Integration of age-friendly city concepts is essential for creating inclusive urban environments that support health and well-being. Older adults are particularly vulnerable to heat stress due to their physiological sensitivity, with prolonged heat exposure potentially causing discomfort, anxiety, and severe health outcomes. Such conditions can also alter behaviour, increasing the risk of social isolation and depression. Few studies have explored how inter-urban spatial variation intersect with health, behaviour and mortality in vulnerable groups. This work addresses this gap by analysing high-resolution spatial data at the neighbourhood level to investigate variations in mortality, behavioural patterns, and risk perception among older adults in Sweden. We employ an innovative approach by combining survey and national mortality data with local spatial characteristics (e.g tree canopy coverage, building density, and proximity to water), to examine behaviours, heat perceptions and mortality rates during heatwaves.  The results show that older adults residing in areas with higher tree canopy coverage were less likely to avoid outdoor activities and perceive problems with indoor heat during heatwaves.  Furthermore, preliminary findings suggest an increased mortality rate in areas with low tree canopy coverage compared to high during warm weather. This highlights the importance of having high tree canopy coverage in residential areas to maintain outdoor activities, reduce problems with indoor heat and heat related mortality among older adults.  Capturing personal experiences and perceptions of public spaces is critical for designing climate-resilient cities that meet the needs of aging populations. Furthermore, the integration of in-situ data with high-resolution spatial datasets provides robust evidence supporting the need for climate adaptation in urban environments.

How to cite: Lönn, J., Thorsson, S., Lindberg, F., Hansson, I., Åström, C., Bjälkebring, P., Gustafsson, S., and Kivi, M.: Urban Heat Stress and Aging Populations: Investigating the Impact of Spatial Characteristics on Health, Behaviour, and Perception, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-174, https://doi.org/10.5194/icuc12-174, 2025.

Populations are more exposed to heat as heatwaves become more frequent, more severe and longer. Urban areas are particularly vulnerable to heat, given urban density, microclimates and the concentration of aged population. Since thermal percepts determine behaviours and adaptive capacities, understanding percepts appears key for assessing heat vulnerability and adapting prevention strategies. However, thermal percepts involves more than just thermal sensation. They encompass the processing and cognitive integration of all sensory stimuli that allow individuals to evaluate their thermal environment. Hence, the present contribution discusses the relationship between climatic parameters and thermal percepts, and highlights the factors influencing them. This work focuses on elderly women, which are particularly vulnerable to heat.

A field survey was carried out during the summer of 2023. The interdisciplinary survey included a thermal monitoring of dwellings, daily follow-up through diaries, and several semi-structured interviews with six women over 70 years old. On this basis, Spearman correlation coefficients were calculated between daily thermal percepts marks and the dwellings temperature and humidity, as well as with weather data from a peri-urban weather station, aggregated daily (mean, maximum, and minimum values). Correlations were then analysed in light of the recorded detailed interviews.

Results highlight no single correlation between thermal percepts and climatic parameters. Rather, significant differences are observed between individuals and between overheating periods. In relation to semi-structured interviews, these differences can be particularly explained by the perceived vulnerability and experienced physical symptoms. Various other factors were also highlighted as impacting on thermal percepts: time of day, sensory experiences of the place, activities performed, mental representations, expectations and overall well-being. Therefore, the multisensory and multifactorial nature of thermal percepts should be considered when assessing individuals' vulnerability to heat and designing prevention strategies.

How to cite: Sondaz, C., Harpet, C., Kuznik, F., and Merlier, L.: Thermal percepts are multifactorial: a cross analysis of thermal monitoring data and qualitative surveys on elderly women in a French metropolis during heatwaves, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-187, https://doi.org/10.5194/icuc12-187, 2025.

Urban parks are generally acknowledged to alleviate thermal stress, as they provide a cooling effect on hot days through transpiration and shading by tree crowns. However, in temperate climate their potential to improve residents’ thermal comfort varies throughout the year. Seasonal fluctuations in tree foliage and related changes in biothermal conditions will affect the perception of the thermal environment of green area users.

In this study we aim to determine how the thermal perception of Warsaw parks visitors varies depending on the type of vegetation and the shading it provides in the summer and transitional seasons. Almost 2800 respondents were surveyed in the six selected urban greenery complexes. In every location, thermal perception research and biometeorological measurements were carried out at least at two sites – in full sun and in the shade of trees. Individuals’ thermal comfort assessment and preferences towards particular weather elements were compared with measured meteorological parameters and UTCI values concerning the Sky View Factor, tree crown cover in a 50 m radius and vegetation types in each site. The possible impact of actual physical activity, thermal history and clothing of interviewees on their thermal sensations was also controlled. The biggest differences in thermal sensations (TSV) between sun-exposed and shaded locations were recorded in the summer – shade decreased perceived thermal conditions by approximately 0.5 point on the 7-point scale.

The results of our study provide a better understanding of how different park arrangements can affect residents' thermal perception and can help city authorities design and revitalize green areas to better adapt to climate change in the temperate climate zone.

How to cite: Lindner-Cendrowska, K., Kuchcik, M., Czarnecka, K., Baranowski, J., Derwisz, K., Jarocińska, A., Kowalska, A., and Słowińska, S.: The influence of vegetation and shade on thermal comfort perception among urban park users in the central European city – the case of Warsaw, Poland., 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-273, https://doi.org/10.5194/icuc12-273, 2025.

PURPOSE: Extreme periods of high or low ambient temperatures are expected to occur more often with climate change. Such environmental conditions could influence habitual physical activity patterns. This study examined the impact of ambient temperature on physical activity levels of Dutch adults and explored the effect of the built environment on this relationship.

METHODS: Physical activity behavior was objectively monitored during 8 consecutive days of cold (<10°C), mild (10-20°C), and warm (>20°C) ambient conditions using a triaxial accelerometer (ActivPAL, PAL Technologies Ltd., Glasgow, UK). Daily levels of light physical activity (LIPA), moderate-to-vigorous physical activity (MVPA), sitting time, and step count were assessed. Green and grey areas in the built environment were classified using the Normalized Difference Vegetation Index, with >0.2 being classified as green. Ambient temperatures were recorded by standard weather stations.

RESULTS: 111 participants (63±11 years, 56% male) were included in this study. Mean ambient temperatures were 13.9±3.6°C (range 10.4-19.4°C) and 25.9±2.9°C (range 22.8-29.8°C) for the mild and warm conditions, respectively, and data will be collected during the 2025 winter for the cold condition. Daily sitting time was higher in the warm versus mild condition (9.4±1.5 h versus 9.2±1.3 h; p=0.04), whereas LIPA (277±71 min versus 279±63 min), MVPA (98±35 min versus 101±35 min), and step count (12,561±4,418 steps versus 13,063±4,297 steps) did not differ. There were no differences between grey and green areas for any of the activity characteristics.  

