First study to use crowdsourced comments to assess effects of heat underground. Researchers collected comments from X and Google Reviews published between 2008 and 2024. Study focused on subway systems in Boston, New York and London. As above-ground temperatures rise, below-ground thermal complaints increase. Knowing when people are uncomfortable could inform targeted interventions.
If you ever been on a Chinese subway or metro, it’s the total opposite. In summer it’s almost too cold. So maybe western countries have this problem, but in China the subway is amazingly clean, new, comfortable and reliable. In Shanghai alone, there are an average of 11 million passengers a day so it better be good.