With increased access, sustainable cooling can prevent up to 80% of heat-related deaths

Heatwaves represent an acute health hazard, especially for vulnerable age groups (<1 year and >65 years).  According to the 2024 “Lancet Countdown on health and climate change”, in 2023, people were exposed, on average, to an unprecedented 50 more days of health-threatening heat than expected without climate change ^[1]. This resulted in 167% more annual deaths of adults older than 65 years than in the 1990s.

Over 47,000 people died in Europe because of high temperatures in 2023, according to a study published in Nature Medicine ^[2]. Nevertheless, the researchers report that without adaptation processes, the burden of heat related mortality over the past year would have been 80% higher.

 

Findings from the 2024 “Lancet Countdown on health and climate change” confirm that adaptation processes such as air conditioning contribute to alleviate heat related mortality.

Taking into account access to air conditioning, the authors of the Lancet Countdown calculated that the ratio of potential heat-related deaths prevented by air conditioning to actual heat-related deaths among those older than 65 years was 74% for high Human Development Index (HDI) countries, and 76% for very high HDI countries ^[2].

 

Unfortunately, significant inequities exist in global access to air conditioning and the resultant benefits. In 2021, the proportion of households with air conditioning reached 43.8% in high HDI countries and 48.4% in very high HDI countries, compared with just 4.7% and 14.3% in low and medium HDI countries, respectively ^[1]. Consequently, the ratio of potential heat-related deaths prevented by air conditioning to actual heat-related deaths among those older than 65 years was 4% for low Human Development Index (HDI) countries, 12% for medium HDI countries. Furthermore, the number of health-threatening heat days added by climate change decreases with increasing HDI level.

 

These data reflect the urgency of implementing equitable, affordable, and sustainable health-protecting cooling solutions to save lives.

 

 

Sources

[1] Romanello, Marina et al. The 2024 report of the Lancet Countdown on health and climate change: facing record-breaking threats from delayed action. The Lancet, Volume 404, Issue 10465, 1847 – 1896. https://www.thelancet.com/countdown-health-climate

 [2] Gallo, E., Quijal-Zamorano, M., Méndez Turrubiates, R.F. et al. Heat-related mortality in Europe during 2023 and the role of adaptation in protecting health. Nat Med (2024). https://doi.org/10.1038/s41591-024-03186-1