There were 56% more heat-related deaths in women than in men during the summer of 2022, once life expectancy had been factored in, according to analysis.

Still, only looking at death tolls is “myopic”, or short-sighted, according to Ronita Bardhan, environment and health professor at Cambridge University.

There are no significant physiological differences in how both sexes cope with heat. Instead, social factors can make women more vulnerable to its effects, Bardhan told The European Correspondent (TEC).

Everything starts with where you live. Living in an uninsulated flat in a densely populated area means heat accumulates inside the home during a heatwave, even if it has air conditioning. “If your building cannot flush out the heat trapped during the day, you are practically inside an oven,” Bardhan said.

In Barcelona, older, less heat-adapted housing built between the 50s and 80s are predominantly inhabited by women, according to IDRA.

Looking for some shade outside should help, right? Well, first, green areas are not distributed equally in urban spaces: neighbourhoods with lower income as well as those in the cities' peripheries tend to have significantly less shady pavements, analysis published last February showed. And even when cities have a high share of shade, wealthier areas benefit disproportionately.

Second, women in vulnerable households generally spend more time at home, because they still shoulder most of the responsibilities like childcare, caregiving, and domestic labour in general, Bardhan told TEC.

Women are also what Bardhan called “shock absorbers”: they tend to put their families’ needs above their own, and that includes protecting them from the heat before they protect themselves.

A lack of data also contributes to women's invisibility. There is a tendency to “design for the average”, Bardhan said, which leaves specific population groups behind. “We need more representation in our data to identify different subgroups of populations who might be at risk” and to then design heat protection solutions based on their needs.

There are even more terrifying and extreme ways in which the heat can be gendered, according to findings by the Cooltorise project funded by the European Commission. Some women were left trapped inside their homes during the hottest hours while their partners took the AC remote control with them, Cristina Ramos, co-director of Ecoserveis, one of the companies developing the project in Barcelona, told us. “That’s another form of gender violence,” she added.

“Money can also be a tool for abuse within the context of heat,” Ramos explained. “Women sometimes are seen as overspending by their male partners, because they are the ones making sure that the temperature in the house is right, whether that means buying curtains and blinds, or turning the AC or the ventilator on. Men usually go out to work and don’t see the need for all this.”