Vulnerability and capacity indication approaches attempt to say something about possible future impacts based on data collected on the current state of the exposure unit, often combined with social system variables representing capacity. Vulnerability and capacity indicationapproaches face the challenge that the aggregation of indicating variables into a vulnerability index can hardly be supported by theory nor can the results be validated empirically (Hinkel 2011a). Due to the lack of theory, some approaches seek to validate through data generated in interviews and focus groups against the "narratives" of vulnerability present in the literature (e.g. Mustafa et al. 2008). Other approaches use expert judgement, but different experts usually rank dimensions differently (Brooks and Adger 2005). Nonetheless, current work on developing and improving vulnerability indicators to address these issues is ongoing (see e.g. Regions 2020, ClimWatAdapt Project and ESPON project). The difference between impact attribution and vulnerability indication approaches is that the former require data on observed impacts while the latter are only applied in the absence of such data.