Quantifying heat-related mortality attributable to human-induced climate change

Abstract The impacts of anthropogenic climate change remain largely unquantified. Here we detail and address limitations in existing methods for attributing health impacts to climate change, including the representation of the climate-health relationship, choices in calculating counterfactual temperatures, assessment of long-term trends and individual events, and estimation of the effects of adaptation. Applying these methods, we found over 1,700 deaths attributable to anthropogenic temperature increases in the Canton of Zürich (Switzerland) over 50 years. Changing exposures and vulnerabilities to heat, including due to adaptation, avoided over 700 deaths. Heat-related deaths peak during heatwaves but also occur throughout summer months and the fraction of deaths attributable to climate change is higher outside heatwaves. Our approach supports targeted adaptation measures, and the analyses described here could be adapted and applied elsewhere to assess the effect of climate change on other health impacts or economic losses. Teaser Synthesis of climatological and epidemiology methods finds 1,700 heat deaths attributable to climate change in the Canton of Zürich (1969-2018).