El Niño-Southern Oscillation: Related Probabilities of Fatalities from Natural Perils in Australia

The interannual variability of flood, bushfire andheatwave fatality data for eastern Australia duringthe period 1876–1991 was analysed with respect to thephase of the El Niño-Southern Oscillation (ENSO)and the associated values of the Southern OscillationIndex (SOI). Heatwaves were found to be the mostserious peril in terms of the total number offatalities, while floods ranked first in the fatalityevent day statistics. None of the three monthly(absolute value) fatality data sets showed significantcorrelations with the corresponding values of the SOI,while the correlation analysis of annual (July toJune) data led to significant correlation coefficientsof 0.5 for floods and -0.3 for bushfires. AdditionalSOI value-related classification of the standardisedfatality event days into several ENSO categoriesconfirmed the correlation trends by showing anincrease (decrease) in the standardised bushfire(flood) fatality event day frequencies with increasingvalues of the SOI. In contrast to that, thestandardised heatwave fatality data showed aninconclusive distribution pattern, which hints at theinfluence of other possible factors (such as airpollution) on heatwave-related fatality numbers.The results of a risk assessment analysis have shownthat the probability of reaching the mean annualnumber of flood-fatality event days is roughly fourtimes higher during La Niña seasons (80%) thanthe corresponding probability associated with ElNiño periods (18%). The correspondingprobabilities associated with the mean bushfire andheatwave fatality event days displayed a reversedpattern, with the probabilities of El Niño-relatedyears being roughly twice as high as those associatedwith La Niña seasons (70% and 30% for bushfires,and 60% and 25% for heatwaves, respectively).Further probability calculations performed on thetotals of fatalities from all three perils identifiedthe La Niña years as potentially the mostdangerous in terms of suffering fatalities from theseperils. Furthermore, they highlighted the significantdifferences between the means of fatality event daynumbers recorded during years of extreme SOI values(9.8 for La Niña, and 9.1 for El Niño seasons)and those marked by near-zero SOI values (6.6). Themajor reason for the increase in risk associated withextreme ENSO phases was the higher variability ofthese perils during the respective seasons.     

Fire intensity,slopewash and bio‐transfer of sediment in eucalypt forest,Australia

Sediment movement (slopewash and bio‐transfer), runoff, and organic matter movement (mainly leaf litter, ash and charcoal) were monitored on ten plots for a six‐month period following bushfires in eastern Australia in the 1990s. Plots were installed in areas which had experienced high, moderate and low intensity burns. Although between‐plot variability was high, slopewash and organic matter amounts were greatest on the intensely burnt areas, and progressively less on moderate and low intensity burns. In contrast, most leaf litter input from scorched leaf fall was derived from, and collected in, moderately burnt areas. Bio‐transfer of sediment (direct downslope surface movement produced by faunal activity) occurred mainly by ant mounding, and was more than ten times greater on moderately burnt areas than on plots having high or low intensity burns. Bio‐transfer accounted for approximately 36 per cent of total sediment collected, with this material being recorded least often and in smallest quantities on areas of high intensity burns. Bio‐transfer by ant mounding and animal scratchings contributed loose surface sediment for transport by overland flow, disproportionately increasing total sediment movement to plot aprons in areas of moderate intensity burns. Copyright © 2002 John Wiley & Sons, Ltd.     

Making the landscape “home”: Narratives of bushfire and place in Australia

This study investigated how the meaning of ‘home’ influences the social construction of bushfire in two Australian communities at high risk. An increasing number of Australians are living in proximity to areas of high bushfire risk due to climate, vegetation and demographic changes. Land and Fire Management Agencies recognise an urgent need to understand what motivates residents to take action to mitigate bushfire risk, and individual decisions whether or not to evacuate when bushfire is imminent. In bushfire policy and management, the home is considered to be synonymous with the house and associated built structures. Using a combination of visual and ethnographic research methods, we ‘mapped’ residents’ understanding of ‘home’. The findings suggest that the concept of ‘home’ embraces more than the private spaces of house and garden. Landscape practices such as gardening with indigenous plant species, ecological restoration, and habitual walking extend the home territory beyond the house and garden and into public landscapes. Physical elements of the landscape such as mountains and locally significant species of trees form part of the ‘imaginary’ of home. These findings are important to the on-going study of the meaning of home. The implications are also significant for land and bushfire managers as they suggest that community education programs that focus solely on the house may fail to connect with people’s wider sense of home in the landscape.     

