens experience. This can evidently be seen by the fact that the responses and adjustments they made were not in keeping with other less developed countries and many successful aspects were similar to those made before, during and after the Mount Saint Helens eruption Another example of a less developed country setting up successful surveillance systems and contingency plans is on the Indonesian island of Una Una, where in 1983 the Cola Volcano erupted. Yet despite the nature of the country and economy as a whole, the country lived up to its reputation of being able to manage such a disaster excellently (Chester 1992). As a result of the Mount Saint Helens eruption, the government officials on the Indonesian island were able to assess the importance of certain factors and processes, thus they gave priority to scientific investigations, integrating these findings with civil defence measures and developing skilled responses and adjustments programmes. As seismic monitoring detected activity, as with Mount Saint Helens, the surveillance was rapidly stepped up and as minor explosions began, the evacuation procedure was implemented. As volcanic activity increased so did the speed at which they were evacuated and within 24 hours, the island’s residences had moved – an incredible feet made possible by the use of a large number of boats. The death toll, through excellent evacuation procedures, was zero, but due to the size of the eruption on a small island, virtually all housing, livestock and plantations were destroyed. Clearly the evacuation was a tremendous success, but recovery from the eruption will be a long, slow process, due to the poverty, lack of capital and insurance. The Mount Saint Helens eruption has been hailed as the most significant eruption this century. In its immediate aftermath and in years to come it can be used, firstly, as a symbol of the capabilities of a high magnitude-low frequency event and secondly, to help generate other response and adjustment programmes. Vast quantities of information was produced after the eruption which has proved and will continue to prove extremely useful. Clearly this eruption woke people in other high magnitude-low frequency volcanic areas into realising their potential. As has been seen, relatively soon after the event many other countries began monitoring and assessing their volcanoes and devising response programmes. In time, they too experienced similar eruptions, where-by, as a result of Mount Saint Helens, they found themselves well-prepared – even some of the less developed countries. Through their assessments and preparations they were able to keep losses to a minimum. Additionally, it is fully understood globally, that assessment techniques and response programmes must be continually revised and up-dated where necessary, especially in the light of improved science and technology. Furthermore, a number of measures should be taken to ensure success in all aspects, for example; * The importance of planning. * The role of the emergency services. * Hazard information and the public. The importance of planning Planning at all phases is essential for an effective response to a natural hazard as people cannot successfully respond to an unknown phenomena. Those responsible, for example, agencies and officials, must plan in advance aspects such as evacuation and search and rescue procedures. Once this has been carried out they must ensure the information is accurately relayed to the public. Following on from the responses and adjustments made after the Mount Saint Helens eruption, there is substantial evidence showing that the most successful aspects were those where plans had been taken from similar past experiences, for example, despite not fully knowing how to deal with the problem of fallen ash, the emergency services treated it in a similar way to a snow storm; this proved to be very successful. Through innovation potential problems can be overcome. The role of the emergency services A successful emergency service is paramount. Not only must the rescue operation be expertly coordinated, with good communication to all involved, but the services and agencies must intervene early on. This was one of the prime mistakes made by Washington State in the wake of the eruption. FEMA became involved relatively late, thus perhaps decreasing the success of their efforts. But through the recognition of this other countries have been able to learn from the mistakes. Furthermore, the emergency services must have adequate resources available to them, both technical and financial, ensuring nothing can hinder their role. Hazard information and the public When faced with a disaster such as a volcanic eruption, a good ‘public information organisation’ is essential. The organisation must gather news from emergency operations, provide press conferences and ensure professional people within the field are consulted. Subsequently, the information must be relayed widely, accurately, quickly and simplistically to the public, ensuring all who could be effected are informed. FEMA took control of this aspect and to date it is probably the finest example of how it should be done. They ensured information was conveyed quickly and accurately at the same time as consulting experts within the field. Clearly then, it is possible to reduce the effects of such an eruption through careful