IPCC_Managing Risks of Extreme Events.pdf - Climate Access

Case StudiesChapter 9preparedness centered on engaging with communities results inincreased awareness compared with top-down messages (Smoyer-Tomic and Rainham, 2001).9.2.1.5.4. Adapting the urban infrastructureSeveral types of infrastructural measures can be taken to preventnegative outcomes of heat-related extreme events. Models suggest thatsignificant reductions in heat-related illness would result from land usemodifications that increase albedo, proportion of vegetative cover,thermal conductivity, and emissivity in urban areas (Yip et al., 2008;Silva et al., 2010). Reducing energy consumption in buildings can improveresilience, since localized systems are less dependent on vulnerableenergy infrastructure. In addition, by better insulating residentialdwellings, people would suffer less effect from heat hazards. Financialincentives have been tested in some countries as a means to increaseenergy efficiency by supporting those who are insulating their homes.Urban greening can also reduce temperatures, protecting local populationsand reducing energy demands (Akbari et al., 2001).9.2.1.6. Lessons IdentifiedWith climate change, heat waves are very likely to increase in frequencyand severity in many parts of the world (Section 3.3.1). Smarter urbanplanning, improvements in existing housing stock and critical infrastructure,along with effective public health measures will assist in facilitating climatechange adaptation.Through understanding local conditions and experiences and current andprojected risks, it will be possible to develop strategies for improvingheat preparedness in the context of climate change. The specificity ofheat risks to particular sub-populations can facilitate appropriateinterventions and preparedness.Communication and education strategies are most effective when theyare community-based, offer the opportunity for changing social norms,and facilitate the building of community capacity.Infrastructural considerations are critical to reducing urban vulnerabilityto extreme heat events. Effective preparedness includes building techniquesthat reduce energy consumption and the expansion of green space.Heat wave preparedness programs may be able to prevent heat mortality;however, testing and development is required to assess the most effectiveapproaches.Further research is needed on the efficacy of existing plans, how toimprove preparedness that specifically focuses on vulnerable groups,and how to best communicate heat risks across diverse groups. Thereare also methodological difficulties in describing individual vulnerabilitythat need further exploration.9.2.2. Response to Disaster Induced byHot Weather and Wildfires9.2.2.1. IntroductionClimate change is expected to increase global temperatures and changerainfall patterns (Christensen et al., 2007). These climatic changes willincrease the risk of temperature- and precipitation-related extremeweather and climate events. The relative effects will vary by regions andlocalities (Sections 3.3.1, 3.3.2, and 3.5.1). In general, an increase inmean temperature, and a decrease in mean precipitation can contributeto increased fire risk (Flannigan et al., 2009). When in combination withsevere droughts and heat waves, which are also expected to increasein many fire regions (Sections 3.3.1 and 3.5.1), fires can becomecatastrophic (Bradstock et al., 2009). Wildfires occur in many regions ofthe world, and due to their extreme nature, authorities and the public ingeneral are acquainted with such extreme situations, and plans havebeen enacted to mitigate them. However, at times, the nature of firechallenges these plans and disasters emerge. This case study uses theexample from Victoria, Australia, in 2009. The goal is to present hotweather and wildland fire hazards and their effects and potentialimpacts, and to provide an overview of experience to learn to managethese extreme risks, as well as key lessons for the future.9.2.2.2. BackgroundWildfire risk occurs in many regions of the globe; however embodying thisrisk in a single and practical universal index is difficult. The relationshipsbetween weather and wildfires have been studied for many areas of theworld; in some, weather is the dominant factor in ignitions, while inothers, human activities are the major cause of ignition, but weather andenvironmental factors mainly determine the area burned (Bradstock et al.,2009). Wildfire behavior is also modified by forest and land managementand fire suppression (Allen et al., 2002; Noss et al., 2006). Wildfires donot burn at random in the landscape (Nunes et al., 2005), and occur atparticular topographic locations or distances from towns or roads(Mouillot et al., 2003; Badia-Perpinyà and Pallares-Barbera, 2006;Syphard et al., 2009). The intensity and rate of spread of a wildfire isdependent on the amount, moisture content, and arrangement of finedead fuel, the wind speed near the burning zone, and the terrain andslope where it is burning. Wildfire risk is a combination of all factors thataffect the inception, spread, and difficulty of fire control and damagepotential (Tolhurst, 2010).9.2.2.3. Description of EventsAn episode of extreme heat waves began in South Australia on 25January 2009. Two days later they had become more widespread oversoutheast Australia. The exceptional heat wave was caused by a slowmovinghigh-pressure system that settled over the Tasman Sea, incombination with an intense tropical low located off the northwest496