Drought vulnerability and risk assessments: State of the art, persistent gaps, and research agenda

Reducing the social, environmental, and economic impacts of droughts and identifying pathways towards drought resilient societies remains a global priority. A common understanding of the drivers of drought risk and ways in which drought impacts materialize is crucial for improved assessments and for the identification and (spatial) planning of targeted drought risk reduction and adaptation options. Over the past two decades, the authors of this paper have witnessed an increase in drought risk assessments across spatial and temporal scales drawing on a multitude of conceptual foundations and methodological approaches. Recognizing the diversity of approaches in science and practice as well as the associated opportunities and challenges, this paper presents the outcomes of a systematic literature review of the state of the art of people-centered drought vulnerability and risk conceptualization and assessments, and identifies persisting gaps.

Of the reviewed assessments:

1. More than 60% do not explicitly specify the type of drought hazard that is addressed.
2. 42% do not provide a clear definition of drought risk.
3. 62% apply static, index-based approaches.
4. 57% of the indicator-based assessments do not specify their weighting methods.
5. Only 11% conduct any form of validation.
6. Only ten percent develop future scenarios of drought risk.
7. Only about 40% of the assessments establish a direct link to drought risk reduction or adaptation strategies, i.e. consider solutions.

This paper discusses the challenges associated with these findings for both assessment and identification of drought risk reduction measures and identifies research needs to inform future research and policy agendas in order to advance the understanding of drought risk and support pathways towards more drought resilient societies.