Mitigating Volcanic Hazard Effects:
Douglas Paton1, Kevin R. Ronan1, David M. Johnston2 & Bruce F. Houghton3
1. School of Psychology, Massey University, Palmerston North, New Zealand.
2. Institute of Geological and Nuclear Sciences, Wairakei Research Centre, New Zealand.
3. Department of Geology, University of Hawaii, Hawaii.
This paper summarizes research involving multidisciplinary collaboration between volcanologists and psychologists to investigate social vulnerability following the 1995-1996 eruptions at Ruapehu Volcano, New Zealand. This work focused on examining how physical processes interact with personal knowledge and beliefs and community characteristics to influence the social impact of volcanic hazards. On the basis of these analyses we discuss how the data can be used to assist the development of individual, community and organizational mitigation. The emphasis here is the facilitation of volcanological knowledge and expertise in threat communication, mitigation, community development, emergency planning, and response management.
Keywords: multidisciplinary research, mitigation, response, preparedness, multiple gating
While volcanic hazards such as ashfall and lava flows are essentially immutable, some of their consequences for communities, businesses and individuals are more amenable to moderation through disaster reduction or mitigation, particularly when dealing with non-catastrophic eruptions. These strategies can involve, for example, designing roofs to better withstand ashfall, encouraging adoption of protective measures (e.g., masks) to minimise ash effects on health, covering drinking water sources, safeguarding essential utilities (e.g., electricity transmission) from ash effects, and developing business continuity plans. Facilitating the effective adoption of these strategies requires that several groups, including volcanologists, social scientists, emergency managers, and community representatives, collaborate to identify needs and, by developing solutions to meet them, mitigate social vulnerability.
This paper summarizes some initial research involving collaboration between volcanologists and psychologists to investigate social vulnerability following the 1995-1996 eruptions at Ruapehu Volcano, New Zealand. The need for this collaboration was highlighted by a comparison of hazard effects following the 1995-1996 eruptions with those of a similar eruption in 1945 (Johnson, Houghton, Neall, Ronan, & Paton, in press). While similarities between these events were evident (Table 1), the 1945 eruption persisted for a longer period of time and several communities received more ashfall in 1945. Notwithstanding, social vulnerability increased during the intervening fifty years (Johnston et al., 1999; Johnston & Ronan, 1999; Millar, Paton & Johnston, 1999). Given that this change in vulnerability to volcanic hazard effects was attributable to their interacting with more complex social and economic environments (e.g., disruption to more developed utilities, transportation and economic infrastructure), understanding and managing volcanic hazard consequences will increasingly require analyses and strategies that integrate geological, social and psychological perspectives.
Table 1: A comparison of the 1945 and 1995/96 Ruapehu eruptions
Total duration 40 weeks 20 weeks
Principal style dome building sustained
Principal hazard ash fall ash fall
Secondary hazards ballistic blocks, ballistic blocks,
Adapted from Johnston et al., 1999
This paper reviews the implications of work undertaken within this collaborative framework for understanding and managing social vulnerability and promoting community resilience. We also discuss how volcanological expertise, which furnishes information on physical hazard processes and characteristics, can be interpreted to meet the social and psychological needs of community members and used to more effectively mitigate hazard consequences.
Community Preparedness and Response
Assessing risk solely from a physical perspective fails to accommodate community perceptions, resulting in problems communicating hazard information and undermining the adoption of mitigation measures (Johnston et al., 1999; Johnston & Paton, 1998; Mileti & Fitzpatrick 1993; Mileti & Sorensen 1990; Perry & Lindell 1990). While the essential components of risk education programs are well documented (Johnston & Ronan, 1999; Mileti & Darlington, 1997; Mileti & Fitzpatrick, 1992; Ronan & Johnston, 1998), their effectiveness will ultimately be a function of how well they accommodate the demographic and dispositional diversity inherent within communities (Millar et al., 1999; Paton, Johnston & Houghton, 1998; Ronan & Johnston, 1997).
