It has been suggested that winter mortality rates, which appear to be more related to infectious diseases than to extremely cold temperatures, will be little impacted by climate change. Acclimatization of populations, however, may reduce the predicted heat-related morbidity and mortality. Kalkstein et al. People in Ottawa, on the other hand, showed no signs of potential acclimatization. It is important to note that acclimatization to increasing temperatures occurs gradually, particularly among the elderly, and may be slower than the rate of ambient temperature change.
Figures assume no change in population size and age distribution in the future.
Modified from Kalkstein et al. Air conditioning and adequate warning systems also may reduce heat-related morbidity and mortality in a warmer North America.