Study Reveals European Populations More Resilient to Cold Weather than Heat

A recent study conducted by the Barcelona Institute for Global Health (ISGlobal) has highlighted that the population in Europe has shown a greater ability to adapt to colder temperatures compared to warmer ones over the past two decades. This research, which was a collaborative effort with the Barcelona Supercomputing Center (BSC) and published in The Lancet Planetary Health, indicates a notable decline in the risk of mortality associated with cold weather, while the reduction in heat-related deaths has been comparatively modest.

The researchers examined temperature and mortality data from over 800 regions across 35 European countries spanning the years 2003 to 2020. Their findings revealed that the relative risk of death due to extreme cold decreased by 2% annually. Conversely, the risk associated with high temperatures also diminished, but at a slower rate of 1% per year.

To improve the accuracy of their findings, the team developed a novel framework termed Extreme-Risk Temperature (ERT), which accounts for regional differences in vulnerability to temperature extremes. This approach enables a tailored assessment of temperature thresholds that elevate mortality risk for specific geographic areas. The analysis revealed that, during the 2003-2020 period, Europe experienced an annual decrease of 2.07 dangerously cold days, while dangerously hot days increased by 0.28 days per year.

Notably, the study found significant regional disparities in temperature-related mortality risks. For instance, Southeastern Europe, despite generally warmer weather, exhibited a higher incidence of both extreme heat and cold days, leading to an increased risk of mortality.

Researchers observed that European populations have improved their capacity to cope with cold weather--a phenomenon referred to as adaptation--more effectively than with extreme heat. There remains a pressing need for enhanced strategies to mitigate heat-related health risks, as evidenced by a 2024 survey indicating that only 20 out of 38 European nations have implemented temperature monitoring systems, while 17 countries lack comprehensive heat-health action plans.

Furthermore, the study examined the interplay between extreme temperatures and air pollution, noting that occurrences of 'compound days'--when extreme temperatures coincide with high pollution levels--were present on 60% of heat-ERT days and 65% of cold-ERT days. While the frequency of these compound days has generally decreased, there has been a concerning rise in dangerously hot days accompanied by elevated ozone pollution levels, which increased by 0.26 days annually.

As climate change intensifies, the increasing frequency of combined heat and ozone episodes poses a significant health threat in Europe. Researchers emphasize the necessity for targeted strategies to address the dual challenges of extreme temperatures and air pollution due to their compounded health effects. This study forms part of the EARLY-ADAPT project, which investigates how populations are adjusting to the public health challenges posed by climate change.