CONCLUSION:  A higher daily sitting time was observed in warm compared to mild environmental conditions, whereas no differences in other habitual physical activity patterns were observed. Moreover, environmental characteristics did not impact physical activity patterns. These findings suggest that global warming may contribute to a more sedentary lifestyle.

How to cite: Peggen, M., Bongers, C., Vloet, J., Bambacht, R., Hopman, M., and Eijsvogels, T.: Impact of environmental conditions on physical activity behavior in the Netherlands, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-415, https://doi.org/10.5194/icuc12-415, 2025.

Over the past decade, human bio-meteorological research has increasingly examined the link between walkability and thermal comfort in urban environments. Traditional studies have focused on street-level thermal conditions, but recent research highlights how conventional methods misrepresent pedestrians’ actual exposure due to microclimatic variations along their walking route. Recently the concept of “thermal walks,” has been applied to examining pedestrians' dynamic thermal sensations as they move through the complex urban morphology.

This study examines (1) the relationship between urban morphology and pedestrians' dynamic thermal sensation in hot climates and (2) the impact of walking duration and distance on thermal perception. Field campaigns were conducted in Tel Aviv during both summer and winter across six street types: two commercial streets, two boulevards, and two side roads. Walking groups of 4 to 10 participants reported their thermal sensation votes (TSV) at four checkpoints along their routes, while simultaneous meteorological data—including air temperature, humidity, wind speed, and direction—were recorded using Kestrel 5400 Heat Stress Trackers. In total, 1,440 TSV responses were collected. PET and mPET thermal indices were calculated using RayMan Pro.

Results showed that mPET more accurately predicts thermal sensations during the thermal walk than PET. TSV varied significantly across different street types, increasing with walking distance. However, the relationship between TSV and objective thermal sensation weakened as walking distance increased, even with minor microclimate changes. Box plot analysis revealed that longer distances reduced TSV variability among participants.

These findings emphasize the need to incorporate dynamic thermal experiences into urban planning and bio-meteorological research, particularly in hot climates.

How to cite: Potchter, O., Cohen, P., Mandelmilch, M., Omer, I., and Matzarakis, A.: Variation in Thermal Sensation and perception during thermal walk in a Mediterranean City, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-477, https://doi.org/10.5194/icuc12-477, 2025.

Heat stress has been recognised among the key priorities in guiding future climate change adaptation planning. Given the cities’ diverse vulnerability profiles, heat adaptation measures need to be tailored to address the needs of different socio-economic groups and urban settings (IPCC 2022, EEA 2023). To adequately explore this, within the framework of the urbisphere project (coupling dynamic cities and climate) we conducted household surveys in the cities of Stuttgart and Berlin with more than 560 household responses from each city. Both cities have faced an increasing number of hot days and tropical nights in recent years. We explore patterns in perceived heat stress and adaptation options across the two cities through a survey-based analysis while linking the results with different Urban Structure Types (USTs). The questionnaire covers a range of factors, including risk perception and risk awareness, availability of and access to green spaces, and heat adaptation measures employed by residents. By analysing the households’ experience of heat stress and adaptation options in selected areas of the cities and within different USTs, we highlight correlations between building typologies, social structures and perceived heat that influence practical adaptation options in Berlin and Stuttgart. The results highlight that adaptation strategies to buffer heat stress, such as access to shaded green spaces, vary across different socio-economic groups and USTs. We further emphasise that in both cities existing adaptation plans for heat stress need to sufficiently account for interlinkages with human vulnerability and adaptive capacities, which are critical determinants of overall urban heat risk.

How to cite: Ravan, M., Iqbal, N., Birkmann, J., Mack, S., and Hertwig, D.: Comparative Assessment of Human Vulnerability and Adaptation Measures influencing Perceived Heat Stress: Case Study of Stuttgart and Berlin, Germany, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-479, https://doi.org/10.5194/icuc12-479, 2025.

This study examines how extreme urban heat affects the social and mental well-being of communities in informal settlements in Southeast Asian megacities, particularly Quezon City and Bangkok. In a region with persistently high temperatures, residents often view extreme heat-as-usual, reducing the urgency for effective risk management. Low-income populations in informal settlements face unique challenges due to this heat exposure. While the coping strategies they employ aim to alleviate impacts, they often worsen vulnerabilities, causing significant mental health strain, including increased anxiety and distress linked to socioeconomic issues. Additionally, the financial burden of these strategies heightens mental well-being challenges for residents. The study uses a mixed-methods approach: surveys quantify residents’ perceptions and coping strategies, while focus group yield more profound insights into their lived experiences. This research highlights the necessity of understanding the perceptions of vulnerable populations to develop equitable interventions. Findings show that risk perceptions influence coping behaviours and participation in community initiatives. While communities recognise the risks of extreme urban heat, their responses are often reactive, underscoring the need for better engagement and targeted initiatives from the local authorities. By linking risk perception and mental well-being, this study assists in creating urban planning and policies that address the challenges of informal settlement communities adapting to climate change and extreme urban heat.

How to cite: Macagba, S. F. A. and Delina, L.: Extreme Urban Heat Risks and Their Impacts on Mental Well-Being: Lived Experiences and Survey Results from Southeast Asia’s Informal Settlements, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-103, https://doi.org/10.5194/icuc12-103, 2025.

About two hundred thermal indicators exist and yield divergent assessments of heat stress impacts and mitigation. Thus, examining how these indicators respond to various meteorological variables and exploring the implications for their practical use is imperative. Using a correlation analysis, we cluster common indicators into three types: 1) human energy budget models, 2) integrated weather indices, and 3) thermal perception indicators. Distinct extreme hot conditions are identified differently by the various clusters of indicators: human energy budget models are more responsive to micro-scale variation in wind and radiation; while integrated weather indices mainly capture synoptic moist heat extremes. These biophysical indicators also do not concur with a metamodel of thermal perception, developed here using a meta-analysis of coefficients in existing thermal sensation vote equations. The developed thermal perception metamodel is more sensitive to radiation fluxes than other thermal stress indicators. It implies that humans’ thermal sensation may underestimate humid heat stress at nighttime, which can pose a significant risk to human health in hot, humid cities such as Chennai (India) and Dakar (Senegal) and across the Global South. These findings deepen our understanding of heat stress variability on humans and provide a framework for selecting suitable indicators in future applications.

