Germany is groaning under a heat wave. Sunday was the hottest day of the year so far. In some regions of Germany more than 35 degrees Celsius were measured, in Neckarwestheim even 37.2 degrees. At these temperatures, small children, pregnant women and especially older people quickly reach their stress limit if their bodies can no longer cool down sufficiently. A study in the journal Nature Medicine now shows how dangerous the increasingly hot summers are now: According to this, last summer claimed 61,672 heat-related deaths in Europe. And thus almost as much as in the exceptional year 2003.
That summer 20 years ago, more than 70,000 Europeans died as a result of the heat. In Paris alone there were hundreds, which is why the city had to convert a former wholesale market into a morgue.
“We did not expect such an increase.”
However, the summer of 2003 was an exceptional summer, it was more than two degrees warmer than the trend of the previous summers would have led one to expect. The governments drew conclusions from this and focused on heat prevention – from better communication of the health risks to the installation of cooling retreat rooms in public buildings, drinking water dispensers and the greening of cities. “Cities have done a lot,” says medical scientist Josep Maria Antó of the Barcelona Institute for Global Health, one of the authors of the Nature Medicine study. “But that wasn’t enough.”
In the summer of 2022, a similar number of people in Europe died again as a result of the heat, despite adaptation. “We didn’t expect such an increase,” says Antó. “With climate change we are entering uncharted territory.”
Europe is particularly affected by global warming, with temperatures rising by around one degree Celsius compared to the global average. And the summer of 2022 was the hottest in Europe on record. However, in contrast to the summer of 2003, it came anything but out of the blue. The authors write that the temperatures were not “extraordinary”. In other words, based on the development of the previous summers, one could have expected them. And yet more than 60,000 people in 35 European countries died as a result of the heat. 8173 in Germany alone.
The authors calculated this statistically by comparing the expected weekly temperatures and mortality rates based on the past 20 years with the actual temperatures and mortality rates. They were also able to solve the mystery of excess mortality, which had been determined last year. There were particularly high death rates in Germany in July. It is now clear that the heat was the decisive factor. According to the Nature Medicine study, nearly two-thirds of heat-related deaths in the summer of 2022 can be traced back to just one particularly hot week – July 18-24.
Most heat-related deaths overall were in Italy, Spain and Germany, which is mainly due to the fact that a particularly large number of people live there. On the other hand, the highest heat-related mortality rate was recorded in Italy, Greece and Portugal – Germany only appears in 13th place here. The authors also consider the countries of the Mediterranean region to be particularly at risk.
Within the population of individual countries, on the other hand, women are more at risk than men: According to the study, 63 percent more heat-related deaths occurred in women than in men, although there were large differences in the age groups: Men had higher heat-related death rates up to the age of 79 , but women higher from the age of 80 years – the age group with the vast majority of heat-related deaths. “Unfortunately, we don’t have any good explanations for these differences,” admits Antó. He assumes a combination of physiological and sociocultural reasons. However, data was not available for all countries – for Germany, for example, there was no breakdown for women and men.
In any case, from the point of view of Antó and his colleagues, the prevention plans have proven to be “insufficient” to “prevent the high level of heat-related mortality”. The doctor recommends tightening up and generalizing the measures taken so far: During heat waves, for example, older people should be reminded daily by their family doctor’s office to drink enough and protect themselves from the sun. “We need more intensive communication,” demands Antó. “Cool retreats are useless if people don’t feel like they could die from the heat.”
According to forecasts, this summer will again be very hot in Europe, possibly hotter than last year. “We are now realizing that these heat waves are our new normal,” says Antó. In order to get a sense of what could still be in store for us in future summers, he extrapolated the linear development of temperatures and mortality. According to this, an average of 68,116 heat-related deaths can be expected in Europe from 2030, 94,363 from 2040 and 120,610 from 2050 – if there is no adjustment.