Abstract
Climate variability poses significant risks to Ethiopia's rainfall-dependent smallholder farming systems. Since meteorological patterns can vary widely across agro-ecological zones, understanding differences in vulnerability across these zones is essential for targeted adaptation. However, many existing vulnerability studies rely on basin-, zonal-, or inter-district analyses and apply composite indices without robustness testing, which can obscure within-district heterogeneity and limit policy relevance at the scale where adaptation decisions are implemented. This study assesses smallholder farmers' vulnerability to climate variability across three agro-ecological zones (midland, highland, and cold highland) in Legambo District, north-central Ethiopia. It examines spatial differences in vulnerability levels, identifies key biophysical and socio-economic drivers, and generates evidence to inform locally differentiated adaptation and development interventions. A mixed-methods approach was employed, combining household survey data from 347 randomly selected households with focus group discussions, key informant interviews, and long-term climate data. Forty-eight indicators were grouped into twelve major components and analyses using the Livelihood Vulnerability Index (LVI) and the LVI–IPCC framework, which conceptualise vulnerability in terms of exposure, sensitivity, and adaptive capacity. The robustness of the composite indices was assessed using a PCA-based sensitivity analysis, and household-level vulnerability distributions were examined to capture within-zone heterogeneity. The results reveal modest but consistent differences in vulnerability across agro-ecological zones. The cold highland zone was the most vulnerable (LVI = 0.370), driven by high exposure to climatic hazards, limited infrastructure, weak social networks, low innovation uptake, and constrained adaptive capacity. The highland zone exhibited moderate vulnerability, largely associated with inadequate water and health services and limited soil and water conservation practices. In contrast, the midland zone was the least vulnerable (LVI = 0.285), benefiting from greater livelihood diversification, better access to assets, and stronger adaptive capacity. The LVI-IPCC analysis confirmed these patterns, indicating higher exposure and sensitivity in the cold highlands and comparatively stronger adaptive capacity in the midlands. These findings indicate the interest of differentiated policy responses to strengthen resilience among smallholder farmers. In particular, the results indicate that improved rural roads, water supply, and health services, together with agro-ecological-zone-specific extension support and improved access to climate-resilient inputs, should strengthen adaptation planning and rural development program.