How to cite: Huang, X., Kong, Q., Wang, Z.-H., Li, P., Middel, A., Matzarakis, A., Nikolopoulou, M., Huber, M., Vanos, J., Song, J., Li, D., Manoli, G., Pisello, A. L., and Bou-Zeid, E.: The diverging predictions of extreme heat risk indicators, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-483, https://doi.org/10.5194/icuc12-483, 2025.

Extreme urban weather generates unequal impacts on human health and well-being, with transit stops often serving as critical points of exposure to extreme micro-climatic conditions. These locations are essential for urban mobility, particularly for transit-dependent riders, often among the most vulnerable and economically disadvantaged populations. However, transit stops frequently lack adequate protection against heat, leaving riders exposed to potentially hazardous thermal conditions. This study investigates the intersection of biophysical and social dimensions of extreme heat at transit stops in Denver, Colorado, USA.

A representative sample of 125 bus stops was selected to capture variability across physical attributes (e.g., vegetation cover, impervious surfaces, and built land cover) and socioeconomic gradients (e.g., income levels and racial/ethnic demographics). Summertime mean radiant temperature was measured at these stops using low-cost weather stations. These observations were used to characterize physical drivers of heat exposure, including micro- and neighborhood-scale land cover interactions, transit infrastructure design, and synoptic weather patterns. In parallel, rider perceptions of heat and its influence on transit behavior were assessed through structured surveys and detailed ridership data from individual bus stops.

Preliminary results provide insights into rider experiences and behavior under heat stress and highlight key physical drivers of extreme heat. These findings offer actionable recommendations for transit authorities to evaluate the effectiveness of current shade structures, prioritize infrastructure upgrades, and develop targeted heat mitigation strategies for transit users.

How to cite: Crawford, B., Dzwonczyk, L., Ibsen, P., Medisetti, B., McHale, M., Steinharter, L., and Troy, A.:  Perceptions and physical drivers of extreme heat at transit stops, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-505, https://doi.org/10.5194/icuc12-505, 2025.

During summer, office workers and students in Japan frequently transition between air-conditioned indoor spaces and hot outdoor environments. However, the impact of short outdoor walks on subsequent indoor cognitive performance remains unclear. This study examines how exposure to a heat-stressful outdoor environment affects cognitive performance in an air-conditioned setting.

A total of 96 participants completed a mathematical addition test before and after a 15-minute walk in an outdoor environment where the Universal Thermal Climate Index (UTCI) exceeded 44°C. The results showed a 3.6% decline in cognitive performance, measured as the percentage of correct answers relative to problems solved, following heat exposure. This decline was more pronounced in participants who had slept less than five hours, particularly among men. Sleep-deprived men exhibited the most significant cognitive impairment after heat exposure, highlighting the combined impact of insufficient sleep and heat stress.

To explore potential mitigation strategies, a follow-up field experiment with 46 participants assessed the effectiveness of shade from street trees and UV parasols. Cognitive performance remained stable after walking under street trees but declined by 1.3% in direct sunlight and 1.2% under UV parasols. These findings suggest that street trees effectively mitigate heat-induced cognitive decline, whereas UV parasols offer limited protection. Additionally, participants who had sufficient sleep experienced a smaller decline in cognitive performance, underscoring the importance of adequate sleep as a complementary protective measure.

This study provides key insights into environmental and behavioral strategies for maintaining cognitive performance in extreme urban heat, offering valuable guidance for urban planning and personal heat adaptation.

How to cite: Asano, Y., Nakamura, Y., Suzuki-Parker, A., Aiba, S., and Kusaka, H.: Effects of Short Outdoor Walks on Indoor Cognitive Performance and Potential Countermeasures, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-521, https://doi.org/10.5194/icuc12-521, 2025.

In Japan, with its warming and aging population, there is an urgent need to reduce the number of heatstroke sufferers. This can be achieved effectively and efficiently by identifying vulnerable socioeconomic factors in Japan and approaching measures. Surveys were conducted to implement effective countermeasures to vulnerable attributes.

A survey was conducted among 10,000 elderly people in Kawasaki City. A chi-square test was conducted to examine the relationship between history of heatstroke, socioeconomic factors, and heatstroke countermeasures, with P<0.1 as significant. Newly identified vulnerable socioeconomic factors in the survey were built 24 years or more ago (OR2.16), wooden structure (OR1.60), means of information gathering (radio (OR1.56)) and underlying medical conditions (diabetes (OR1.81)). Effective measures were found to be “hydration of at least 1.2 L per day almost every day” (OR1.61) and “hygrometer use” (OR3.46). In addition, the respondents were more likely to suffer from heatstroke if the information was collected via radio and less likely to suffer from heatstroke if the information was collected via a website. The number of emergency medical evacuations was expected to decrease by up to 102 (18.5%), 86.1 (15.2%), and 48.4 (8.74%) persons, respectively, when “hygrometer use” was practiced by males, persons requiring long-term care, and patients with dementia.

A similar survey was conducted on 3,523 residents of a municipal housing complex, and vulnerability factors were found to be household income of less than 1.5 million yen (OR 2.07), certification of need for nursing care (OR 6.54), and suspected dementia (OR 1.96). Suggested that groups with lower incomes have unique vulnerability factors.

The results suggest that a person is less likely to suffer from heatstroke if he or she maintains an environment that is less prone to high temperatures, hydrates himself or herself with sufficient amounts of water daily, and is proactive in obtaining information.

How to cite: Inazawa, T., Tsurumi, K., Kondou, R., Tanaka, T., Ihara, R., and Ihara, T.:  Examining the Relationship Between Heatstroke Incidence, Socioeconomic Factors, and Preventive Measures in Kawasaki, Japan, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-526, https://doi.org/10.5194/icuc12-526, 2025.

Extreme heat has been the leading cause of weather-related mortality in the United States for the past thirty years and is a growing problem under rapidly warming climate conditions. Older people, young children, and those with low income are considered particularly vulnerable but everyone can be at risk. Individuals make a variety of everyday decisions that can protect their health when faced with potential extreme heat exposure. On the shortest timescales and with the least investment, these adaptive actions may simply protect one’s own health or the health of ones’ family (e.g. staying hydrated, changing plans, checking on neighbors). At medium time and investment scales adaptive actions may also have broader energy system implications (e.g. using air conditioning or fans, or going to a cooling center or public air conditioned space). And, at the longest time scales and with the most investment, heat-health adaptive actions may have implications for public health, energy and infrastructure systems (e.g. installing air conditioning, home weatherization, and migration or displacement). As the climate continues to rapidly warm differentially around the globe, regional variation in the public perception of heat-health risk and tolerance for adaptive action is required to understand the implications of this threat on public health, and to make projections for future energy and infrastructure systems. The typology of everyday heat-health behaviors will be illustrated using evidence from an online stratified survey of Vermont, USA residents (N = 1818) that was conducted in the late summer of 2022 using social-psychological theories of behavior change including the theory of planned behavior and the transtheoretical model of behavior change. Broader system implications are be extrapolated.

