A Hybrid Process to Address Uncertainty and Changing Climate Risk in Coastal Areas Using Dynamic Adaptive Pathways Planning, Multi-Criteria Decision Analysis & Real Options Analysis: A New Zealand Application

Abstract

Decision makers face challenges in coastal areas about how to address the effects of ongoing and uncertain sea-level rise. Dynamic adaptive pathways planning (DAPP) and Real Options Analysis (ROA) can support decision makers to address irreducible uncertainties in coastal areas. This paper sets out what we learned by complementing multi-criteria decision analysis with DAPP and ROA when developing a 100-year coastal adaptation strategy in Hawke’s Bay, New Zealand. Lessons include the value of collaborative community and decision maker processes for increasing understanding about the changing risk over time, and the need to take early actions that enable a shift in pathway before those actions become ineffective. Modifications to the methods highlighted the importance of using several plausible scenarios for stress-testing options; considering costs and consent-ability early, to avoid the perception that hard protection will last; which criteria are appropriate for communities to assess; and making many pathways visible for future decision makers. We learned about the difficulties shifting thinking from short-term protection actions to longer-term anticipatory strategies. We found that a pathways system will require ongoing political leadership and governance with monitoring systems that can manage the adaptive process over long timeframes, by governments and their constituent communities.

Community-led initiatives for climate adaptation and mitigation

“…These tools often focus on communicating and better managing the risks associated with climate change on privately owned land and public/council owned land. 1 Some councils have gone as far as initiating managed retreat (see Radio New Zealand 2018), others have adjusted district plan designations, 2 while others have started dynamic adaptive pathways planning (see for instance Hawkes Bay Regional Council 2016; Lawrence et al 2019). Most of the emphasis to date has therefore been on improving the planning policies and rules for adaptation, rather than mitigation.…”

Economic Evaluation of Adaptation Pathways for an Urban Drainage System Experiencing Deep Uncertainty

“…The presented analysis undertook a cost-benefit analysis on a set of Adaptation Pathways generated by Babovic and Mijc [10] for an urban drainage system. The presented work builds upon the literature of assessing flood defence Adaptation Pathways by using a physically based assessment of flood damages in addition to exploring a range of ecosystem services and a wider range of flood defense solutions across a range of futures [11,12]. To achieve this, the Discounted Cash Flow (DCF) methodology was modified to be applicable to Adaptation Pathways.…”

National-Scale Built-Environment Exposure to 100-Year Extreme Sea Levels and Sea-Level Rise

“…In these situations, applying management interventions too early or too late can be managed using a dynamic adaptive policy pathways (DAPP) approach, where coastal flood exposure or impact indicators trigger adaptive actions ahead of adaptation thresholds [6,7,44]. Identification of coastal flooding adaptation thresholds and triggers over decades and centuries in response to SLR, requires detailed information on the location and timing of flooding and socio-economic impacts for present and future environments [44][45][46][47]. Applying 0.1 m SLR increments in coastal flood exposure assessments using high-resolution topographic data identifies the spatial variability of present built-asset exposure on temporal scales representing decadal change in SLR and thus included within a DAPP pathway.…”