Comparative assessment of human and sectoral impacts of the 2010 and 2022 floods in Khyber Pakhtunkhwa, Pakistan: evidence from Jaccard similarity index and Noy‐lifeyears framework

Floods occurring 12 years apart, in 2010 and 2022, accounted for 50% of the total monetary damage in Pakistan, yet comparative assessments continue to rely primarily on aggregate damage statistics that obscure persistent vulnerabilities and human-development impacts. This study conducts a dual comparative analysis of the multisectoral flood damages from the 2010 and 2022 events in Khyber Pakhtunkhwa province, Pakistan, to evaluate whether post-2010 disaster governance reforms translated into meaningful resilience gains. First, based on commonly affected severe districts, sectoral damage data for 2010 and 2022 for districts are harmonized to a common administrative geography and normalized to enable like-for-like comparison despite boundary changes and scale differences. Spatial-sectoral overlap in flood impacts was then quantified using the Jaccard Similarity Index, selected to identify persistent versus shifting vulnerability patterns across districts and sectors. Second, the Noy-lifeyears framework was applied to translate mortality, affected population, and economic damage into a human-centric measure of lifeyears lost. Jaccard analysis revealed limited degrees of similarity in the impacts of the two floods in 2010 and 2022 (mean Jaccard Index approximate to 0.30), suggesting that vulnerability has not simply repeated but redistributed across the province. Despite lower structural damage in several sectors in 2022, the Noy-lifeyears framework indicates that the 2022 floods resulted in greater human development losses than the 2010 floods, with total lifeyears lost approximately 4.6 percent higher. This reconciles the apparent paradox of the 2022 floods being structurally less severe yet socially more damaging. The findings demonstrate a critical resilience gap between infrastructure protection and human wellbeing. The study advances comparative disaster assessment beyond conventional loss accounting and provides evidence to support people-centered flood risk governance.