Indicators and metrics to evaluate urban adaptation: a systematic review

Assessing the effectiveness of climate adaptation action is the focus of intense debates across scientific and policy arenas. Measurement is essential for effective adaptation management and operation, and indicators and metrics (I&M) are claimed to have a pivotal role. Surprisingly, there are, however, no systematic efforts so far to understand the progress of science in the provisioning of I&M. To shed light on these timely discussions, we here analyse 137 scientific publications and 901 I&M (including indices) proposed in the literature to measure adaptation to climate change with a particular focus on urban areas. The challenges we have faced speak about a field that is complex to track and understand as a result of a lack of common terminology, standardisation and reference guidelines. This complexity has originated diverse, context-specific and sometimes competing approaches to developing I&M. Based on our evidence, we raise the critique that current I&M proposals are highly technical, not sufficiently grounded on real needs and have little potential to support effective urban climate change adaptation. Our concern is now how to advance the adaptation evaluation research, policy and practice field in this messy space.