Global spillover risks from humid-heat-induced production disruptions

Humid heat can reduce local labour productivity, dampening production in most economic sectors. These regional production disruptions may propagate through global supply chains, which result in spillover effects and induce macroeconomic losses. In a warming climate, characterised by an increasing frequency and intensity of heatwaves, these spillover risks to global producers and consumers due to humid-heat-induced production disruptions remain unclear. By integrating a recently released wet-bulb globe temperature dataset into the well-established agent-based economic loss-propagation model Acclimate, we assess direct regional production losses as well as resulting indirect losses and risks to different regional sectors within global supply chains under present-day climate and future warming scenarios. We identify key producers and consumers that are particularly prone to supply chain disruptions and highlight the heterogeneity of risks across different income groups within and between countries. These results can support the design of region-specific risk management strategies for humid heat and guide the prioritisation of adaptation investments toward the most vulnerable sectors and regions.