IPCC_Managing Risks of Extreme Events.pdf - Climate Access

Toward a Sustainable and Resilient FutureChapter 8waste, and energy) intimately connect rural and urban economies andsocieties, and the local with the global, such that the sustainability ofone will influence the other. The existence of multiple, intersectingstressors in rural and urban contexts draws attention to the importanceof addressing the underlying drivers of risk as a means of both disasterrisk management and adaptation, and of promoting climate changemitigation.8.6. Options for Proactive, Long-TermResilience to Future Climate ExtremesConsidering the broad challenges described previously, it is importantto assess the range of existing planning tools and the ways they areused, who uses them, and how they interact or change over time.Pursuing sustainable and resilient development pathways requiresintegrated and ambitious policy that is science-based and knowledgedriven,and that is capable of addressing issues of heterogeneity andscale. The latter issues are particularly vexing, as the consequences of,and responses to, extreme climate and weather events are local, butthese responses need to be supported and enabled by actions at regional,national, and global scales.This section first considers the challenges of planning for the future,then assesses the literature pertaining to tools and practices that canhelp address these issues. As the preceding sections in this chapter andother chapters in the report have argued, achieving a sustainable andresilient future draws attention to the need for both incremental andtransformational changes. Based on an assessment of the literature, thefinal section discusses why such changes may involve a combination ofadaptive management, learning, innovation, and leadership.8.6.1. Planning for the FutureDisaster risk management and climate change adaptation arefundamentally about planning for an uncertain future, a process thatinvolves combining one’s own aspirations (individual and collective)with perspectives on what is to come (Stevenson, 2008). Planning forthe future is challenging when the stakes are high, values disputed,and decisions urgent, and these factors often create tensions amongdifferent visions of development. Typically, decisionmakers (representinghouseholds, local or national governments, international institutions,etc.) look to the future partly by remembering the past (e.g., projectionsof the near future are often derived from recent experiences with extremeevents) and partly by projecting how the future might be different(using forecasts, scenarios, visioning processes, or story lines – eitherformal or informal) (Miller, 2007). Projections further into the future arenecessarily shrouded in larger uncertainties. The most commonapproach for addressing these uncertainties is to develop multiplevisions of the future (quantitative scenarios or narrative storylines), thatin early years can be compared with actual directions of change(Boulanger et al., 2006a,b; Moss et al., 2010).Scenario development has become an established research tool both inthe natural sciences (e.g., Nakicenovic et al., 2000; Lobell et al., 2008)and in the social sciences (e.g., Wack, 1985; Davis, 1998; Robinson,2003; Galer, 2004; Kahane, 2004; Rosegrant et al., 2011). Scenarios canbe based on different spatial (e.g., global, national, and local) andtemporal scales (e.g., from a few years to several decades or centuries).The challenges for integrated disaster risk management and climatechange adaptation scenarios are to generate climate data that can bedownscaled to at least regional and sub-national scales, while extendingdisaster risk projections to longer time scales (see Gaffin et al., 2004;Theobald, 2005; Bengtsson et al., 2006; van Vuuren et al., 2006; Grübleret al., 2007; Moss et al., 2010; Hallegatte et al., 2011a).Scenario development has traditionally been carried out in a sequentialmanner (Moss et al., 2010). For example, a first step in developing climatechange scenarios has typically involved structural projections of keydeterminants of greenhouse gas emissions (e.g., population changes,urbanization, etc.). These have been used to estimate concentrationsand radiative forcing from emissions, leading to climate projections thatcan be used in impacts research. One difficulty in using climate scenariosfor disaster risk management and climate change adaptation has beenthe uncertainties associated with extreme climate and weather events,including the behavior of local climates (see Section 3.2.3). Futuresocioeconomic changes (e.g., demography, population preferences,technologies) are also highly uncertain, thus scenarios must consider awide range of possible futures to design adaptation strategies andanalyze tradeoffs (e.g., Hall, 2007; Lempert, 2007; Lempert and Collins,2007; WGBU, 2008; Dessai et al., 2009a,b; Hallegatte, 2009). Alternativeapproaches have focused first on scenarios of radiative forcing, followedby an analysis of the combinations of economic, technological,demographic, policy, and institutional factors that can influence suchtrajectories (Moss et al., 2010). Other approaches are based on robustdecisionmaking (e.g., Groves and Lempert, 2007; Lempert and Collins,2007; Groves et al., 2008); information gap analysis (Hine and Hall,2010); or on the search for co-benefits, no regrets strategies, flexibility,and reversibility (e.g., Fankhauser et al., 1999; Goodess et al., 2007;Hallegatte, 2009).Scenario development requires substantial climate, social, environmental,and economic data, which are not equally available or accessible for allparts of the world. Qualitative scenarios can also be produced based onexpert judgment (e.g., Delphi exercises) or on storylines designed throughconsultative processes. Such scenarios often reflect different mindsetsor worldviews that represent contrasting visions of the future.To adapt to changing climate and weather extremes, difficult choicesmay become increasingly necessary. In many locations, for example,adapting to scenarios of reduced water availability may involveincreased investments in water infrastructure to provide enoughirrigation to maintain existing agricultural production, or a shift fromcurrent production to less water-consuming crops (see Rosenzweig etal., 2004; ONERC, 2009; Gao and Hu, 2011). In considering adaptationto future flood risk in the Thames Estuary, the UK Environment Agency462