Navigating global health futures under the Shared Socioeconomic Pathways.

The Shared Socioeconomic Pathways (SSPs) provide valuable insights to understand how future socioeconomic changes could alter the magnitude and pattern of climate-related risks across sectors, which might facilitate or hinder adaptation and mitigation responses. Many sectors have created SSP narrative extensions to specify insights for their domains. In this Viewpoint, we created health narrative extensions for the SSPs, considering socioeconomic and demographic drivers and population health and health-system drivers. The projected health-relevant trajectories diverge substantially over the course of the 21st century. The SSP3 and SSP4 narratives detail changes that could contribute considerable risks to health, whereas the SSP1 and SSP5 narratives highlight the role of effective governance and adequate resourcing in reducing climate-sensitive population health outcomes and health-system drivers. Given that climate forcing is considered exogenous to these narrative extensions, SSP5's favourable health driver paths do not account for the potential adverse impacts of this high-emissions pathway. The narratives elaborate population health drivers that can improve the policy relevance of population health and health-system risk projections associated with climate change across a range of possible pathways, and link these drivers with relevant cross-sectoral issues (eg, water and energy). Further research is required to quantify key drivers of population health and health-system risks at global to local scales.