How to cite: Doran, E.: A Typology of Everyday Heat Health Behaviors and Implications for System Sustainability Across Scales, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-555, https://doi.org/10.5194/icuc12-555, 2025.

Climate change has intensified the Urban Heat Island Effect (UHIE), disproportionately impacting vulnerable urban populations. While Heat Vulnerability Indices (HVIs) and Heat Action Plans (HAPs) aim to mitigate these effects, the lack of community engagement in understanding perceptions and adaptive behaviors creates a disconnect between policies and ground realities. This study bridges this gap by examining how vulnerable communities in Delhi perceive and cope with urban heat stress, aligning mitigation strategies with their firsthand experiences and traditional practices.

A random sampling-based in-person, semi-structured survey was conducted from May to July 2024 across five highly vulnerable neighborhoods in Delhi identified through an HVI. These areas, home to low-income groups, minorities, and marginalized communities, were assessed for their socio-cultural, infrastructural, and urban design contexts. The survey (n=56) included participants from diverse occupations such as outdoor workers, small-business owners, and vendors, with 78% aged 18–60 years and 20% above 60 years.

Findings revealed that 51% of participants experienced heat stress disruptions in daily routines, while 64% reported increased health-related expenses, particularly among daily wage earners. About 55% suffered from dehydration, headaches, and heatstroke, alongside psychological stress. Adaptation strategies included adjusting work hours, seeking shade in local parks (often poorly maintained), or traveling to greener areas in wealthier neighborhoods.

Community-driven initiatives played a crucial role in coping with extreme heat, rooted in cultural traditions of mutual aid. Examples include public pyaus (earthen pots) offering free water, gurdwaras distributing rose milk and water as part of Sikh sewa (selfless service), and mosques providing free food and water during heatwaves.

This study highlights the need to integrate community-driven adaptations, traditional knowledge, and local perceptions into heat resilience policies. Strengthening green infrastructure and scaling grassroots initiatives through government-community collaboration is essential for sustainable urban heat mitigation.

How to cite: Gangrade, S. and Dhariwal, J.: Urban heat through local lenses: Perception, Adaptation and Community-driven resilience, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-592, https://doi.org/10.5194/icuc12-592, 2025.

Outdoor thermal comfort significantly shapes human experience in urban open spaces. This study examines the relationship between micrometeorological conditions, thermal perception and affective response in Chandigarh (30°44′11″N, 76°47′18″E), India, a city characterized by a humid subtropical climate. The study was conducted in Zakir Hussain Rose Garden and Shanti Kunj during summer 2022. Micrometeorological parameters, including dry-bulb temperature (Ta, °C), globe temperature (Tg, °C), relative humidity (RH), and air velocity (V, m/s), were measured while Physiological Equivalent Temperature (PET) and mean radiant temperature (T_mrt, °C) were computed. Affective responses were evaluated through the Positive and Negative Affect Schedule (PANAS), while thermal perception was examined through concurrent comfort surveys. A total of 393 respondents completed the PANAS questionnaire, reporting positive affect (PA) and negative affect (NA) scores, alongside thermal perception.

Results indicate a strong negative correlation between PET and PA scores, demonstrating diminishing positive emotions with increasing thermal discomfort. Conversely, NA exhibited a weak but significant positive correlation with PET, particularly in low-shade environments, suggesting a higher likelihood of negative emotions under extreme heat.

Landscape morphology and shading characteristics significantly influenced thermal perception and PA. Sky view factor (SVF) correlated negatively with PA, while visible green index (VGI) correlated positively, highlighting respondents' preference for shaded and vegetated spaces. Additionally, respondents perceiving the thermal environment as acceptable reported higher PA and lower NA scores, reinforcing the psychological benefits of thermally comfortable outdoor settings.

These findings highlight the psychological implications of urban heat exposure, emphasizing the role of green infrastructure, shading, and microclimate-sensitive landscape design in enhancing outdoor comfort and well-being. This study offers empirical insights into urban heat perception and emotional responses, informing the climate-responsive design of public spaces to enhance thermal equity and psychological well-being in Indian cities in the face of escalating heat stress.

How to cite: Suneja, M.: Heat, Shade and Mood: Linking Thermal Comfort to Emotional Response in Urban Green Spaces., 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-609, https://doi.org/10.5194/icuc12-609, 2025.

Record-breaking heatwaves in recent years have significantly altered travel demand, mode choice, and travel behavior, underscoring the need to integrate heat mitigation strategies into the promotion of active travel and public transit. While existing studies have examined passenger flow dynamics at subway stations during extreme heat events (EHEs), limited attention has been given to differences in travel purposes and the disproportionate effects on vulnerable groups.

This study investigates the dynamic changes in subway ridership during EHEs in New York City, home to one of the world’s largest and busiest transit systems. Specifically, we analyze variations in ridership based on trip purposes (utilitarian vs. recreational), temporal diurnal fluctuations, and the experiences of low-income groups, seniors and people with disabilities. By identifying stations with minimal ridership fluctuations during EHEs, we classify them as more resilient and explore how the built environment influences resilience to heat stress.

Our findings reveal that the negative impacts of EHEs are more pronounced on weekends than weekdays, with senior and disabled passengers experiencing the most significant declines, particularly during midday hours. While passengers using fair-fare plans are not significantly more affected overall, time-specific variations emerge. For general passengers, evening hours see the largest ridership declines, whereas fair-fare users exhibit minimal variation across the day. On weekdays, ridership decreases more at underground stations and those surrounded by higher densities, residential or industrial land, open spaces, and bicycle racks. On weekends, stations in areas with mixed land use experience greater ridership drops.

This study provides a station-level evaluation of ridership fluctuations during EHEs and highlights the potential of metro design to mitigate heat stress. The findings offer actionable insights for developing inclusive, heat-resilient transit systems and improving emergency planning to better support vulnerable populations.

How to cite: Zhao, M. and Li, W.: Disparities in the Impacts of Extreme Heat Events on Metro Ridership: Evidence from New York City, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-612, https://doi.org/10.5194/icuc12-612, 2025.

