Humans have become less susceptible to the effects of heat due to a combination of adaptations, particularly air conditioning. The availability of air conditioning is expected to continue to increase. Reduced exposure to cold days is a significant factor in the increased life expectancy experienced in the  over the past 30 years. This benefit from reduced exposure to cold can be further attributed to people migrating to warmer climates. Overall, there is strong evidence that populations can acclimatize to warmer climates via a range of behavioral, physiological, and technological adaptations. [T]he scientific evidence is clear that cold is a more potent hazard than heat.