Although several studies have investigated community perceptions of volcanic hazards and risk in New Zealand, their occurrence during periods of quiescence at a volcano (e.g. Ponter et al. 1993, Johnston & Houghton 1995, Taranaki Regional Council 1995) made it difficult to assess the accuracy of these perceptions and the effectiveness of mitigation strategies. Johnston et al. (1999) utilized a unique and unplanned opportunity to assess the effects of a volcanic eruption on community perceptions of natural hazards and their consequences. The original survey, in the February prior to the 1995 eruption, conducted in the North Island towns of Hastings and Whakatane, assessed individuals' hazard knowledge, perceptions of volcanic risk, sources of volcanic hazard information, the perceived effectiveness of this information, and the perceived credibility of the sources. A second survey, in November 1995, assessed the influence of the 1995 Ruapehu eruption on these factors.
Prior to the eruptions, both communities' residents had limited knowledge of past volcanic events, few recalled specific volcanic hazard information, and few had sought such information prior to the 1995 Ruapehu eruption. This eruption resulted in a small increase in the numbers searching for information on volcanic hazards in both communities, primarily from friends and relatives, local authorities and scientific agencies. Community groups differed with respect to the agency to whom they attributed greatest credibility as providers of information and warnings. This analysis emphasised the importance of addressing local issues and the need for agencies to convey consistent messages (Johnston et al., 1999). Further, these data illustrated how community groups differed with respect to the media considered most salient. This fact should also be accommodated when issuing warnings and hazard information. A need for integrated planning, coordination of information collection and dissemination, and inter-organization communication to enhance the quality of community information provision was also indicated (Paton, et al., 1998; Paton et al., 1999).
While the survey data suggested that experiencing the 1995 Ruapehu eruption may make subsequent warnings and information releases more salient, so encouraging adoption of protective actions, this was more likely in those who experienced negative impacts. The relatively benign impacts of this eruption may, however, have resulted in the occurrence of an attributional process in the form of a "normalisation bias" (cf. Mileti & O'Brien, 1993). This describes how those who experience a rare and benign or minimally disruptive experience perceive this event as a norm for this class of experience. Subsequently, on the basis of this 'normative impact', they infer that future events will have little negative impact upon them or that they can be managed with existing resources or levels of preparedness (Paton et al., 1998). This may be more prevalent in those who experienced minimal or no ash effects as a consequence of favourable but chance wind directions, reinforcing the importance of communication accurate volcanological information to communities regarding the likely nature and consequences of different eruption scenarios. This is not to say that this eruption left all sections of the community unaffected. Indeed, children and those affected by economic fall-out from even low level hazard activity can be particularly vulnerable (Millar et al., 1999; Ronan, 1997a).
Ronan & Johnston (1999) found that a significant minority (just over 25%) of children self-reported moderate to severe indicators of eruption-related distress (see also Huzziff & Ronan, 1999; Ronan 1997a; Ronan, 1997b). For example, several populations (e.g., children with asthma, those with fewer social supports) were vulnerable to increased distress both initially and over time. In addition, children who reported hearing negatively valenced discussions about the eruptions at home, or who perceived their parents to be anxious about the eruptions, also reported problems (Ronan, 1997a). On the other hand, children who coped effectively were assisted by, for example, social support strategies including parents not engaging in upsetting discussions or demonstrating an ability to cope effectively (Huzziff & Ronan, 1999). An important factor assisting many distressed children was the dissemination of accurate volcanological information approximately three months after the eruption to dispel myths and uncertainties regarding the nature of the eruption and its effects.
Our model of preparedness and recovery includes the use of a multiple gating methodology (Johnston & Ronan, 1999; Long, Ronan, & Perreira-Laird, 1998; Ronan & Johnston, 1999). Multiple gating involves the efficient use of resources to assist the largest number of individuals possible within a parsimonious timeframe. For example, an early "gate" examined the effectiveness of brief, school-based intervention program aimed at helping reduce eruption-related distress, increasing coping ability, and providing accurate information (Ronan & Johnston, 1999).
