Delineating resilient regional adaptation pathways

Deep uncertainty in the form of climate and socio-economic change is challenging key regional systems. Adaptation pathways (APs) offer an approach for sequencing interventions to enhance regional resilience. We present PATHS, a framework comprised of two tools that operationalizes AP delineation in diverse contexts by combining risk assessment with dynamic decision support. The Regional emerging Problem Inference Engine (REPIE) provides a risk evaluation based on hazard, exposure and vulnerability factors, using thresholds and weights to produce scenario-dependent risk curves. The Dynamic Contingency Response Tool (DCRT) identifies optimal APs for these scenarios through multi-criteria genetic optimization, evaluating interventions by effectiveness, cost, feasibility, and other characteristics. Applied to the case of socioeconomic drought in the water system of East Attica, Greece, PATHS produces balanced APs that combine interventions such as rainwater harvesting, reclaimed wastewater use, campaign policies, and sewer mining, demonstrating the usefulness of the approach in future proofing regional systems.