A household‑level flood social vulnerability index in Malawi: exploring the intersection between farming and non‑farming households

Social factors moderate the impacts of natural hazards, which means that households are affected differently when exposed to the same hazard. This differential impact of hazards can be explained by the concept of social vulnerability, which is commonly assessed to inform flood preparedness and response measures. Most of these assessments, however, focus their analyses on large administrative units and neglect the heterogeneity of households within them, ultimately providing an oversimplified picture of risk. By leveraging a novel data source in Malawi’s national social registry, this paper proposes a comparative assessment of social vulnerability to floods at the household level in Malawi. While the method proposed can be applied to any district, provided data availability, Nsanje – one of the most disaster-prone districts in the country – is selected as a case study. Using Principal Component Analysis on rich census-scale data, the study is able to generate detailed household social vulnerability profiles that can inform decision-makers requiring a granular understanding of variations in vulnerability. In addition, where the social vulnerability literature often assumes that households engaged in agriculture simply are more vulnerable due to the climate-sensitivity of their livelihoods, this study goes further and seeks to explain the differential vulnerabilities of farmer households, which is particularly relevant when studying agrarian economies like Malawi. The results of the study reveal large spatial variations in household social vulnerability to floods in Nsanje, as well as differences in vulnerability patterns among farming and non-farming households. For both household types, poverty is identified as the main determinant of social vulnerability.