Overall, the one hour intervention, presented three months after the first eruption episode, reduced distress and increased coping. In fact, children reported increased ability to cope with upsetting eruption-related stimuli (e.g., upsetting media coverage) more after the one hour program than was reported over the two month interval that preceded the intervention. These children continued to function more effectively four months after the intervention (seven months after the eruption) compared to a control group not exposed to the program. Those who do not make necessary would be followed up with more comprehensive assistance.
Other work has focused on the fact that community perceptions and response need not relate in a linear fashion to physical impact. Millar et al. (1999) identified differences in the perceived salience attributed to eruption-related consequences, with economic effects being perceived as more important than physical consequences per se. The information distributed to communities typically concerns, for example, ash and lahar threat. While this information remains important, its meaning for the community, and consequently its effectiveness in facilitating preventative measures, can be enhanced by presenting information about physical hazard activity in terms of its implications for salient community needs and functions (Paton et al., 1999).
Millar et al. (1999) found that impact was not distributed evenly amongst all groups within the community. For example, because ash effects were restricted to high mountain slopes, those reliant upon winter sports were more vulnerable than those involved in farming. It is also interesting to note that if this eruption had occurred during the summer months it would have had less negative effects, and may even have represented a net gain to the surrounding communities from increased tourism. An important conclusion here is that information and response plans must be designed to manage specific, and often diverse, community needs (Johnston & Ronan, 1999; Millar et al., 1999). Generic plans, or those based upon inappropriate assumptions of community heterogeneity, will be less effective. We must also acknowledge the complexity introduced into this process by the fact that communities have access to several sources of information.
Scientific Information, the Media and Social Amplification
The media and the public will experience volcanic hazards directly and receive information about what is happening from several sources. Understanding the mediating role the media can play in this context is important because of the accessibility of media information. A failure to provide the media with accurate and timely information can create problems for scientific and other response agencies if the public assign greater salience to media coverage.
A crucial issue here is the concept of the social amplification of risk (Kasperson, 1992). During the 1995-1996 eruptions, inaccurate media reporting of volcanic hazard effects and their implications resulted in the "social amplification" of perceived community risk and heightened anticipatory anxiety in surrounding communities (Johnston & Paton, 1998; Johnston & Ronan, 1999; Ronan & Johnston 1996; 1999). For example, media coverage of the effects of the eruption undermined the effectiveness of school intervention programs and resulted in the social amplification of childrens' threat perceptions. To attenuate this problem, negotiation with the media to provide balanced coverage and additional work with schools was necessary (Ronan & Johnston, 1996; 1999). Managing this social amplification constituted a demand that both undermined earlier mitigation work and required that scarce resources be allocated to dealing with a problem that had already been contained. It is thus essential that the planning process anticipates this problem and facilitates the development of sound media and community information management. We must also accommodate the fact that we as scientists can influence the media when reporting on events. This underscores the need to develop media relationships to help attenuate social amplification problems and allow media resources to be harnessed to assist reduction and response management.
Managing the social amplification process may also enhance public perceptions of, and the credibility of, scientific, government, and response agencies, increase the accessibility of scientific information, and increase the likelihood that future warnings or information will be utilised in the manner intended. This, in turn, involves anticipating community and media needs, developing the means of their satisfaction, and providing timely, accurate and consistent information to communities prior to, during, and after an eruption (Paton et al., 1999).
Integrated Emergency Management: Utilising scientific information
The response to the 1995-1996 eruptions at Ruapehu volcano, New Zealand, provided an opportunity to examine the interaction between scientific agencies, primarily volcanologists and seismologists from the Institute of Geological and Nuclear Sciences (GNS), and response management agencies. Several communication problems emerged in this context (Paton et al., 1999).
