Counting the cost of heat: the case for urgent solutions for cities

This report reveals that extreme heat is emerging as one of the most underestimated threats to economic development worldwide, hammering city economies, overwhelming health systems, and falling hardest on women working on the frontlines of a hotter world. 

The report draws on global and regional evidence and grounds it in detailed economic modeling of four cities chosen for their sharply different climates and heat profiles: Ahmedabad in India, Bangkok in Thailand, Monterrey in Mexico, and Freetown in Sierra Leone. Across the four modeled cities, heat already drains as much as 4 to 8% of city GDP in an average year and claims more than 1,000 lives. At the global level, informal sector women who bear a disproportionate burden, lose an estimated $57 billion in earnings each year to extreme heat (which represents 4-11% of their wages). Without targeted action, those impacts are projected to intensify three- to fivefold by 2050, driven by climate change, rapid urbanization, and ageing populations.