Extreme heat is making some of the world’s poorest women poorer.

That is the stark conclusion of a report, released Tuesday, by the United Nations Food and Agriculture Organization, based on weather and income data in 24 low- and middle-income countries.

The report adds to a body of work that shows how global warming, driven by the burning of fossil fuels, can magnify and worsen existing social disparities.

What does the report find?

The report concludes that while heat stress is costly for all rural households, it is significantly more costly for households headed by a woman: Female-headed households lose 8 percent more of their annual income compared to other households.

That is to say, extreme heat widens the disparity between households headed by women and others. That’s because underlying disparities are at play.

For instance, while women depend on agricultural income, they represent only 12.6 percent of landowners globally, according to estimates by the United Nations Development Program. That means women-headed households are likely to lack access to essential services, like loans, crop insurance and agricultural extension services to help them adapt to climate change.

The report is based on household survey data between 2010 and 2020, overlaid with temperature and rainfall data over 70 years.

The long-term effect of global warming is also pronounced. Female-headed households lose 34 percent more income, compared to others, when the long-term average temperature rises by 1 degree Celsius.

The average global temperature has already risen by roughly 1.2 degrees Celsius since the start of the industrial age.

Flooding similarly suppresses the incomes of female-headed households more than it does other kinds of households, according to the report, but to a lesser degree than heat.

“As these events become more frequent, the impacts on peoples’ lives will deepen as well,” said Nicholas Sitko, an economist with the Food and Agriculture Organization and the lead author of the report.

Why does it matter?

There’s been growing attention in recent years to the disproportionate harms of extreme weather, sometimes aggravated by climate change, on low-income countries that produce far less greenhouse gas emissions, per person, than wealthier, more industrialized countries.

What is less often discussed are inequities within countries. Gender disparities are often the hardest to quantify.