These problems did not reflect inadequacies in the data furnished by GNS. Rather they were attributable to: a) the process of transforming data into understanding; and b) the assumptions made by response agencies regarding their information management capabilities. In raw form, volcanological and seismic data may have little intrinsic meaning for response agencies. Consequently, rendering data meaningful in the context of the decisions and response activities for which each agency is responsible represents a core managerial activity. Response agencies often presume that scientific sources will automatically provide for their information and decision needs. This is likely to be the exception rather than the rule for several reasons.
The low frequency of damaging eruptions, and the urgency and unpredictability of the demands eruptions make on volcanologists, makes it imperative that scientific agencies concentrate on their core business of monitoring and measuring eruptions effects and directing their scarce resources to developing our understanding of the hazard phenomena to be managed rather than translating data for diverse agencies with wide-ranging information needs. Under these circumstances, scientific resources will be unable to deal with new or unanticipated requests for assistance and information. Consequently, response agencies must have well developed networks, information management systems, and interpretative capabilities prior to an eruption occurring (Paton et al., 1999).
The development of this capability is also essential for managing the information and decision needs that emerge when managing disparate hazard consequences and the geographical and temporal changes in the nature of hazard effects. For instance, several agencies require data on ash thickness and composition. Different agencies, however, use these data for different functions. For example, conservation (effects on rare plants, tourist movements), utility (effect on power/water supply), agriculture (effect on crops, livestock), civil aviation (effect on aircraft movement) and transit (effect on road/rail networks) agencies must interpret ash data to meet their specialised information and decision needs (Paton et al., 1999). Geographical factors (e.g., changes in ash thickness with distance from source, implications of interaction between ash and soils or water), temporal factors (e.g., ash threat affected by changing climatic conditions) and meteorological influences (e.g., wind speed and direction, humidity) contribute added complexity to the decision environment.
Scientific agencies do not possess the resources or expertise to respond to all the possible requests that could emerge within this decision environment. Response agencies must acknowledge that while scientific data may be readily accessible, rendering it into a meaningful format, and one that is consistent with their decision needs, is a function of the quality of the dialogue they have had with the geological community and their own interpretative and decision management capability, particularly in relation to the ability to access, collate, interpret and utilise scientific information (Paton et al., 1999).
With appropriate information and decision needs analysis, response agencies can identify their information needs and develop networks with the providers of scientific and specialist data. Implicit within this process is the development of an appreciation of, and an ability to manage, uncertainty inherent within scientific data and forecasts about the activity of complex and dynamic natural phenomena. Consequently, response agencies must accept that scientific data cannot be viewed as prescriptive, accommodate this uncertainty with their decision management, develop their interpretative capability accordingly, and accept that judgement will be required for decision making and determining appropriate actions. While the quality of data, with respect to its decision utility, may evolve through dialogue between volcanological and emergency management professionals, the complexity and uncertainty inherent within the phenomena being managed precludes the possibility of eliminating the need for interpretative and judgmental capability.
Managing Diversity: Group dynamics and integrated emergency management
The fact that the demands encountered when responding to a disaster transcend individual capabilities is recognised within the Integrated Emergency Management (IEM) philosophy, which defines effective disaster management as involving the collective and co-ordinated activities of several agencies and professionals, including volcanologists. Members of these organisations will be working collaboratively with agencies with whom they would have little or no contact with under normal circumstances.
The effective utilisation of diverse expertise requires the management of professional and dispositional diversity (Paton, Johnston, Houghton, & Smith, 1998; Paton & Flin, 1999). Effective integration in this context involves, for example, team development and management, negotiation about response roles and capabilities, the management of personal and professional diversity, and inter-agency training and communication (Paton & Flin, 1999). All agencies should be involved in the design and performance of exercises and simulations.
