Aerosol exposure versus aerosol cooling of climate: what is the total health outcome?

Abstract Particles, climate change, and health have thought-provoking interactions. Emissionof aerosol particles is one of the largest environmental problems concerning humanhealth. On the other hand, aerosol particles can have a cooling effect on climate and 5 a reduction of those emissions may result in an increased temperature, which in turnmay have negative health effects. The objective of this work was to investigate the“total health” effects of aerosol emissions, which include both exposure to particlesand consequences of climate change initiated by particles. As a case study the “totalhealth” effect from ship emissions were estimated by adding the number of deaths from 10 aerosol emission exposure to the calculated number of lives saved from the cooling ef-fect of the particles. The analysis indicated an annual mortality from ship emissionsof 26000 (minimum uncertainty range −5000 to 52000), with 60000 deaths from di-rect aerosol exposure and 34000 lives saved by the cooling effect of particles. This isthe first attempt to calculate the combined effect of particle emissions on health. We