More than 61,000 people died as a result of the extreme heat waves that swept across Europe last year, according to what was reported A study published on Monday In the journal Nature Medicine.
The findings suggest that two decades of efforts in Europe to adapt to a hotter world have failed to keep pace with the pace of global warming.
“In an ideal society, no one should die of heat,” said Joanne Pallister, research professor at the Barcelona Institute for Global Health and lead author of the study.
This summer is likely to be even worse: On top of climate change, Earth entered a normal El Niño weather pattern during the summer for the first time in four years, creating conditions that will warm many parts of the world. The season has already started breaking various global temperature records.
Researchers who studied last year’s heatwaves used data collected by the European Union from 35 countries, including some non-member states.
Most of the dead were women, especially those over 80 years of age. Among young men, men died at higher rates. The Mediterranean countries, where the temperatures were hotter at the time, suffered the most: Italy, Spain and Portugal had the highest rates of heat-related deaths.
Dr. Pallister said extreme temperatures were expected that summer based on how much the planet has warmed overall in the past decade. When temperatures rose, many European governments had “heat action plans” ready, developed in response to an unexpected and more deadly heat wave in 2003, but these modifications were not enough to prevent mass casualties, he said.
Dr Pallister added that as the climate continues to change, the world can expect more and more deaths from extreme heat.
The European Union’s statistics office, Eurostat, regularly publishes the number of excess deaths (deaths above the expected average for a given time period) in European countries. Dr. Ballester and his colleagues took the official reports on total excess deaths from June through August 2022 and estimated how many deaths could be attributed to heat rather than other unusual factors such as the coronavirus.
They used epidemiological models, which means they matched recent historical temperature trends in different regions of Europe with mortality trends over the same period, to establish numerical relationships between mortality and temperature fluctuations in those regions.
“When there is a rise and a fall in temperature, we always see a rise and a fall in mortality,” said Dr. Pallister.
His team’s findings mirror those of a study conducted shortly after the 2003 European heat wave, with some of the same collaborators. Previous research found more than 70,000 excess deaths in Europe during the summer of 2003.
The previous study did not separate heat-related deaths from other excess deaths, so Dr. Ballester cautioned that the two numbers cannot be directly compared. The 2003 study also covered just 16 European countries, while the new study covered more than twice that number. When the researchers narrowed the results of this new modeling to those same 16 countries, they ended up with more than 51,000 heat-related deaths.
The researchers are applying the same epidemiological models to the 2003 heat wave to compare the two years more precisely. Excluding drastically different numbers after a similar analysis, their results indicate that public policies adopted after 2003 have only slightly helped reduce the toll of extreme heat.
In France, the additional deaths exceeding 10,000 in the summer of 2003 had political consequences, including the resignation of the country’s director general of health. Over the past 20 years, officials there and elsewhere in Europe have invested in early warning systems for extreme heat, public cooling centres, volunteer forces to check on elderly residents, and better coordination between social services and hospitals.
But the changes across Europe were not enough. “It’s a spectrum,” said Dr. Pallister, across different regions and populations.
The elderly remain at high risk, especially those without access to air conditioning, as well as people who work outdoors. Older women were likely the worst-off group last summer simply because they live longer than men at ages when people are most vulnerable and most likely to die during extreme heat, Dr. Pallister said. Other researchers, he said, have studied the causes of demographic differences in death rates: For example, men tend to have worse health outcomes at younger ages, and some outdoor occupations, such as construction, are male-dominated.
This paper did not compare deaths among people of different races or ethnicities, but that this is another important factor in heat exposure, said Juan Declett Barreto, a senior sociologist at the Union of Concerned Scientists who studies the health effects of environmental hazards. He did not participate in this study. While Dr. Declett Pareto is less familiar with the demographics of Europe, he did say that people who work outdoors and are more exposed to the heat in the United States tend to be immigrants of color.
A spokesperson for the agency wrote via email that Eurostat does not have a breakdown of excess mortality data by race, ethnicity, or immigration status. In their paper, Dr Ballester and colleagues recommend that countries reporting to Eurostat better coordinate how health data is collected and shared, including more demographic breakdowns. This year, the European Parliament proposed a regulation to do so.
Even without additional demographic information, Dr. Declett Pareto said the study was “very timely” given the sweltering heat of this summer. He thought the study’s methods appeared sound, given that “there is a fairly well-known public health relationship between overheating and excess mortality.” He also agreed that a comparison of the heatwaves in 2022 and 2003 was useful in revealing which health and policy interventions are still needed.
Four years ago, the International Federation of Red Cross and Red Crescent Societies published guidance to help city officials respond to heat waves, and its recommendations included changes to homes and physical infrastructure, such as improving energy efficiency and ventilation.
Dr. Declett Pareto said other public health researchers have found that the most important factor in preventing deaths during heat waves is expanding access to air conditioning.