The adoption of an IEM philosophy has implications for the decision making procedures adopted to utilize data and information and expertise. For example, the scale and distribution of hazard impact and its multi-disciplinary and sometimes multi-jurisdictional implications signals a need for distributed decision making (Paton & Flin, 1999). Analysis of response to the 1995/96 eruption also highlighted the need for contingent decision making capabilities. When responding to volcanic crises, decision style will necessarily change with prevailing circumstances. During quiescent periods, or between eruption episodes, response plans can be carefully evaluated and compared, rendering analytical decision making appropriate. During eruption episodes, rapid decisions must be made within a short time frame, making naturalistic decision making more appropriate (Paton & Flin, 1999). Attention must be directed to understanding the data provided by volcanologists and modeling it in training simulations to develop contingent decision making capability.
Training is crucial to response effectiveness and should utilise an all-hazards approach to develop skills in information analysis, inter-agency communication, decision making, managing uncertainty, and communicating with the media and the public. Because opportunities to practice these skills are rare, planning must specify the activities necessary to realise the levels of expertise required for effective plan implementation. Training needs analysis will identify the demands, competencies and contextual constraints that must be modeled in emergency simulations (Paton, 1996; Paton & Flin, 1999). Simulations afford opportunities for emergency managers to review and develop plans, develop technical and management skills, practice their use under realistic circumstances, receive feedback on their performance, increase awareness of stress reactions, and facilitate rehearsal of strategies to minimise stress reactions. Critical and comprehensive process, content and performance evaluation should follow all simulations and training exercises.
The outcomes of our Ruapehu research program have shaped several multidisciplinary efforts. Although varied in content, these projects are unified by two common threads: research collaboration between psychologists and geologists, and the use of this collective expertise to assist communities, organizations, and individuals be better informed about and prepared for a future eruption. Ronan & Johnston (1998) found that the more scientific information people recalled combined with other factors (e.g., receiving specific guidance) related to increased levels of preparedness-related activity. Thus, our education programs will focus on including such factors to enhance effectiveness.
In addition to providing baseline data on levels of awareness and preparedness against which the effectiveness of future mitigation initiatives can be assessed, previous studies are helping to design models to predict the relationship between individual, community and organisational characteristics and vulnerability to hazard effects. These models can assist mitigation planning and the design of preparatory programs to foster action and commitment to adopting recommendations and to assist decision making regarding the allocation of scarce resources.
It is important to acknowledge that the provision of information alone, irrespective of its quality, need not guarantee the adoption and performance of mitigation measures. For example, while school hazard education programs do increase awareness, promote more realistic risk perceptions, reduce fears, increase hazard-related knowledge (e.g., protective behaviours, risk mitigation), and promote hazard-related discussions with parents, they do not demonstrate an ability to translate these benefits into actual prepardness-related behaviours (Ronan & Johnston, 1997). Similarly, provision of information to a community may increase awareness but have no influence on preparedness (Ballantyne et al., in prep). Indeed, the latter study found that increased awareness may lessen the perceived need for preparedness.
Encouraging sustained readiness and commitment to act requires not just different strategies, but also a different way of thinking about these issues (Paton, Smith, Violanti & Eranen, 2000). It requires a focus on understanding what constitutes resilience at several levels of analysis and a research and intervention paradigm that focused on growth and wellness (salutogenesis) rather than on loss and pathology (Violanti, Paton, & Dunning, 2000). For example, Millar et al. (1999) demonstrated how self-efficacy and problem-oriented coping constituted resilience factors and acted to reduce vulnerability to volcanic hazard consequences. An interesting issue here was the relationship between resilience and community participation. Programs that encourage community participation, whether concerned with hazard issues or not, can enhance resilience and, therefore, constitute a viable strategy for mitigating volcanic hazard consequences and/or help minimise their disruptive effects. This opens up several cost-effective mitigation possibilities that involve the promotion of community involvement well-being through community development activities. A second issue here concerns whether the paradigm within which these activities occur focus on pathological outcomes (e.g., actions intended to prevent destruction) or on sustainability and growth (e.g., action intended to promote quality of life or to add value to property or the environment). The latter provides a more positive framework and environment within which community members can engage in, and appreciate the benefits accruing from, mitigation activities (Paton, in prep).