The urban heat island (UHI) effect leads to substantial health risks for urban dwellers. A significant increase and intensification in heat exposure is expected due to climate change. A key cause for the UHI is the large proportion of low albedo and impervious surface materials. To increase thermal comfort and reduce heat stress, nature-based solutions including green infrastructure are often proposed. Unsealing strategies such as grass grid pavers (GGPs) can support heat mitigation and contribute to reducing surface flow without requiring additional space. However, GGPs cannot be installed everywhere and require high installation and maintenance costs. Thus, our research aims to realistically assess the efficacy of GGPs for cooling urban areas, considering limitations like implementation suitability. In addition, factors such as ventilation and irradiation have a strong impact upon the cooling effect. We compared microclimatic effects and thermal comfort improvement of GGPs for shaded and unshaded areas in a densely developed neighbourhood in the city of Cologne/Germany during an extreme heat event by using high-resolution microclimate simulations (ENVI-met). A new parametrization of GGPs based on field measurements was developed. Model performance is assessed using data from a quality-controlled citizen science sensor network. Asphalt and concrete surfaces in the status-quo model were replaced by GGPs. Model outputs show a significant improvement of biometeorological comfort quantified by the Universal Thermal Comfort Index which indicates the change in human heat perception. Physiological Equivalent Temperature is reduced by up to -5.43 K. These findings can support decision-making and optimization of adaptation strategies aiming to improve heat resilience. Modelling the human perception of heat and the effects of adaptation measures has the potential to strengthen citizen participation in the needed transformation process towards climate change adaptation. Pathways for citizen participation are currently researched in the AKT@HoMe project at University of Cologne.

How to cite: Domm, A., Eingrüber, N., Schneider, K., and Dlugoß, V.: Effect of grass grid pavers on thermal outdoor comfort in urban areas - A microclimate modelling study to analyse spatial variability in heat stress mitigation potential in the context of climate change adaptation, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-393, https://doi.org/10.5194/icuc12-393, 2025.

Pedestrians in urban environments are highly susceptible to heat stress, primarily due to intense solar radiation while walking through open spaces. UV parasols are anticipated to serve as a personal method for mitigating heat stress, owing to their portability and ease of use in pedestrian settings. Thorough validation of their effectiveness in mitigating heat stress requires participant experiments that simulate real pedestrian experiences. We conducted meteorological observations and thermal sensory questionnaires to verify the effect of UV parasols in mitigating heat stress among urban pedestrians. To emphasize the distinctive features of UV parasols, we contrasted their effects with those of street trees, which provide fixed shading in urban walking areas. What distinguishes this study is the verification and comparison of the heat stress mitigation effects of UV parasols and street trees through participant experiments, specifically from the perspective of pedestrian comfort. The meteorological observation findings demonstrated that UV parasols decreased the Universal Thermal Climate Index (UTCI) by 3.6 °C compared to direct sunlight, equivalent to approximately 56 % of the reduction achieved by street trees. However, results from the thermal sensory questionnaire survey indicated that the alleviation of heat sensation by UV parasols was only approximately 30 % of that provided by street trees. This limited effectiveness of UV parasols is primarily ascribed to their inability to adequately shield pedestrians' entire bodies from solar radiation while in motion. The experimental outcomes obtained in this study are expected to contribute to the reduction of heat stroke incidents among urban pedestrians and the design of adaptation measures for climate change in pedestrian-centric urban planning.

How to cite: Nakamura, Y., Asano, Y., Suzuki-Parker, A., and Kusaka, H.: Evaluation of Heat Stress Mitigation Effects of UV Parasols through UTCI Observations and Thermal Sensory Questionnaire Survey, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-703, https://doi.org/10.5194/icuc12-703, 2025.

Urban resilience and vulnerability are key concepts for sustainable development in our cities. While most research describes how resilience and vulnerability are linked theoretically, there is a lack of data-driven empirical studies that examine and contextualise their interdependencies in time and space. This study explores the spatio-temporal relationship between resilience and vulnerability during the 2019 European heatwave in the three largest Dutch cities: The Hague, Rotterdam and Amsterdam. Our spatio-temporal analysis reveals a nuanced and highly contextualised relationship between districts' vulnerability profiles and their resilience to heatwaves. First, we identify vulnerability profiles based on demographic, socioeconomic, and health factors. Even though the three case study cities may seem similar, we see significant differences in underlying factors determining vulnerability, confirming the need for contextualised vulnerability assessments. Second, contrary to conventional wisdom, our analysis reveals both negative (more vulnerable, less resilient) and positive (more vulnerable, more resilient) relationships between vulnerability and resilience depending on the time of the day. This finding suggests that relationships are more complex and influenced by citizens' adaptive behaviours by the underlying social and urban fabric. This research highlights the critical role of tailored, dynamic urban planning and response strategies. We argue to move towards an integrated and contextualised assessment of urban resilience and vulnerability.

How to cite: Sirenko, M., Verbraeck, A., and Comes, T.: More vulnerable, less resilient? Insights into the spatial-temporal dynamics of vulnerability, resilience and adaptive capacity from the 2019 European heatwave, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-811, https://doi.org/10.5194/icuc12-811, 2025.

Urban heat stress and noise significantly impact the health and well-being of urban inhabitants. This biometeorological study analyses microclimate, sound, and human perceptions in three vegetative courtyards near Schiphol Airport, Amsterdam. The courtyards operate with sixteen Kestrel heat-stress trackers and six Munisense microphones for year-round microclimate and soundscape monitoring to inform urban design strategies to improve pedestrian thermal and acoustical comfort.

A human measurement campaign was conducted on 23-July-2024, involving 24 student participants (aged 22–28) equipped with skin-temperature sensors (iButtons) and heart-rate wristbands (Polar). They completed mobile questionnaires on ‘right-here-right-now’ comfort perceptions during three transect walks following a stop-and-go protocol (3-minute intervals, total duration: 60 minutes). Walks spanned three courtyards: one with a vertical vegetative wall, another with 36 Tilia × europaea potted trees, and a third featuring a slanted roof with an overhang. The study examines the interplay between heat, noise, and environmental perceptions across courtyard designs.

Findings suggest overhangs provide significant cooling (UTCI -10°C) and noise reduction due to sound shadowing. Slanted roofs scatter aircraft noise (LAeq -5 dB(A)) but have minimal cooling effects. Green walls diffract sound but reflect short-wave radiation, limiting cooling. Trees intercept solar heat effectively but offer limited aircraft noise reduction due to foliage gaps.

Perceptual analyses indicate the tree courtyard offered optimal thermal (TSV) and acoustical comfort (ASV). A mixed-linear regression analysis tested five hypotheses on TSV, ASV, UTCI, and LAeq. One hypothesis was rejected: heat stress and aircraft noise do not confound acoustical perception. Two were partially supported: thermal and/or acoustical perception may confound acoustical perception. Two were fully supported: aircraft noise can confound thermal perceptions and acoustical perception can confound thermal perception.

