Toward integrated health projections under climate change: from compound hazards to vulnerability and adaptation

Climate change is fundamentally altering the landscape of global health through more frequent and intense extreme events, complex exposure pathways, and widening health inequalities. Therefore, future health projections require an integrated framework that goes beyond single hazards and average populations, incorporating compound disasters, vulnerable groups, and adaptive capacity.

First, climate-related health risks often arise from compound hazards, such as hot nights combined with urban heat, droughts interacting with heatwaves, and cascading events like wildfires. These interacting exposures can amplify health impacts beyond what is expected from each factor alone, highlighting the need for multi-hazard approaches in health projection models.

Second, health impacts of climate change are not evenly distributed. Vulnerable populations, including people with disabilities and socioeconomically disadvantaged groups, experience disproportionately higher risks and healthcare burdens during extreme temperatures. These double disparities in both health outcomes and socioeconomic status indicate that equity-sensitive projections are essential for realistic health risk assessment and policy planning.

Finally, adaptation is a key determinant of future health risks. Emerging evidence shows that strengthening healthcare systems, improving early warning systems, and implementing environmental and social interventions can substantially reduce climate-related health burdens. Integrating adaptation into climate-health projections is therefore essential to move from impact estimation toward actionable and policy-relevant scenarios.