Urban heat is more than just a matter of temperature. It can affect how people sleep, work, move around the city, and dress—and even how safe or comfortable they feel in public spaces. However, these everyday consequences often remain invisible in conventional studies of urban heat.
A new study by an interdisciplinary team from Julius-Maximilians-University Würzburg, the German Aerospace Center (DLR), and Mendel University in Brno examines the human dimension of urban heat using Mexico City in 2022 as a case study. By linking climate, remote sensing, and demographic data with geolocated posts from social media, the researchers from the field of geolingual studies were able to determine a threshold at which heat becomes an important topic in public discourse.
For the study, the scientists combined satellite observations, measurements from weather stations, information on urban spatial structures, census data, and social media posts. In this way, they wanted to find out how and where urban heat affects the residents of the Mexican capital.
The researchers identified a clear threshold. As soon as the air temperature exceeded 25 degrees Celsius, the number of heat-related posts from Mexico City on social media increased exponentially, explains the study's lead author, Dr. Richard Lemoine-Rodríguez. Above this value, heat becomes a more prominent public issue. Furthermore, a particularly large number of posts about the high temperatures originated from hotter and more densely populated parts of the city.
Online discussions reveal that heat affects numerous aspects of daily urban life. Health problems and heat stress were frequently discussed. Users reported exhaustion, insomnia, physical discomfort, and emotional strain. Working conditions were also addressed. People described inadequate cooling in the workplace and complained that they were not allowed to wear shorts despite extreme temperatures. In some cases, they demanded that work under such conditions be suspended.
For women, the heat could also be associated with unwanted attention and harassment. Some reported wearing lighter clothing to cope with the high temperatures, but this resulted in increased harassment. Thus, an adaptation strategy to the heat became an additional burden for them.
Other contributions focused on public transport and urban infrastructure. Issues raised included delays, unpleasant journeys, and inadequate ventilation or air conditioning. Some users described situations where they had to choose between heat and air pollution: opening a window to cool down simultaneously exposed them to more polluted air.
The discussions also addressed cooling options, the use of air conditioning, and providing water for birds, pets, and other animals. Some contributions drew a connection between heat, social inequality, and climate change.
This study originated within the research field of Geolingual Studies, which is currently being developed at the University of Würzburg. This research approach links linguistic utterances with spatial information. The combination of remote sensing, linguistics, digital humanities, and geography makes it possible to examine urban heat not only spatially, but also in its social and everyday impacts in a more nuanced way.
Satellites and weather stations can show where it is hot and how high the temperatures are. However, they cannot capture whether people are unable to sleep because of the heat, have difficulties at work, feel unsafe, or suffer on their daily commute through the city, explains Professor Hannes Taubenböck. This is precisely the central focus of the study: shifting the focus from measured to experienced heat.
By combining physical measurements with data from social media, the authors were able not only to determine where heat occurs, but also to investigate the specific problems it causes in people's everyday lives. The study thus demonstrates the potential benefits of a more human-centered approach to climate change adaptation.
This summer in Europe, and particularly in Germany, has once again demonstrated how dramatic the consequences of heat waves can be. These range from reduced quality of life and economic damage to a high number of heat-related deaths. According to researchers in Würzburg, simply knowing the temperature distribution is therefore insufficient for adapting cities. It is also essential to understand what heat means for people in their daily lives.
original publication
R. Lemoine-Rodríguez, H. Debray, C. Biewer, L. Inostroza, and H. Taubenböck, “From Measured to Experienced Heat: A Multimodal Analysis of Temperature, Urban Form, and Social Media in Mexico City,” in IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, doi: 10.1109/JSTARS.2026.3728299.
