Russell Blong

The 2003 Heat Wave in France: Dangerous Climate Change Here and Now

In an analysis of the French episode of heat wave in 2003, this article highlights how heat wave dangers result from the intricate association of natural and social factors. Unusually high temperatures, as well as socioeconomic vulnerability, along with social attenuation of hazards, in a general context where the anthropogenic contribution to climate change is becoming more plausible, led to an excess of 14,947 deaths in France, between August 4 and 18, 2003. The greatest increase in mortality was due to causes directly attributable to heat: dehydration, hyperthermia, heat stroke. In addition to age and gender, combinatorial factors included preexisting disease, medication, urban residence, isolation, poverty, and, probably, air pollution. Although diversely impacted or reported, many parts of Europe suffered human and other losses, such as farming and forestry through drought and fires. Summer 2003 was the hottest in Europe since 1500, very likely due in part to anthropogenic climate change. The French experience confirms research establishing that heat waves are a major mortal risk, number one among so-called natural hazards in postindustrial societies. Yet France had no policy in place, as if dangerous climate were restricted to a distant or uncertain future of climate change, or to preindustrial countries. We analyze the heat waves profile as a strongly attenuated risk in the French context, as well as the causes and the effects of its sudden shift into amplification. Research and preparedness needs are highlighted.

MCE-RISK : integrating multicriteria evaluation and GIS for risk decision-making in natural hazards

Abstract During the past two decades there have been a wide range of applications for decision-making linking multicriteria evaluation (MCE) and geographic information systems (GIS). However, limited literature reports the development of MCE-GIS software, and the comparison of various MCE-GIS approaches. This paper introduces an MCE-GIS program called MCE-RISK for risk-based decision-making. It consists of a series of modules for data standardisation, weighting, MCE-GIS methods, and sensitivity analysis. The program incorporates different MCE-GIS methods, including weighted linear combination (WLC), the technique for order preference by similarity to ideal solution (TOPSIS), and compromise programming (CP), enabling comparisons between different methods for the same decision problem to be made. An example of decision-making for determining priority areas for a bushfire hazard reduction burning is examined. After implementing the alternative MCE-GIS methods, and comparing final outputs and the computational difficulty involved in the analysis, WLC is recommended. Some caveats on using MCE-GIS methods are also discussed. Although the development of MCE-RISK and its application reported in this paper are specific to risk-based decision-making in natural hazards, the program can be used for other environmental decision applications, such as environmental impact assessment and land-use planning.

A New Damage Index

A new damage index to estimate damage to buildings relies on construction costs per square metre, and a replacement ratio which approximates costs relative to the cost of replacing a median-sized family home. Building damage is estimated against a five-point scale with Central Damage Values at 0.02, 0.1, 0.4, 0.75 and 1.0 of the replacement cost.Damage is expressed as damage in House Equivalents (HE) = Replacement Ratio × Central Damage Value. The Damage Index = log2 (HE) provides a simple 0–20 scale covering total damage of less than 1 HE to>1 million HE. For all natural hazard impacts in Australia DI is less than 12.Where the only damage data available are of lesser quality Generic or Qualitative Damage Indices (GDI and QDI) can be used. The various advantages and limitations of the Damage Index are discussed.

Rabaul Caldera, Papua New Guinea: Volcanic hazards, surveillance, and eruption contingency planning

Abstract Planning for volcanic contingencies at the Rabaul caldera complex is a difficult task, requiring urgent attention in view of the results of volcano surveillance and historical eruption frequency. Historical eruption periodicities have ranged from about 2 to 59 years; the most recent eruptions were in 1937–1943 and caused more than 500 fatalities in May 1937. Surveillance since 1971 has revealed uplift of part of the caldera floor and increasing seismicity in a ring structure believed to define the caldera bounding fault or faults. These phenomena are interpreted as the prelude to a possible eruption. Potential eruption sites are all close to Rabaul town and outlying residential areas, and include the volcanoes of Sulphur Creek (last active about 1850), Vulcan and Tavurvur (1937–1943), and Rabalanakaia, but new sites should also be considered in relation to the results of volcano surveillance. A wide range of volcanic hazards accompanying different scales of eruption must be considered for the Rabaul area. The most likely types of eruption may be similar to the relatively small events that have been witnessed over the last century whose hazards included air-fall tephra, pumice rafts, pyroclastic flows and surges, volcanic earthquakes, volcanic-gas discharges, tsunamis, lightning strikes, and the fall of mud-rain, torrential run-off, and mudflows as a result of accompanying rain storms. Other potential eruption types of much larger scale could involve cauldron subsidence which could cause destructive tsunamis and could be accompanied by explosive activity of major proportions. Air-fall tephra is considered to be one of the main hazards from a future eruption, and its effects in and around Rabaul are primary influences in the choice of evacuation routes and points of refuge. Hence, theoretical tephra dispersal patterns have been considered in some detail. Air-fall tephra deposition from Rabaul eruption clouds at heights of less than about 4 km is determined by a biannual change in wind direction from southeast in May to October/November (trade winds) to northwest during the monsoon from December to March/April. In contrast, clouds that rise higher than about 4 km are blown by east winds all year round. Another principal hazard is pyroclastic flows and surges, which took place during the 1937 Vulcan eruption, but have until recently been overlooked, although flows or surges (or both) are clearly distinguishable on eruption photographs. The lack of suitable evacuation routes and problems in choosing safe and reasonably accessible refuge points compound the difficulties in preparing a practicable contingency plan. However, in small—moderate eruptions the safest areas around Rabaul are considered to be at the Duke York Islands, about 30 km to the east, and at Cape Gazelle, about 25 km to the southeast. Seaborne evacuation to main ports in central New Britain or on the neighbouring islands of New Ireland and Bougainville, or overland evacuation using a southwards-expanded road system, would be necessary in the event of forewarning of a major eruption.

