A Longitudinal Municipal Vulnerability Index for Annual Climate Tracking in Municipalities of Varying Sizes

Many composite vulnerability indices are developed at regional or national scales and are updated infrequently, limiting their usefulness for annual climate vulnerability assessment at the municipal level. We developed the Municipal Vulnerability Index (MUVI), a 21-indicator composite framework combining municipal administrative statistics, remotely sensed green-area data and station-observed meteorological records. MUVI was applied to 13 municipalities in Győr–Moson–Sopron County, Hungary, for 2011–2024. Each indicator is normalised to its municipality-specific 2011–2024 mean, so annual values are interpreted relative to the municipality’s own study-period conditions rather than a common cross-sectional benchmark. For diagnostic purposes, the indicators are grouped according to the IPCC AR5 vulnerability dimensions of exposure, sensitivity and adaptive capacity, and their contributions are examined using polarity-corrected component profiles. All 13 municipalities recorded their highest MUVI value in 2024. Heatwave-day ratios were also elevated in that year, while demographic and infrastructure indicators contributed differently among municipalities. In the sensitivity analysis, the 2024 municipality score ordering was largely preserved under PCA-derived alternative weights (τ = 0.949) and Monte Carlo weight perturbations (mean τ = 0.946). Leave-one-out analysis identified greater sensitivity to economic and socioeconomic indicators. MUVI provides an annually updatable screening framework for monitoring municipal vulnerability indicators and identifying areas that require more detailed local assessment, where suitable longitudinal administrative and meteorological data are available.