Climate Vulnerability Index

A climate vulnerability index is a composite indicator that combines measures of exposure to climate hazards, sensitivity to those hazards, and adaptive capacity into a single comparable score for places or populations. The conceptual backbone is the IPCC framing, articulated clearly by Smit and Wandel, in which vulnerability rises with exposure and sensitivity and falls with the capacity to adapt. The measurement machinery owes much to Susan Cutter's Social Vulnerability Index, which showed how to select, normalize, and statistically reduce many socioeconomic variables into a defensible index of who is most at risk. A climate vulnerability index merges these traditions: it assembles biophysical exposure indicators with social sensitivity and adaptive-capacity indicators, puts them on a common scale, and aggregates them. The output ranks counties, communities, or households so that scarce adaptation resources can be targeted. Because it is a composite, every step, indicator choice, normalization, weighting, embeds judgments that must be made transparent.