Societal well-being outcomes are a key element of climate security analyses but are subject to multiple uncertainties affecting the complex human-Earth system. In this study, we generate a large ensemble of scenarios using the Global Change Analysis Model (GCAM) to explore the determinants of uncertainties in joint outcomes for food, water, and energy security. GCAM is an integrated, multi-sector model that considers interactions across various sectors, and represents demand for food and residential energy across multiple sub-populations defined by income level. We sample from a wide range of future uncertainties in both physical and societal factors, including climate system outcomes, emissions reduction policies, socio-economic drivers, and food-energy-water supply/demand. We evaluate each scenario by computing global and regional well-being outcomes and perform scenario discovery to identify the key drivers and uncertainties associated with the outcomes of interest. Ultimately, we anticipate that our findings will help identify scenarios that can facilitate research on societal well-being outcomes, especially in multi-sector contexts.