The discussions and conclusions present evidence-based design and planning strategies to mitigate environmental stressors and enhance pedestrians' psychological and behavioural adaptations to heat and noise in urban environments.

How to cite: Peng, Z., Lugten, M., Wuite, G., Luo, W., and Santucci, D.: Coping with Urban Heat and Noise: A case study at Schiphol Airport, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-816, https://doi.org/10.5194/icuc12-816, 2025.

Rapid urbanisation and changing climate patterns have intensified heat stress in urban areas. Factors such as the Urban Heat Island (UHI) effect, population growth, land use changes, and inadequate green and blue infrastructure contribute to elevated temperatures. The objective of this study is to map heat risks in Bhubaneswar using geospatial indicators, showcasing the potential of open-source satellite imagery to enhance Heat Action Plans (HAPs). Our research methodology integrates satellite imagery and various geospatial data to analyse the drivers and indicators of heat risk based on the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) framework considering Hazard, Exposure and Vulnerability. Comprehensive heat risk maps are generated for Bhubaneswar, an Indian tropical city increasingly experiencing extreme heat and escalating heatwaves. The risk map reveals distinct clusters, including a linear pattern along the railway line, mostly towards the eastern side and a prominent cluster in slum-dominated wards. These maps identify areas with increased exposure and vulnerability, providing valuable insights for developing targeted mitigation strategies. The outcomes of this research contribute to enhancing Heat Action Plan for Bhubaneswar and offer a scalable methodology for assessing heat risks in other cities. The developed framework can be readily applied, facilitating the integration of these assessments into HAPs. Moreover, the study emphasises future plans to collaborate with government authorities and disaster management agencies to incorporate on-ground socio-economic data, further refining the heat risk assessment process.

How to cite: Pritipadmaja, P., Prabhu, S., and Garg, R. D.: Geospatial Indicators for Urban Heat Risk: A Remote Sensing-Based Approach for Bhubaneswar, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-702, https://doi.org/10.5194/icuc12-702, 2025.

Extreme heat events are increasingly occurring in German cities. In dense urban areas in particular, we expect even more intense and frequent heatwaves in the future posing significant threads to people’s health. To gain an understanding of the effects of heat stress and to develop sustainable cooling measures, research has been carried out at a technical, planning and spatial level. However, the topic needs additional attention from a social science perspective. Our experiment explores the fundamental question of which city users experience heat in urban outdoor spaces, in terms of intensity and location. The study was conducted in Berlin in the summer of 2024 with over 30 participants, performed as Climatewalks, microclimatic city walks, in which selected test subjects walk through the city center during a hot day and document their own thermal perception. While environmental factors were measured with a mobile weather station and geolocated, we investigated and mapped both qualitatively and quantitatively the relationship between the built urban environment, microclimate and  people’s thermal perception. This was followed by focus groups to discuss the experience gained from the Climatewalks and to identify new urban requirements from a city users’ perspective. On this basis, we formulated recommendations to act for urban climate adaptation measures with a holistic approach integrating expertise of different domains.

How to cite: Santucci, D., Schroth, J., and Gabriel, J.:  A socio-spatially differentiated analysis to assess citizen’s thermal exposure in Berlin, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-825, https://doi.org/10.5194/icuc12-825, 2025.

The increasing frequency and intensity of heatwaves due to climate change cause a significant challenge to global public health. These extreme heat events are linked to increased morbidity and mortality risks, particularly when ambient temperatures surpass local acclimatization thresholds. Furthermore, the adverse impacts of heatwaves are not evenly distributed; vulnerable subpopulations, including older adults and children, exhibit heightened susceptibility due to inherent physiological limitations. Additionally, research indicates that environmental and socioeconomic factors, such as access to green spaces and income levels, play a critical role in shaping heat vulnerability. These factors influence thermal comfort and affect an individual’s ability to cope with extreme heat. Therefore, to mitigate heat-related health risks, it is essential to assess district-level heat vulnerability in Prague and identify areas where interventions are most urgently needed.

This study employs geographically weighted principal components analysis (GWPCA) to investigate the influence of meteorological variables (mean summer air temperature and the mean number of heatwave days), environmental attributes (the proportion and type of greenery, as well as the urban coverage ratio), and socioeconomic conditions (population demographics, unemployment rate, and average income) on heat vulnerability. Vulnerability is quantified using daily heat-related mortality and ambulance call-out data collected from 2014 to 2020 across Prague’s districts. High-resolution UrbClim model data are utilized to characterize the spatial variability of air temperature. Moreover, a multivariate meta-regression model is applied to quantify the associations between increased temperatures and the risk of mortality and emergency responses, while controlling for district-level characteristics. By identifying the principal determinants of heat vulnerability, this study delineates the areas at greatest risk and supports the development of targeted interventions to mitigate the adverse effects of extreme heat on susceptible populations.

How to cite: Dogan, T. and Urban, A.: Determinants of heat-related vulnerability at the district level in Prague, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-236, https://doi.org/10.5194/icuc12-236, 2025.

Extreme heat is a major public health concern in the hot-arid desert megacity of Cairo, where urban heat island effects continue to intensify heat hazards, which are expected to grow further with climate change. To support health preparedness, this study surveyed 550 pedestrians in Cairo, assessing heat exposure, thermal comfort, and health perceptions while considering socio-cultural factors.

The analysis revealed statistically significant correlations between thermal comfort perception (ASV) and environmental perceptions including humidity (Spearman’s rho, ρₛ=0.242), wind speed (ρₛ=-0.217), solar radiation (ρₛ=0.390), dust conditions (Spearman’s rho, ρₛ=0.183), and skin-wettedness (ρₛ=0.417) perceptions. However, correlations between ASV and measured environmental conditions (air temperature, relative humidity, wind speed and solar radiation) were weak, highlighting subjective biases in environmental assessments and the need to consider socio-cultural factors in public health studies.

The study found a negative correlation (ρₛ= -0.159) between air-quality perception and ASV, suggesting that individuals who perceived higher temperatures also reported lower air-quality. However, measured pollution levels (PM10, PM2.5, CO₂) showed no correlation with ASV, indicating a disconnect between perceived and actual air-quality. No significant relationship was found between environmental parameters and general health satisfaction and quality of life, suggesting that thermal discomfort is not always linked to overall health perceptions.

Further analysis highlighted socio-cultural biases in self-reported health and environmental perceptions, particularly regarding pollution levels and personal health ratings. Individuals accustomed to high pollution may not explicitly acknowledge its impact, and their perception of air quality was not necessarily tied to location.