Accounting for variability in commercial flood damage estimation

Flooding in the business district of Kempsey, New South Wales, Australia, in 2001 allowed the collection and analysis of commercial flood damage data. Analysis indicated that direct losses were significant, totalling A

Lightning fatalities in Australia, 1824-1991

2.5 million. Data were variable owing to differences in the vulnerability of businesses to flood damage, differences in the impacts of the hazard upon businesses and survey uncertainty. Little direct relationship was found between direct commercial damage and over-floor water depth. Simple averaging and stage-damage curve loss estimation methods ignore the large variability present and result in inaccurate estimation of direct commercial damage. Probability loss estimation methods account for the variability present by assessing the chance of loss values occurring at specified depths of over-floor flooding.

Regional ash fall hazard I: A probabilistic assessment methodology

Information on fatalities from lightning strikes has been extracted from a specially compiled database on natural hazards in Australia. Records dating from 1803–1991 indicate that at least 650 persons have been killed by lightning strikes. Maps and charts show the percentages of victims with respect to age, sex, locality, activity, and other circumstances of the strike. The majority of the 650 fatalities recorded have occurred along the more populous southeastern coast. The overall death rate, from 1910–1989, is 0.08 per 100 000 population. The annual number of lightning fatalities has decreased with time, from a death rate of 0.21 in 1910–1919 to 0.01 in 1980–1989. This trend is more pronounced when population figures are taken into account. The group that has been most at risk in Australia is that of males aged 15–19, followed by males aged 20–34. The male:female ratio of victims has decreased with time but is not approaching equality, being 11.6 in 1910–1919 and 5.3 in 1980–1989. The diurnal and monthly occurrences of lightning fatalities peak at 12.00–18.00 hours and November-February respectively. About 86% of fatalities have occurred outdoors and 14% have occurred indoors. Approximately three-fifths of fatalities have been work-related, and the group of workers that has traditionally been most at risk is that of land-workers. Approximately one-fifth of fatalities have been recreation-related, although this proportion has been increasing with time. The recreational activities of water sports, golf, and cricket have had the greatest number of lightning fatalities. Comparisons are made between these data and the results of other similar studies, both in Australia and overseas.

Fiji's worst natural disaster : the 1931 hurricane and flood

Volcanic ash is one of the farthest-reaching volcanic hazards and ash produced by large magnitude explosive eruptions has the potential to affect communities over thousands of kilometres. Quantifying the hazard from ash fall is problematic, in part because of data limitations that make eruption characteristics uncertain but also because, given an eruption, the distribution of ash is then controlled by time and altitude-varying wind conditions. Any one location may potentially be affected by ash falls from one, or a number of, volcanoes so that volcano-specific studies may not fully capture the ash fall hazard for communities in volcanically active areas. In an attempt to deal with these uncertainties, this paper outlines a probabilistic framework for assessing ash fall hazard on a regional scale. The methodology employs stochastic simulation techniques and is based upon generic principles that could be applied to any area, but is here applied to the Asia-Pacific region. Average recurrence intervals for eruptions greater than or equal to Volcanic Explosivity Index 4 were established for 190 volcanoes in the region, based upon the eruption history of each volcano and, where data were lacking, the averaged eruptive behaviour of global analogous volcanoes. Eruption histories are drawn from the Smithsonian Institution’s Global Volcanism Program catalogue of Holocene events and unpublished data, with global analogues taken from volcanoes of the same type category: Caldera, Large Cone, Shield, Lava dome or Small Cone. Simulated are 190,000 plausible eruption scenarios, with ash dispersal for each determined using an advection–diffusion model and local wind conditions. Key uncertainties are described by probability distributions. Modelled results include the annual probability of exceeding given ash thicknesses, summed over all eruption scenarios and volcanoes. A companion paper describes the results obtained for the Asia-Pacific region

A geography of natural perils

At least 225 people in the Fiji Islands died as a result of the 1931 hurricane and flood, representing the largest loss of life from a natural disaster in Fijis recent history. This paper explores the causes of disaster and the potential for recurrence. The disaster occurred because a rare event surprised hundreds of people-especially recently settled Indian farmers-occupying highly exposed floodplains in north-west Viti Levu island. The likelihood of a flood disaster of such proportions occurring today has been diminished by changed settlement patterns and building materials; however, a trend towards re-occupancy of floodplains, sometimes in fragile dwellings, is exposing new generations to flood risks. The contribution of this paper to the global hazards literature is set out in three sections: the ethnicity, gender and age of flood fatalities; the naturalness of disasters; and the merit of choice and constraint as explanations for patterns of vulnerability.

March 1990 Hailstorm Damage in Sydney, Australia

Abstract Earthquakes, tropical cyclones and floods are the most important natural perils in terms of human deaths on a global basis. In Australia, at least 4300 deaths in the last 200 years have been produced by heatwaves; about 2000–2200 each by tropical cyclones and floods; and bushfires and lightning strikes have each killed at least 650 people. On a global basis it appears that floods, tropical storms, droughts and earthquakes are the most damaging natural perils. In Australia, in terms of median damage per event, hailstorms are the most expensive insured natural peril, while three events—the 1989 Newcastle earthquake, 1974s Cyclone Tracy, and the 1990 Sydney hailstorm—produced 36 per cent of the total insured damage in the period since 1967. The Newcastle earthquake and the Sydney hailstorm have provided opportunities for new understandings of these perils and their consequences. While much has been learnt from the devastation of Rabaul town by the 1994 eruption, a rare opportunity for a detailed st...