In the context of increasing emphasis on integrated emergency management, hazard and risk management, and the development and maintenance of community resilience and sustainability, psychological input can contribute to the effective analysis and development of best practice in these areas. Psychologists can enhance the effective use of specialist and scientific knowledge and expertise at individual, community, and organisational levels by interfacing between scientific information providers and the communities and response agencies that require it to facilitate their resilience and CEM effectiveness. Specifically, organisational psychologists can contribute to this process through conducting training needs, information and decision analyses, multi-disciplinary team building, the management of diversity, and decision making. Clinical psychologists can direct the educational and recovery management needs of children and communities. Psychologists also have a role to play in assessing community information needs and the development of effective action-oriented mitigation programs. We are currently conducting information and decision needs analyses in scientific and response agencies to develop systems for reconciling these needs. Importantly, prominent funding agencies in New Zealand have confirmed their support for these efforts.
At a time when increasing emphasis is being placed on community resilience and sustainability, it is important that these constructs are operationalised in a manner that can serve to guide intervention development and administration. The attainment of these goals may be accomplished more readily if we shift the fundamental paradigm underpinning research and intervention away from one which embraces pathology and loss towards one which promotes growth and development.
Preparation of this manuscript was facilitated by a grant from the New Zealand Foundation for Research, Science, and Technology to the authors.
Ballantyne, M., Paton, D., Johnston, D., Kozuch, M., and Daly. M. (in prep) Communicating about volcanic hazards: Awareness, preparedness and action. Disaster Prevention and Management.
Huzziff, C. A. and Ronan, K. R., (1999) Prediction of children's coping following a natural disaster - the Mount Ruapehu eruptions: A prospective study. Australasian Journal of Disaster and Trauma Studies (on-line journal URL http://massey.ac.nz/~trauma/).
Johnston, D.M., Bebbington, M.S., Lai, C.-D. , Houghton, B.F., and Paton, D. (1999) Volcanic hazard perceptions: Comparative shifts in knowledge and risk. Disaster Prevention and Management. 8, 118-127.
Johnston, D.M., and Houghton, B.F. (1995) Secondary school children's perceptions of natural hazards in the central North Island, New Zealand. New Zealand Journal of Geography, 99, 18-26.
Johnston, D. M., Houghton, B. F., Neall, V.E., Ronan, K. R., and Paton, D. (in press) Impacts of the 1945 and 1995-1996 Ruapehu eruptions, New Zealand: An example of increasing societal vulnerability. Geological Society of America Bulletin.
Johnston, D. and Paton, D. (1998) Social amplification of risk: Transient end-points. In G.D. Lewis, N.G. Thom, J.E. Hay and K. Sukhia (eds) Risk Assessment of Environmental End Points. Auckland: University of Auckland.
Johnston, D. M. and Ronan, K. R. (1999) Risk education and intervention. In H. Siggurdsson (ed) Encyclopedia of Volcanoes New York: Academic Press.
Kasperson, R.E. (1992) The Social Amplification of Risk: Progress in developing an integrative framework. In S. Krimsky and D. Golding (Eds): Social Theories of Risk. London, Praeger.
Long, N. R., Ronan, K. R., and Perreira-Laird, J. (1998) Victims of disaster. In N. N. Singh (Ed.), Comprehensive clinical psychology: Applications in diverse populations. New York: Pergamon Press.
Mileti, D. S. and Darlington, J. D. (1997) The role of searching in shaping reactions to earthquake risk information. Social Problems, 44, 89-102.
Mileti, D.S. and Fitzpatrick, C. (1993) The Great Earthquake Experiment: Risk communication and public action. Westview Press, Boulder, Colorado, 140p.