A Pearson’s Chi-squared test revealed significant demographic variations in thermal comfort perception, with age, gender, and education level strongly influencing ASV scores. These findings highlight the need for targeted health interventions to reduce urban heat vulnerability and emphasise the importance of integrating subjective and objective environmental assessments into urban planning and climate adaptation strategies in Cairo’s evolving urban landscape.

How to cite: Sharmin, T., Khalil, H. A. E. E.-D., Davis, J., Gammaz, S., Hurt, L., Luo, Z., and Lannon, S. and the Tania Sharmin, SharminT@cardiff.ac.uk: Heat-Health Survey for Public Health Preparedness in the Hot Desert Megacity of Cairo, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-949, https://doi.org/10.5194/icuc12-949, 2025.

As heatwaves in cities intensify, understanding how urban residents adapt to extreme heat is critical. Yet, climate literature predominantly focuses on exposure-centric, spatial approaches, while bottom-up, people-first perspectives remain underrepresented. This study employs a sequential mixed-method approach to investigate behavioural adaptation practices among urban dwellers in the Netherlands.

In the first phase of the study, semi-structured, in-depth interviews (n=21) identified key themes that informed a Likert-scale survey instrument employed in the second phase to test a set of hypotheses. Subsequently, in phase two, a nationwide survey (n=1,849) across three urban typologies—Extremely Urban, Strongly Urban, and Moderately Urban—captured perceptions and behavioural practices related to heatwave adaptation.

Findings indicate that residents in highly dense, extremely urban areas have a lower behavioural adaptation score compared to the other two urban types. Additionally, ownership emerges as a key factor in the adaptation process; where homeowners prioritize technological adjustments, renters rely more on personal and cultural adjustments. In terms of risk perception, statistically significant differences exist between adults living alone and those living with a partner or family.

The tested hypotheses provide a nuanced understanding of specific vulnerability to heatwaves in the Netherlands, offering insights that can inform targeted urban design and planning strategies at the local level.

How to cite: Ahmed, I., van Esch, M., Petrović, A., and van der Hoeven, F.: Behavioral Adaptation to Heatwaves in Urban Netherlands: A Sequential Mixed-Method Inquiry, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-1044, https://doi.org/10.5194/icuc12-1044, 2025.

Extreme heat is an increasingly severe public health challenge worldwide, yet heat risks remain underexplored in low-income countries. This study is the first to examine heat risk knowledge, perceptions, challenges, and adaptation strategies in Mozambique, focusing on community members and health professionals in the urban agglomeration of Maputo and Matola City. We conducted a survey (N=95) that combined closed-ended questions with follow-up open-ended responses to explore participants' reasoning. Descriptive analyses of the quantitative data were performed, and open-ended responses were categorized based on emergent themes drawn from participants’ answers. Our results show that participants widely recognized heatwaves as a severe public health threat and a majority perceived themselves as vulnerable. They identified a wide range of common heat-related symptoms, vulnerable groups, and adaptation measures, although many noted barriers that limited their ability to implement common strategies. Respondents also reported persistent challenges to continue working during extreme heat, mentioning reasons such as impacts on health, mental strain, and overall reduced productivity. Specific healthcare challenges due to the heat were also reported, such as increased number of patients, equipment failures, and difficulities in storing medicines. Lastly, although most participants received heat alerts in advance of extreme heat, the messages were found to lack actionable guidance and not always reach all vulnerable groups effectively. In conclusion, our findings underscore the need to strengthen healthcare preparedness, as well as the development targeted interventions which take into account socio-economic disparities in adaptation to heat. 

How to cite: Pereira Marghidan, C., Marrufo, T., Inlamea, O., Blanford, J., Coughlan de Perez, E., and van Aalst, M.: Heat risk perceptions and limits to adaptation in urban Mozambique: insights from communities and health professionals , 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-1056, https://doi.org/10.5194/icuc12-1056, 2025.

During the summer of 2024, a record-breaking heatwave occurred in the Yangtze River Delta urban agglomeration, posed widespread health and socio-economic challenges for local residents. Based on the Weather Research and Forecasting (WRF) model coupled with the Urban Canopy Model (UCM) and observations from 3000 automatic meteorological stations, we assess the heterogeneous contributions of urban effects —particularly land-use changes (LU) and anthropogenic heat emissions (AH) — to this extreme heat wave and further extent to the heat-related morbidity over Yangtze River Delta (YRD). The results quantify the contributions of individual and combined urban effects on the extreme heat wave at 3-km spatial resolution. The urban effects contribute to about 24% on the elevated daily mean temperature averaged across urban areas, with the LU play a more significant role than the AH. At night, urban effects contribute approximately 38% to the elevated surface temperature averaged across urban areas. The maximum contribution of combined urban effects is observed in downtown Shanghai. The contribution of combined urban effects to heat-related morbidity is greater at night than during the daytime, with an average value of 29% across all urban areas and a maximum of 48% in downtown Shanghai at night. These findings offer insights in identifying heat-vulnerable spots within cities and provide detailed information for designing targeted, region-specific strategies to enhance urban resilience and guide adaptive measures to mitigate the impacts of future heatwaves.

How to cite: Yuan, J.: Pivotal Contributions of Urban Effects to the Intensity and Health Impacts of the 2024 Record-Breaking Heatwave over Yangtze River Delta, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-85, https://doi.org/10.5194/icuc12-85, 2025.

The widespread occurrence of heat waves is exacerbating public health risks. Understanding the region where the heatwave occurs, the population it affects, and the extent of its social attention are essential for heatwave preparedness and response. Previous studies have recognized heatwaves as a major health risk, but limited research on the public's perception of heatwaves using location-based social media data. This crowdsourcing approach remains a significant asset in understanding the public's perception of natural hazards, such as heatwaves, and in assessing the potential effects of heatwaves on local communities. Centering on examining the association between public attention and heatwaves, the present study collected social media (Weibo) data, weather data, and other geographical data from open-source platforms, then adopted a BERT-based language model to extract heat-related Weibo tweets from May to September 2024. Using a cumulative heatwave intensity index (HCI), this study investigates the spatiotemporal patterns of public attention to heatwaves and assesses the influence of meteorological, demographic, and socioeconomic variables. Results show that the number of heatwave-related tweets (NHT) peaked at 14:00 and 22:00, supporting the notion that heatwaves exacerbate the impact on human activities during nighttime. High NHT was primarily concentrated in densely populated regions of eastern and southern China, with fewer in the western regions. Clustering analysis using MGWR and K-means++ revealed regional variations in public sensitivity to heat waves. NHT is primarily influenced by socioeconomic and demographic attributes such as GDP per capita, population density, and penetration rate. In contrast, the heat-related tweets (RHTs) ratio is more dependent on environmental factors (e.g., HCI, precipitation, dew point temperature) and population density. Further research is needed to enhance understanding of heatwave perception among different populations. This study has the potential to provide insights into improving population resilience during heat waves using location-based social media data.

