Climate Change Adaptation: Operational Taxonomy and Metrics

The development of adaptation indicators and metrics that can be aggregated and compared to support environmental management is a key challenge for climate experts, finance institutions, and decision-makers. To provide an operational ex-ante evaluation of alternative adaptation strategies, statistical evaluation was conducted on 1562 adaptation projects contained in the Nationally Determined Contributions (NDCs) submitted by almost all parties who signed the Paris Agreement in 2015. As a preliminary stage, we are suggesting a physical risk taxonomy derived from climate model databases and an adaptation project taxonomy using a text analysis. The second stage, consisting of an evaluation metric using a correspondence analysis between adaptation projects and risk classes, was inspired by the analogy with adaptation mechanisms in living organisms-assessing the correct correspondence between threats from the environment and adaptive solutions. It allowed us to develop a coefficient ranging from 0 to 1, expressing the degree of correspondence between adaptive measures' categories and hazard levels, which we refer to as fitness. Our coefficient would make it possible to compare project classes with each other ex-ante or, conversely, to deduce the most relevant adaptation solutions from climate-change-related hazards. The fitness coefficient could also be used as a preliminary stage of assessment to create a short-list of adaptation projects that are relevant to address a given physical hazard with a given intensity.