In an article discussing subway conditions in major cities, particularly New York, researchers at Northwestern University, Giorgia Chinazzo and Alessandro Lotta Loria, analyzed social media complaints about thermal discomfort in the subway systems of New York, Boston, and London. Their study, published in Nature Cities, reveals that subway stations can reach dangerous temperatures, often exceeding 100°F (38°C), especially during summer peak hours.
Instead of conducting traditional surveys, the researchers crowdsourced data by examining over 85,000 online posts mentioning heat-related discomfort from 2008 to 2024. Their findings confirm that underground temperatures can often exceed surface heat records, with some London Underground readings reaching as high as 116°F (47°C).
The analysis indicates that complaints are most frequent on weekdays during commuting hours, highlighting the need for cities to plan for extreme heat impacts on public transportation. The study emphasizes that elevated underground temperatures not only threaten commuter health but can also damage infrastructure and ecosystems.
The researchers call for expanded access to data on subway environmental conditions to aid city officials in developing real-time control strategies. They argue that as climate change exacerbates extreme temperatures, such measures are vital to protecting public health and safety.
