Climatic change and household-level demographic dynamics: concepts and empirical evidence from sub-Saharan Africa

Climatic variability has been linked to multiple demographic and health outcomes, which have important implications for human welfare and development. Despite the importance of these outcomes, few studies have examined its impact on household size. Household size is an important correlate of wellbeing and is driven by multiple demographic processes that may be affected by environmental shocks. This paper describes these links conceptually, and then empirically examines how exposure to climate anomalies affects household size and three underlying components-fertility, marriage, and family agglomeration-that are observed in our data. We examine these relationships by linking harmonized census microdata from eleven sub-Saharan African countries with high-resolution climate data from the Climatic Research Unit (CRU) and modeling the effects of recent temperature and precipitation exposures on the outcomes of interest. Our analyses indicate that high temperatures may be associated with increases in household size. Models of the underlying demographic components of household size suggest that these temperature effects may be driven by increases in fertility and men's marriage, assuming the latter involves marriage into an existing household. Evidence from exploratory country-specific models reveals significant spatial heterogeneity, raising important questions about the contextual moderators of climate-family dynamics for future research.