Mileti, D.S. and O'Brien, P.W. (1993) Public response to aftershock warnings. U.S. Geological Survey Professional Paper 1553-B: B31-B42.
Mileti, D.S. and Sorensen, J. H. (1990) Communication of Emergency Public Warnings: A social science perspective and state-of-the-art assessment. Oak Ridge Laboratory ORNL-6609.
Millar, M., Paton, D. and Johnston, D. (1999) Community vulnerability to volcanic hazard consequences. Disaster Prevention and Management, 8, 255-260.
Paton, D. (1996) Training disaster workers: Promoting well-being and operational effectiveness. Disaster Prevention and Management, 5, 10 - 16.
Paton, D. (in prep) Promoting community resilience and growth: Paradigmatic change and strategies. Environmental Hazards.
Paton, D. and Flin, R. (1999) Disaster Stress: An emergency management perspective. Disaster Prevention and Management, 8, 261-267.
Paton, D., Johnston, D. and Houghton, B. (1998) Organisational responses to a volcanic eruption. Disaster Prevention and Management. 7, 5 - 13
Paton, D., Johnston, D., Houghton, B., and Smith, L.M. (1998) Managing the effects of a volcanic eruption: Psychological perspectives on integrated emergency management. Journal of the American Society of Professional Emergency Managers. 5, 59- 69.
Paton, D., Johnston, D., Houghton, B., Flin, R., Ronan, K., and Scott, B. (1999) Managing Natural Hazard Consequences: Information management and decision making. Journal of the American Society of Professional Emergency Managers, 6,
Paton, D., Smith, L.M., Violanti, J.M. and Eränen, L. (2000) Work-related Traumatic
Stress: Risk, vulnerability and resilience. In Violanti, J.M., Paton, D. and Dunning, C. (eds) Posttraumatic Stress Intervention: Challenges, Issues and Perspectives. Springfield, Ill., Charles C. Thomas.
Perry, R.W. and Lindell, M.K. (1990) Living with Mount St. Helens: human adjustment to volcano hazards. Washington University Press, Pullman, Washington, 205 p.
Ponter, D., Doorman, P. and Feist, R. (1993) Survey of attitudes and perceptions towards the environment in the Bay of Plenty. Bay of Plenty Regional Council Resource Planning Publication 21, 103 p.
Ronan, K. R. (1997a) The effects of a series of volcanic eruptions on emotional and behavioural functioning in children with athsma. New Zealand Medical Journal. 110, 11-13.
Ronan, K. R. (1997b) The effects of a "benign" disaster: Symptoms of posttraumatic stress in children following a series of volcanic eruptions. Australasian Journal of Disaster and Trauma Studies, 1 (on-line journal URL http://massey.ac.nz/~trauma/).
Ronan, K. R. and Johnston, D. M. (1996) The impact of volcanic eruptions on childhood emotional functioning. Proceedings of the Pan Pacific Hazards '96 Conference, 1 (CD-ROM). Vancouver: University of British Columbia.
Ronan, K. R. and Johnston, D. M. (1997) Auckland school children's risk perceptions and preparedness: Hazards education survey. Technical report prepared for Auckland Regional Council/Auckland City Council.
Ronan, K. R. and Johnston, D. M. (1999) Behaviourally-based interventions for children following volcanic eruptions: An evaluation of efficacy. Disaster Prevention and Management, 8, 169-176.
Ronan, K. R. & Johnston, D. M. (1998) A community's understanding of earthquake risk in the Manawatu. Technical report prepared for the New Zealand Earthquake Commission.
Taranaki Regional Council (1995) Civil Defence Survey: public awareness and preparedness report. Taranaki Regional Council, New Plymouth, New Zealand
Violanti, J.M., Paton, D. and Dunning, C. (2000) Posttraumatic Stress Intervention: Challenges, Issues and Perspectives. Springfield, Ill., Charles C. Thomas.