Where's the Fire? Co-Constructing Bushfire in the Everyday Landscape

This research studied factors that residents of a fire-prone Victorian community used when deciding whether to leave their homes on a day officially declared “Catastrophic,” the highest Fire Danger Rating. Taking a social constructivist perspective, we explore how the expert view of bushfire risk, represented by Fire Danger Ratings, is interpreted within the context of local understandings of the landscape and social memory of bushfire. Residents perceive a disconnection between the Fire Danger Rating and local reality. Their social construction of bushfire is related to social and ecological memory, which comprises physical experience of the landscape and local fire knowledge narratives. The exclusion of this social complexity from Fire Danger Ratings diminished their utility as a way of helping people make meaning of bushfire. We propose that fire management agencies work with communities to develop a co-constructed view of bushfire risk that incorporates local bushfire knowledge into Fire Danger Ratings.     

Climate Change,Bushfire Risk,and Environmental Values: Examining a Potential Risk Perception Threshold in Peri-Urban South Australia

Striking a balance between the management of environmental risks and values is a challenge for decision-makers. If people perceive that environmental risks are increasing they may be willing to discount local values to manage those risks, so the identification of thresholds in risk perception in relation to specific behaviors could help to avoid policy failures. The complex relationships between perceptions of climate change and bushfire risks, environmental values and support for actions to mitigate local risks are presented for peri-urban regions in South Australia. The results of a household survey (N=988) suggest that a threshold of risk perception in relation to climate change and bushfire management has not been exceeded and people are broadly supportive of balanced management interventions. A minority of people still do not perceive that climate change is increasing bushfire risk, and are supportive of risk mitigation interventions even at the expense of local biodiversity. However, a larger group believe that climate change is a driver of bushfire risk, yet are still more likely to prioritize ecological values and are unwilling to discount those values for risk mitigation. Targeted communication could assist different groups to respond to gaps in knowledge and action to facilitate effective, differentiated interventions within forested landscapes on the margins of urban areas.     

森林火灾对典型小流域径流影响模拟

以澳大利亚东南部Mcmahons Creek 流域1983年发生的森林火灾为例,运用AWRA-L和新安江模型模拟火灾后流域的基准径流过程,进而估算火灾对径流的影响。AWRA-L和新安江模型模拟结果表明,火灾发生后14年(1983—1997年)内流域产水量分别增加140 mm和123 mm,占火灾前(1974—1982年)年均径流量的33%和29%;火灾发生14年后的1998—2004年,增加量分别为43 mm和33 mm,占火灾前年均径流量的10%和8%。说明森林火灾引起短期内流域径流量的明显增加,随着植被的恢复流域产流增加量减少,森林砍伐是后期径流增加的重要原因。该研究对森林流域的水资源管理具有重要的参考价值。     

Trial by Fire: natural hazards,mixed-methods and cultural research

This paper considers the issues of research ‘relevance’ and ‘use’ to reflect upon a cultural geography research project on bushfire that did not begin with any specific aim of being useful to policy makers but which has garnered considerable and ongoing interest from a broad audience. It provides an example of how the integration of quantitative and qualitative research methods and data can enhance research into cultural aspects of natural hazards whilst simultaneously playing a key role in ensuring that the research results are of interest to a wide range of groups. Using a mixed-methods research approach was found to provide insight into complex factors that influence attitudes and actions towards bushfire amongst diverse landholders in rural–urban interface areas in south-east Australia. We argue that mixed-methods research is a powerful tool in building and enhancing a cultural geography that has policy relevance, retains analytical depth, and is acceptable to risk managers. The ability of cultural geography through mixed-methods research to illuminate how socio-cultural processes are central to environmental attitudes and preparedness behaviour has direct relevance to recent international discussions of how to manage the vulnerability of the growing number of people living in bushfire-prone rural–urban interface areas.     

Environmental hazards and natural disasters

How can the apparently growing frequency and cost of environmental hazards be explained? Drawing on a range of examples, and especially the Canterbury earthquakes, it is argued that the creation of knowledge about these events depends on the interplay of lived and historical experience with scientific awareness. But often the vulnerability of places to particular events is obscured by popular use of the terms ‘natural hazard’ or ‘natural disaster’, as if human behaviour is absolved from any responsibility. It is shown how such thinking often increases the extent of the hazard, so that although we do not cause earthquakes, floods and bushfires, we are implicated and complicit in the outcomes.