Seite - 320 - in Loss and Damage from Climate Change - Concepts, Methods and Policy Options

320 L.Schäfer et al. Box13.1Barriersand limits toadaptation throughthe lensof riskpreferences. Assuming that risk tolerance is socially constructed,Klinke andRenn (2002) suggest that actors evaluate risks based on one of three categories according to which they decide if the risks need to bemanaged or not: acceptable, tolerable, and intolerable. Acceptable risks are low-complex,well understood risks that are deemed so low that no additional efforts for risk reduction are justified (ibid). Tolerable risks relate to “activities seen as worth pursuing for their benefit” (Dow et al. 2013a) but where additional efforts to risk reduction are required to keep riskwithin reasonable levels. Dowet al. (2013a) describehow the scopeof risks that fallwithin this area is heavily influencedbyadaptationopportunities andconstrains and therefore the categorisation ofrisksvariesspatially,jurisdictionally,andtemporally.Constraintsmaylimittherange of available adaptation options creating the potential for residual damages for actors, species,orecosystems.Withinthetolerableriskspace, theriskofresidualdamagemay beviewedas anacceptableor tolerable trade-off under somecircumstances (deBruin etal.2009). Intolerable risksgobeyondsociallynegotiatednormsandvaluesalthough adaptation actionhasbeen taken (Dowet al. 2013a).At this stage, adaptationoptions thatarepracticaloraffordabletokeepvaluedsocialobjectivesorgoodswithinthenorm arenolongeravailable.Theserisksrepresent threats tocoresocialobjectivesregarding health,welfare, security, or sustainability (KlinkeandRenn2002;Dowetal. 2013a). Emerging literatureunderpinningChaps.16,17, and19of the IPCC5thAssess- mentreportpoint towardslimits intheabilityofsystemstoadapt toclimatestressors (Dowetal.2013a,b;Warneretal.2013;Adgeretal.2009).Adaptation limits—for example“softlimits”relatedtoinstitutionsandplanningprocesses,and“hardlimits” relating to physical characteristics of a system-constitute a point atwhich existing adaptationoptionscanno longerprotect theobjectivesandneedsofactors andsys- tems against intolerable risks (Adger et al. 2009; see alsoMechler and Schinko 2016; introduction byMechler et al. 2018 and chapter by Schinko et al. 2018 in this book).At the limit between tolerable and intolerable risk, the riskmust either beaccepted, theobjective itselfmustbeabandoned,oradaptationmustbe transfor- mative to avoid intolerable risk (Dowet al. 2013a). Figure13.1depicts acceptable, tolerableand intolerable risks, separatedby limitsofacceptable riskandadaptation limits. The turning space before an adaptation limit is reached, can be described as an adaptation frontier. Preston et al. (2014) define it as the “domain between a socio-ecological system’ssafeoperatingspaceand itsunsafeoperatingspace”.The adaptationfrontierisadomainwherefeasibleandaffordableadaptationactionisstill available andhas thepotential to secureobjectives andneedsof actors andsystems (ibid.)However, the frontier ischaracterisedbyuncertainty if theavailableoption is usedinanefficientandtimelymannerwhichisneededtostayawayfromadaptation limits (Dowetal. 2013a). According to Preston et al. (2014) and underpinning literature (Mechler and Schinko 2016; chapter by Schinko et al. 2018 in this book) adaptation can offer two typesofbenefits to systemson the frontier:On theonehand, reducing thevul- nerabilityof systems tomove themawayfromtheedgeof the frontier.On theother hand, enhancing resilience, enabling systems to persist despite the continuedpres-