Climate change likely to cause a significant rise in heat-related deaths across Europe

By Dr. Sanchari Sinha Dutta, Ph.D.Reviewed by Benedette Cuffari, M.Sc.Jan 28 2025

Climate action could prevent 70% of 2.3 million projected heat-related deaths in European cities by 2099

In a recent study published in Nature Medicine, researchers predict that climate change will likely cause a sharp rise in heat-related mortality throughout Europe by the end of this century.

How climate change impacts mortality

Heat and cold stress are major health risk factors associated with significant mortality across Europe, particularly among individuals with pre-existing health conditions like cardiovascular disease, diabetes, and obesity. Existing evidence indicates that cold-related mortality in Europe is about 10 times greater than heat-related mortality.

Recent studies have reported that temperature-related mortality in Europe may decline with climate change. However, growing populations and urbanization amplify exposure to high temperatures, which subsequently increases the risk of heat-related mortality.

The balance between increased heat-related mortality and reduced cold-related mortality is a major determinant of the net effect of climate change, which several factors, including geographical locations, population-level adaptive capacity, demographic characteristics, and socioeconomic status, can influence. In the current study, researchers provide a comprehensive assessment of the net effect of climate change on temperature-related mortality across 854 European cities under various climate, demographic, and adaptation scenarios.

Important observations

The current study estimates that, without adaptation to heat, climate change can lead to over 2.3 million additional temperature-related deaths in 854 European cities by 2099 if strong policies are not implemented to reduce carbon emissions. However, 70% of these deaths could be prevented by rapid implementation of mitigation measures.

Three Shared Socioeconomic Pathway (SSP) conditions including SSP1-2.6, SSP2-4.5, and SSP3-7.0 were included in the analysis to make these projections. SSP1-2.6 corresponds to a sustainable world in which global warming barely exceeds 1.5 °C at its peak, whereas SSP2-4.5 corresponds to a world condition in which global warming remains below 3 °C. SSP3-7.0 corresponds to a world condition in which low priority is given to sustainability and environmental concerns, thereby leading to global warming near or above 4 °C.

The net death burden due to climate change in Europe may increase by 50% between 2015 and 2099 under SSP3-7.0, the lowest mitigation and adaptation conditions. This death burden can be reduced by at least two-thirds under the more stringent SSP1-2.6 and SSP2-4.5 conditions, in which high priority is given to reduce carbon emission.

In the absence of strong mitigation strategies, the estimated increase in temperature-related mortality can only be prevented through significant adaptation to heat, especially in the most vulnerable areas such as the Mediterranean region, Central Europe, and the Balkans.

Our results stress the urgent need to aggressively pursue both climate change mitigation and adaptation to increased heat. This is especially critical in the Mediterranean area where, if nothing is done, consequences could be dire. But, by following a more sustainable pathway, we could avoid millions of deaths before the end of the century.”

Ten European cities are projected to experience the highest temperature-related deaths by 2099. These cities include Barcelona, Madrid, and Valencia in Spain, Rome, Naples, Genoa, and Milan in Italy, Athens, Greece, Marseille, France, and Bucharest, Romania.

Due to their larger populations, the highest number of temperature-related deaths will likely occur in densely populated Mediterranean cities. However, several smaller cities in Malta, Spain, and Italy are also predicted to experience a high burden of temperature-related deaths.    

The impact of climate change on mortality was predicted to be less severe in cities away from the Mediterranean region. Other European capitals, such as Paris, were projected to see a smaller but significant increase in cumulative cold and heat deaths.

Comparatively, a net reduction in temperature-related deaths is probable in most cities in the British Isles and Scandinavian countries. However, this reduction would be outweighed by the 2.3 million additional deaths projected throughout Europe.

These results debunk proposed theories of ‘beneficial’ effects of climate change, often proposed in opposition to vital mitigation policies that should be implemented as soon as possible.”

Study significance

The current study provides concerning projections of temperature-related death rates that may affect multiple European cities in the absence of robust mitigation policies and appropriate heat adaptation strategies. Regional differences in temperature-related death tolls were also reported, which suggests a slight net decrease in death rates in Northern European countries but high vulnerability in the Mediterranean region and Eastern Europe areas.

Importantly, daily mean temperatures were used to make these projections, and as a result, they did not consider specific weather events, such as extreme nighttime temperatures and humidity conditions, which may modify the estimated death tolls.