Climate change and population: an assessment of mortality due to health impacts
Résumé
We develop a model of population dynamics accounting for the impact of climate change on mortality through ve channels (heat, diarrhoeal disease, malaria, dengue, undernutrition). An age-dependent mortality, which depends on global temperature increase, is introduced and calibrated. We consider three climate scenarios (RCP 6.0, RCP 4.5 and RCP 2.6) and find that the five risks induce deaths in the range from 135,000 per annum (in the near term) to 280,000 per annum (at the end of the century) in the RCP 6.0 scenario. We examine the number of life-years lost due to the five selected risks and find figures ranging from 4 to 9 million annually. These numbers are too low to impact the aggregate dynamics but they have interesting evolution patterns. The number of life-years lost is constant (RCP 6.0) or decreases over time (RCP 4.5 and RCP 2.6). For the RCP 4.5 and RCP 2.6 scenarios, we find that the number of life-years lost is higher today than in 2100, due to improvements in generic mortality conditions, the bias of those improvements towards the young, and an ageing population. From that perspective, the present generation is found to bear the brunt of the considered climate change impacts.