Received: 26 Jan 2021 – Accepted for review: 27 Jan 2021 – Discussion started: 29 Jan 2021
Abstract. This paper provides a state-of-art account on flood vulnerability indices, highlighting worldwide trends and future research directions. A total of 95 peer-reviewed articles published between 2002–2019 were systematically analyzed. An exponential rise in research effort is demonstrated, with 80 % of the articles being published since 2015. The majority of these studies (62.1 %) focused on the neighborhood followed by the city scale (14.7 %). Min-max normalization (30.5 %), equal weighting (24.2 %), and linear aggregation (80.0 %) were the most common methods. With regard to the indicators used, a focus was given to socio-economic aspects (e.g. population density, illiteracy rate, gender), whilst components associated with the citizen's coping and adaptive capacity were slightly covered. Gaps in current research include a lack of sensitivity and uncertainty analyzes (present in only 9.5 % and 3.2 % of papers, respectively); inadequate or inexistent validation of the results (present in 13.7 % of the studies); lack of transparency regarding the rationale for weighting and indicator selection; and use of static approaches, disregarding temporal dynamics. We discuss the challenges associated with these findings for the assessment of flood vulnerability and provide a research agenda for attending to these gaps.