Integrated climate, health, and economic impacts of sustainable aviation fuel and hydrogen pathways

In recent years, the rapid growth of global aviation has intensified emissions, prompting the search for cleaner energy sources. This study compares Sustainable Aviation Fuel (SAF) and hydrogen across cost-benefit performance, climate impacts, and health effects at 1,134 global airports. Seven scenarios were designed: a BAU baseline and six pathways representing optimistic and pessimistic projections of SAF, hydrogen, and their hybrid use. By 2070, the optimistic mixed-use scenario (MIX-OPT) achieves the highest total economic returns (USD 12,331.23 billion) and health benefits (USD 12,973.84 billion), reduces the modeled aviation-related CO 2 concentration increment by 62.3% relative to BAU, and limits PM 2.5 -related premature deaths to approximately 400,000, whereas hydrogen-only pathways perform worst. Males and older populations remain more affected, and Chhatrapati Shivaji Maharaj International Airport (BOM) has the highest modeled premature-death count among the assessed airports under the study assumptions, which does not indicate the highest per-capita mortality risk. Positive early net benefits under SAF-OPT and higher long-term health benefits under MIX-OPT support considering early SAF deployment followed by an increasing hydrogen contribution, a conditional option under the prescribed assumptions rather than a universally optimal strategy.