monitoring and planning. But due to a major restricting factor often being financial resources, this could prove to be problematic for less developed countries. In this case they must be innovative and resourceful and develop programmes to the best they can, as was seen by the Indonesian government on the island of Una Una and the Philippine government in relation to Mount Pinatubo. There are certain aspects which are going to be poorly devised, but through assessment after the eruption, other countries can continually revise their own programmes, thus there must be a world wide flow of information ensuring all areas with similar volcanoes can benefit. This flow of information can come through The International Decade for Disaster Reduction, which developed due to increasing reports by mainly the media on large natural disasters. The aims for the decade were stated by the United Nations General Assembly as reducing loss of life and property and minimising social and economic disruption, especially in less developed countries. It set out four main goals. (Burton et al 1993) Firstly, improving the ability of a country to mitigate a disaster and where necessary, supply warning systems. Secondly, to devise appropriate strategies, taking cultural and economic diversity into account. Thirdly, to use comtemporary scientific and engineering skills to reduce loss of life and property. Fourthly, to develop ways of assessing, predicting and mitigating natural disasters through training and educating those involved, demonstration programmes and transferring relevant technology. Through international support, less developed countries should therefore see a reduction in damages to their country and a reduction in the number of deaths. But for success, all who could be effected by a disaster will have to be shown how they can help themselves – the aims set out by the United Nations are high and towards the latter half of this century, their success can be measured. BIBLIOGRAPHY Burton et al (1993) The Environment as Hazard; Guilford, Guilford Press Chester, D (1993) Volcanoes and Society; Edward Arnold Dibble et al (1985) Volcanic Hazards of North Island, New Zealand-Overview; Journal of Geodynamics 3, p. 369-396 Geological Survey Professional Paper 1249 (1982) Volcanic Eruptions of 1980 at Mount Saint Helens-The First 100 Days; US Government Printing Office Guest, J (1991) Unzen Volcano 1 Guest, J (1991) Mt. Pinatubo McCall, G et al (1992) Geohazards; London, Chapman and Hall Raphael, B (1986) When Disaster Srikes; Hutchinson Education Saarinen and Sell (1985) Warning and Responses to the Mount Saint Helens Eruption; New York, State University Press Shimozuru (1983) Volcanic Surveillance and Predictions of Eruptions in Japan; in Tazieff and Sabroux, Forecasting Volcanic Events, Developments in Volcanology 1; Amsterdam, Elsevier p.173-193 White (1973) Natural Hazard Research; in Chorley, Directions in Geography; London, Methuen p.193-212 TABLE 1 – The responses and adjustments made in the Mount Unzen vicinity in relation to volcanic activity. 1989 November – First volcanic tremor felt 1991 January 15 – Earthquake swarm Early April – Ash emissions May 12 – Volcanic glass recognised May 15 & 19 – Debris flows along Mizanushi River destroying two bridges. Evacuation of 1300 from Shimabara May 21 – 1100 evacuated at 0300. Allowed to return at 0555. May 23 – Domes grows and explosion produce grey clouds, 100m high. May 24 – Large explosion at 0810 produces pyroclastic flows 1300 evacuated due to risk of mud flows Material dredged from dams at night to reduce mud flow danger. May 25 – 0600 evacuation recommendation was withdrawn Dust and ash seen at 1145 Lava dome grows May 26 – Pyroclastic flows continue to within 600 metres of Kata-Kamikoba Evacuation of 3500 May 27 – Evacuation zone expanded Pyroclastic flows continue June 3 – Pyroclastic flows kill 41 and enters Kata-Kamikoba Helicopter grounded due to ash in engine June 7 – Evacuated zone increased – total evacuees= 7200 June 8 – Large pyroclastic flows Evacuation zone increased – total evacuees= 8500 73 houses destroyed June 9 & 10 – Evacuation zone increased – total evacuees= 9800 Mud flow hazard high June 11 – Large explosive event Houses, cars, windows and two helicopters damaged June 24 – Pyroclastic flows continue June 17 – Evacuation zone increased – total evacuees= 10,000+ TABLE 2 – The responses and adjustments made in the Mount Pinatubo vicinity in relation to volcanic activity 1991 April 2 – Explosion at eastern part of Pinatubo 2000 evacuated within 10 km radius June 3 – Tremor lasting 30 minutes June 4 – Tremor at 1200 June 5 – PHILVOLCS issued Alert Level 3 warning June 6 & 7 – 1000-2000 per day June 7 – Explosion from main vent at 1640 PHILVOLCS issued Alert Level 4 warning at 1700 12,000 people evacuated from Tarlac June 10 – US Air Force order evacuation of Clark Air Base at 0500 – 14,500 evacuees June 12-15 – Strong explosions, tephra columns reach 20 km Pyroclastic flows 600 more evacuees from air base Residents within 20 km are evacuated June 14 – Small mud flows 79,000 evacuated in total- 4 killed, 4 missing, 24 injured June 15 – Further explosions and pyroclastic flows Evacuated radius expanded by PHILVOLCS to 30-40 km 1342 – most violent phase June 16 – People return home June 19 – Death toll = 300

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