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

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.