How heat killed over 47,000 people in hottest year ever recorded

The figure is revealed in a modelling study, led by the Barcelona Institute for Global Health, published in the journal Nature Medicine on Monday. However, the international research group also reports that society appears to have adapted to the heat.

The team used mortality data from the European Statistical Office (Eurostat) on 96 million deaths to estimate the heat-related mortality burden in 2023 for 823 regions in 35 European countries.

According to these estimates, there were 47,690 heat-related deaths in Europe last year. This is the second-highest mortality rate since such calculations began in 2015, with the highest rate recorded in 2022. The researchers found that the countries with the highest heat-related mortality rates are in southern Europe.

Greece (393 deaths per million inhabitants), Bulgaria (229), Italy (209), and Spain (175) occupy the top four places in the estimate. In comparison, Germany’s rate was 76 deaths per million inhabitants in 2023.

In absolute figures, the research group estimates the number of heat-related deaths for 2023 at just under 12,750 in Italy and 6,376 in Germany. In almost all of the countries analysed significantly more women than men died from the effects of heat, with older people particularly susceptible.

The Barcelona team, led by Elisa Gallo, also modelled the effects of heat-related mortality without adaptation measures. These include, for example, improvements in healthcare, social protection and lifestyle, progress in occupational health, greater risk awareness, and more effective communication.

Without these measures, heat-related mortality in 2023 is likely to be 80% higher in the general population and over 100% higher in the 80+ age group.

“Our results show how there have been societal adaptation processes to high temperatures during the present century, which have dramatically reduced the heat-related vulnerability and mortality burden of recent summers, especially among the elderly,” said Gallo.

She said the minimum mortality temperature – the optimal temperature with the lowest mortality risk – has gradually increased on average across the continent since 2000, from 15 degrees Celsius in the period 2000 to 2004 to 17.7 degrees Celsius in the period 2015 to 2019.

“This indicates that we are less vulnerable to heat than we were at the beginning of the century, probably as a result of general socio-economic progress, improvements in individual behaviour and public health measures such as the heat prevention plans implemented after the record-breaking summer of 2003,” added Gallo.

Just recently, the same research group also presented “Forecaster.health,” an online early warning system that provides forecasts of cold and heat-related mortality risk by gender and age for 580 regions in 31 European countries.

The free tool provides forecasts up to 15 days in advance and is not only based on meteorological data but also incorporates epidemiological models.