IPCC_Managing Risks of Extreme Events.pdf - Climate Access

Chapter 6National Systems for Managing the Risks from Climate Extremes and Disastersabout future climate change events, investigation of the links betweensoft and hard engineering solutions, and strengthened research effortsto improve the modeling of small-scale climate events (Wilby, 2007;Auld, 2008b; Stevens, 2008).The recommended national adaptation options to deal with projectedimpacts to the built environment range from deferral of actions pendingdevelopment of new climate change information to modification ofinfrastructure components according to national guidance, acceptance ofresidual losses, reliance on insurance and other risk transfer instruments,formalized asset management and maintenance, mainstreaming intoenvironmental assessments, new structural materials and practices,improved emergency services, and retrofitting and replacement ofinfrastructure elements (Bourrelier et al., 2000; Auld, 2008b; Stevens,2008; Haasnoot et al., 2009; Hallegatte, 2009; Neumann, 2009; Kwadijket al., 2010; Wilby and Dessai, 2010).Strategic environmental assessment approaches, such as thoserecommended by the Organisation for Economic Cooperation andDevelopment (OECD) and many national environmental assessmentagencies, offer an effective means for ensuring that adaptation to climatechange and disaster risk management, as well as GHG reduction practices,are mainstreamed into policies and planning for new programs oninfrastructure and systems (OECD, 2006; Benson, 2007). Environmentalimpact assessment approaches can reduce the risks of environmentaldegradation from a project and reduce future disaster risks from currentand changing climate conditions (Benson, 2007). For long-livedinfrastructure or networks, studies recommend consideration of likelyclimate change impacts that will potentially affect the planned usefullife of the infrastructure system (e.g., seasonal variability in water flows,temperatures, incidence of extreme weather events) (OECD, 2006;Bosher et al., 2007; Auld, 2008b; Larsen et al., 2008; Neumann, 2009;NRTEE, 2009).The implementation of adequate national building codes that incorporateup-to-date regionally specific climate data and analyses can improveresilience of infrastructure for many types of weather-related risks(Auld, 2008b; WWC, 2009; Wilby et al., 2009). Typically, infrastructurecodes and standards in most countries use historical climate analyses toclimate-proof new structures, assuming that the past climate can beextrapolated to represent the future. For example, water-relatedengineering structures, including both disaster-proofed infrastructureand services infrastructure (e.g., water supply, irrigation and drainage,sewerage, and transportation), are typically designed using analysis ofhistorical rainfall records (Ruth and Coelho, 2007; Auld, 2008b;Haasnoot et al., 2009; Hallegatte, 2009; Wilby and Dessai, 2010). Sinceinfrastructure is built for long life spans and the assumption of climatestationarity will not hold for future climates, it is important that nationalclimate change guidance, tools, and consistent adaptation options bedeveloped to ensure that climate change can be incorporated intoinfrastructure design (Auld, 2008b; Stevens, 2008; Hallegatte, 2009;Wilby et al., 2009). While some government departments responsible forbuilding regulations and the insurance industry are taking the reality ofclimate change very seriously, challenges remain about how toincorporate the uncertainty of future climate projections into engineeringrisk management and into codes and standards, especially for climateelements such as extreme winds and extreme precipitation and theirvarious phases (e.g., short- and long-duration rainfalls, freezing rain,snowpacks) (Sanders and Phillipson, 2003; Auld, 2008b; Haasnoot et al.,2009; Hallegatte, 2009; Kwadijk et al., 2010; Wilby and Dessai, 2010; Lu,2011). Recent advances in characterizing the uncertainties of climatechange projections, in regionalization of climate model outputs, and inthe application and mainstreaming of integrated top-down, bottom-upapproaches for assessing impacts and adaptation options (Sections6.3.1 and 6.3.2) will help to ensure that infrastructure and technologycan be better adapted to a changing climate. Sections 3.2.3, 3.3, and 3.4provide further details on scientific advances for the construction,assessment, and communication of climate change projections, includinga discussion on recent advances in the development of regionalizationor downscaling techniques and approaches used to quantify uncertaintiesin climate change model outputs.Some implementation successes are emerging. In one example, discussedin Case Study 9.2.10, the Canadian Standards Association (CSA) and itsNational Permafrost Working Group developed a Technical Guide, CSAPlus 4011-10, on Infrastructure in Permafrost: A Guideline for ClimateChange Adaptation, that directly incorporated climate change temperatureprojections from an ensemble of climate change models. This CSA Guideconsidered climate change projections of temperature and precipitationand incorporated risks from warming and thawing permafrost tofoundations over the planned life spans of the structure (Hayley andHorne, 2008; NRTEE, 2009; CSA, 2010a; Smith et al., 2010; Grosse et al.,2011). The guide suggested possible adaptation options, taking intoaccount the varying levels of risks and the consequences of failure forfoundations of structures, whether buildings, water treatment plants,towers, tank farms, tailings ponds, or other infrastructure (NRTEE, 2009;CSA, 2010a; see Case Study 9.2.10). Similarly, working with the Canadianmeteorological service, engineering associations, and national waterstakeholder associations, the CSA has also developed an initial rainfallIntensity-Duration-Frequency Guideline for water practitioners withadaptation guidance (CSA, 2010b).In developing countries, structures are often built using prevalent localpractices, which may not reflect best practices from disaster risk reductionor adaptation perspectives. These prevalent local practices usually donot include the use of national building standards or adequatelyaccount for local climate conditions (Rossetto, 2007). While the perceptionin some developing countries is that national building codes and standardsare too expensive, experience in the implementation of incrementalhazard-proof measures in building structures has proven in some countriesto be relatively inexpensive and highly beneficial in reducing losses(Rossetto, 2007; ProVention, 2009). In reality, the most expensivecomponents of codes and standards are usually the cost to implementnational policies for inspections, knowledge transfer to trades, andnational efforts for their uptake and implementation (Rossetto, 2007).Bangladesh, for example, has implemented simple modifications to367