A systematic review of indicator-based drought vulnerability assessments (IBDVA): implications for sustainability in exposure, sensitivity, and adaptive capacity

Drought vulnerability assessments (DVA) have become paramount in addressing the multifaceted challenges posed by climate variability, particularly in regions heavily reliant on agriculture. This systematic review (1990–2023) synthesizes peer‑reviewed indicator‑based drought vulnerability assessments (IBDVA) that apply the IPCC three‑dimensional framework (exposure, sensitivity, adaptive capacity). Following PRISMA, 27 studies were included and 190 distinct indicators extracted and classified. Results show a marked increase in IBDVA publications after 2019, with most studies focused in Asia and Africa and at household to subnational scales. Exposure indicators (e.g., rainfall and temperature trends) show the greatest consensus, while sensitivity and adaptive‑capacity indicators are more heterogeneous and often overlap. Common analytical practices include PCA and equal weighting for indicator reduction or weighting, diverse normalization methods, and increasing use of GIS and machine‑learning (ML) for spatial prediction. We present a frequency‑based prioritized shortlist of practical, data‑feasible indicators for each dimension to improve comparability and application in data‑limited contexts. We recommend transparent indicator selection, scale‑specific standardization of indicator sets, and wider adoption of GIS/ML approaches combined with scenario‑based socio‑economic projections to enhance policy relevance and predictive capacity of future DVAs.