How to Assess Nationally Determined Contributions? A systematic review and methodological proposal

The Paris Agreement relies upon peer pressure to induce states to first promise and then deliver climate action. The peer pressure is centered on nationally determined contributions (NDCs). Generating sufficient peer pressure is easier if it is possible to assess and compare NDCs. Here we review (1) the existing literature on methodologies for assessing NDCs, (2) evaluate the available datasets on NDCs that could be used for such assessments, and (3) propose a standardized methodology for NDC review. We find that there is a dearth of research on the assessment of NDCs, with only a few academic publications and a larger number of gray literature publications dealing directly with the topic. This lacuna is especially surprising considering the open access availability of large and detailed datasets on the NDCs, including NDC Explorer, Climate Action Tracker etc. Based on the assessment of existing methodologies, we propose our own multidimensional approach to assessing NDCs and to measuring changes in ambition over time.