How to cite: Liu, S. and Ren, C.: A survey of public perception of heat waves across China: A social media-based geospatial modeling approach, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-99, https://doi.org/10.5194/icuc12-99, 2025.

The risk of indoor overheating is increasingly exacerbated by climate change, placing countries previously less affected, such as the UK, at the forefront of this growing issue. With much of the UK’s housing stock not designed to withstand rising temperatures, concerns about the impact on physical health are mounting. Social housing and low-income households are particularly vulnerable due to inadequate building design and limited access to cooling solutions.

In this study, we employed a multifaceted approach to benchmark indoor overheating by integrating data on home environments and socioeconomic factors. We investigated the influence of variables such as housing conditions and tenure on the extent of overheating. The study was conducted in Southwark, one of the most deprived boroughs in London. Participants from 40 homes took part during the summer of 2023. Sensors were deployed in each home to measure temperature, humidity, and other environmental indices, while surveys were conducted to gather self-reported data on housing conditions, types, and tenure. Using this combined data, the severity of indoor overheating was benchmarked, and priorities for home improvements were ranked.

Furthermore, for the targeted homes, the effectiveness and cost-efficiency of various improvement options were assessed using Urban Building Energy Modelling (UBEM). This analysis provides valuable decision support for local authorities, offering insights into how indoor environments impact health and well-being, particularly in relation to socioeconomic disparities.

How to cite: Zhu, M. and Zhao, Q.: The impact of housing conditions and socioeconomic status on domestic indoor overheating over summer: a study in Southwark, London, UK, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-292, https://doi.org/10.5194/icuc12-292, 2025.

Background and Aim: Heatstroke has become a serious issue in Japan. To reduce the risk of heatstroke, the Japanese government has implemented initiatives such as the “Heatstroke Alert”, which is issued when the wet bulb globe temperature (WBGT) exceeds 33 °C. Although such initiatives employ the WBGT as a standard, other important meteorological indicators may also be related to heatstroke. In this study, we analyzed important meteorological indicators of heatstroke mortality using machine learning.

Methods: We used ICD-10: X30 for heatstroke mortality data. The analysis was performed for two age groups, i.e., the <65- and ≥65-year age groups, across all 47 Japanese prefectures. The assessed meteorological indicators were the daily maximum/minimum/mean temperature, daily precipitation, solar radiation, daily average wind speed, daily average relative humidity, and daily maximum/average WBGT. We also assessed the lag and accumulated heat effects. Furthermore, the parameters RelTemp and RelWBGT, which consider the cumulative temperature/WBGT values from May 1 to the day of incidence, were adopted to express heat acclimatization. To analyze the importance of meteorological indicators, we applied the conditional permutation method, which can deal with collinearity among meteorological indicators, using a random forest approach.

Results: For each prefecture, we ranked the importance of the meteorological indicators for each age group and tabulated the number of times these meteorological indicators appeared in each ranking.  RelTemp ranked first in 13 and 18 prefectures for the <65- and ≥65-year age groups, respectively. The meteorological indicators ranking first in the other prefectures varied.

Conclusions: RelTemp is the most important meteorological factor for heatstroke mortality in many prefectures; hence, RelTemp could be adopted as an auxiliary indicator for the “Heatstroke Alert”.

How to cite: Oka, K., He, J., Phung, V. L. H., Honda, Y., Hashizume, M., and Hijioka, Y.: Analysis of important meteorological indicators of heatstroke mortality in Japan, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-163, https://doi.org/10.5194/icuc12-163, 2025.

With rising urban temperatures, understanding thermal comfort variations among different demographic groups is critical for creating inclusive and thermally resilient outdoor spaces. This study investigates the thermal perception and adaptive behaviors of adults and children in urban parks within a hot-humid climate. Field measurements and surveys were conducted in four urban parks in Tainan, Taiwan, from July 2023 to May 2024. A total of 39 field campaigns were carried out, with 567 adult and 375 child participants.  Environmental monitoring was performed at multiple heights, including 80 cm—representing a child’s stature—to assess variations in microclimatic conditions experienced by different age groups. Key recorded parameters included air temperature, humidity, and black globe temperature, along with personal factors such as clothing insulation, height, weight, age, and activity levels. Surveys collected data on thermal sensation, perspiration, and behavioral adaptations to heat.

A novel aspect of this study is the incorporation of clothing and metabolic rate as dynamic variables in thermal comfort calculations, rather than relying on fixed values. The findings highlight distinct differences in thermal perception and adaptive behaviors between adults and children, emphasizing the need for age-inclusive urban park design. This study provides designers with valuable references for creating thermally comfortable public spaces, reflecting the actual thermal comfort of people engaging in recreational activities in urban parks.

How to cite: Yang, S.-R.: Thermal Comfort Differences Between Adults and Children in Hot and Humid Region, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-370, https://doi.org/10.5194/icuc12-370, 2025.

Urban heat islands, combined with extreme heat waves, can pose a public health risk. During the 2003 heat wave in Paris, strong correlations were observed between nighttime outdoor air temperatures and mortality [1]. However, previous studies only focus on outdoor nighttime air temperatures when citizens are sleeping, without linking these observations with the heat stress they may have been exposed to during the day or in their apartment. Similarly, studies [2] highlight the relationship between air temperature and mortality during heat waves at the city level. Building on this, we aim to demonstrate the viability of using heat stress as a metric to assess its impact on individual physiological responses.

This is one of the principals aims of the “Heat waves, urban Health islands, Health: a mobile sensing approach” (H3Sensing ANR research) project. Citizen science methods will be used in order to measure heat stress exposure over several days as well as individual physiological responses. Mobile measurements of microclimatic parameters [3] allow us to characterize and map heat stress exposure [4] in Greater Paris. Stationary measurements in apartments and individual surveys will complete the data set and combined with measured physiological data.

Beginning in March, 2025, the citizen science study will last for two periods of 4 days in spring and in summer with a target group of 180 Paris inhabitants. The proposed communication will present the study methodology in terms of measurement device prototyping and data processing as well as preliminary analyses from the study.

How to cite: Kamara, J., Hendel, M., Filaine, F., Grados, A., Chaix, B., Bigorgne, J., and Royon, L.: Monitoring pedestrian heat stress in Greater Paris, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-913, https://doi.org/10.5194/icuc12-913, 2025.