Uneven hydroclimatic risk and land access constraints challenge refugee agricultural self-reliance in Uganda

Uganda's refugee policy is widely regarded for promoting agricultural self-reliance among the country’s nearly 2 million refugees, the largest refugee population in Africa. However, viability of this model is often challenged by how hydroclimatic shocks interact with household capacity to absorb them, an interaction that remain poorly understood. Here, we address a key gap by explicitly distinguishing unimodal and bimodal rainfall regimes and linking regime-specific drought and wetness dynamics to refugee livelihood exposure and household land access. We analyse 6-month Standardized Precipitation Evapotranspiration Index (1981-2024) and Vegetation Condition Index (2001-2024) anomalies, focusing on May-October main growing and harvest season. We find that the interannual extremes are highly episodic and often asynchronous between rainfall regimes. Only 2009, 2016, and 2023 exhibit widespread drought in both regimes, whereas only 2011 and 2012 are widely wet in both. Many large events are regime-specific, producing spatially uneven exposure, and long-term trends in affected area are weak relative to year-to-year variability. Major droughts are characterized by a late-season moisture deficit compounded by elevated atmospheric demand, with vegetation responses that are broadly consistent but spatially heterogeneous. We further show that hydroclimatic shocks intersect with rapidly rising refugee exposure in a small set of districts and with large structural constraints on land access and food-related outcomes. Notably, refugees typically hold one-eighth of the mean arable land as host households, a structural deficit suggesting that climate shocks rapidly and unevenly translate into production shortfalls rising market and aid dependence. These findings underscore the fragility of the self-reliance model under spatially uneven, episodic drought conditions. Sustaining refugee self-reliance will not only require spatially explicit climate monitoring but also need structural interventions in refugee-hosting regions where climatic, demographic, and land access pressures converge. • Uganda’s refugee-hosting districts span distinct unimodal and bimodal rainfall regimes. • Widespread drought in both regimes occurred only in 2009, 2016, and 2023. • Bimodal areas show more moderate droughts, while severe unimodal events last longer. • Refugees typically hold one-eighth as much arable land as host households. • Climate shocks can rapidly and unevenly translate into production shortfalls disproportionately affecting refugees.