Opportunity for health and wellbeing co-benefits of climate adaptation policies and programs: a Delphi study in the Australian Capital Territory

The integration of health and wellbeing co-benefits into climate policy and decision-making is limited. This study aimed to identify health and wellbeing co-benefits of climate change adaptation and mitigation, assess the perceived relevance and importance of co-benefits to policy and programme evaluation, and assess data availability to measure co-benefits. The relevance, importance, and data availability of 24 co-benefits of climate policies and programmes identified from a prior scoping review were surveyed using Delphi methodology by experts across diverse policy areas using the Australian Capital Territory (ACT) as a case study. We created an opportunity score that represented the combined relevance and importance for each co-benefit. Experts also identified additional co-benefits and provided qualitative responses, with agreement with the first round results assessed in the second round. We found that co-benefits that were rated as highly relevant were generally rated as highly important. The top five co-benefits based on opportunity score (relevance × importance) included: reduced mental health burden; increased comfort in the home; improved disaster preparedness; improvement in physical health; and economic benefits from averted healthcare costs. A high degree of consensus was achieved for all five top co-benefits, as well as those considered not relevant or important, indicating agreement on highest and lowest priority co-benefits across a range of climate change interventions and government directorates. While most co-benefits with high opportunity scores had available data, the availability of quality data was a key concern, with over half the identified co-benefits having no available data or uncertain data availability. Future research needs to develop a standardised methodology to measure co-benefits that incorporates indicators considered most relevant and important by experts, with the prioritisation of co-benefits in this Delphi study providing a guide for research and evaluation in other contexts beyond the ACT.