July 2023 made history as the hottest month ever recorded on Earth, scientists confirmed last week. As wildfires blackened the air across swathes of the northern hemisphere, from southern Europe to Canada, a study examining the devastating human impact of extreme heat was published in the journal Nature. But while its principal finding that a 2022 heatwave in Europe killed 61,000 people made headlines around the world, another striking statistic got far less attention: 56% more women died than men.
The study found that older women are particularly vulnerable to the heat waves becoming more frequent and more intense across the world. It forms part of a growing body of evidence at the heart of a legal bid by a group of more than 2,000 Swiss women aged 64 and over to try to force their government to do more about climate change. The Klimaseniorinnen, or Senior Women for Climate Protection, have taken their government to the European Court of Human Rights (ECHR), arguing that its failure to do more to cut greenhouse gas emissions threatens their right to life and health.
When they first launched their legal challenge in Switzerland in 2016, the evidence of heat’s disproportionate impact on women was limited. No longer. In recent years, study after study has shown that women and older people are more susceptible to heat, with women over 80 facing the highest risk. A study by the University of Bern published last month found Switzerland’s 2022 summer heatwave caused more than 600 heat-related deaths — three times the average for the years 2009-2017. The vast majority of victims were over 65 and older women had the highest mortality rate.
Another recent study found that if current trends continue, heat will kill 204,000 women a year in the U.S., India and Nigeria alone by 2050. It also highlighted the double burden that heat imposes on women, who lose more paid working hours to heat, partly because their caregiving responsibilities are so much greater.
The reasons for the greater impact on women’s health are less well researched. The Nature study said it could be partly explained by different age patterns — with women tending to live longer – and that physiological differences and sociocultural factors may also play a role. An earlier study in China found heat caused greater cardiovascular strain on women, while some scientists have suggested that elderly women may be at higher risk of dying because they are more likely to live alone. After a 2003 heatwave killed thousands in France, it emerged that many of the victims were elderly women living alone in top-floor apartments — typically the smallest apartments in Parisian buildings, and the hottest.
Retired Swiss ethnologist Elisabeth Stern is an active member of the Klimaseniorinnen. Speaking on Zoom from her native Switzerland, where she’s been spending her summer hiking in the Alps, the 75-year-old says more work is needed to determine why women are worse hit. “All we know is that [older] men can take heat better than women. But there wasn’t even much research on that when we started,” she says. “We know that often in medicine, the genders are just considered to be the same.”
For Stern, women’s vulnerability to heat is actually a kind of superpower. It has allowed the Klimaseniorinnen to pursue a case that, if successful, could have Europe-wide implications. There’s a phrase she’s used before about older women being agents of change that intrigues me. When I ask her what she means by it, she tells me about a young relative who told her he supposed campaigning against climate change was better than sitting around in a rocking chair.
“I want to change that narrative,” she laughs. “These are old women, and they’re fighting for their own rights, but at the same time they’re not just old women, they’re agents of change. We’re forcing a high court outside our country to make a decision. If that doesn’t make us agents of change then I don’t know what does.”
The women, who are supported by Greenpeace Switzerland, finally had their day in court in March — the culmination of a years-long battle against their government, which has fought them at every stage. The Swiss government argues that decisions on climate policy should be taken by democratically-elected lawmakers and not the courts. A succession of Swiss courts refused to hear their case, prompting them to take it to the ECHR, which is expected to rule by the end of this year.
Officially, the Klimaseniorinnen are fighting for their rights under the Swiss constitution — that’s how they got the court to take their case. Outside the courtroom though, there’s a lot more to their campaign, which they see as addressing the defining problem of our era. They’re using their newfound fame to raise awareness.
“We do feel responsible for the next generation,” says Stern. “And we do want to leave them something that might benefit them. It will not benefit us… statistically speaking, in 10 years, I’m going to be in the ground. But it will benefit, we hope, a future generation.”