This research aims to model urban heat islands in Natal, located on the coast of northeast Brazil, and to relate their spatial distribution to social vulnerability. Natal has a population of 750,000. The modeling of its urban heat islands was conducted using a database of thirty days of field data collected with fifteen thermometers. The Local Climate Zones (LCZ) of the study area were delineated using the R package LCZ4r. After delineating the LCZs, the temperature data were interpolated. Social vulnerability levels were calculated based on social data collected in the most recent national census, at the census tract level. Eight social variables were used to compose the index, covering income, education, age, and race. Each census tract in the city was classified by its level of social vulnerability on a scale from one (slightly socially vulnerable) to ten (highly socially vulnerable). The temperature data were then overlaid with the social vulnerability data. In the most socially vulnerable regions, there are few green spaces, the areas are more densely occupied, and urban structures such as parks and squares are rarely present, leading to higher temperatures. In areas with lower social vulnerability, the roads are wider, the blocks are less densely occupied, and green spaces are more prevalent, contributing to cooler temperatures. Furthermore, in the most socially vulnerable areas, the population's capacity to adapt to extreme temperature events is considered lower, making these areas more urgent for the implementation of public policies. This study aims to contribute to the discussion on Urban Climate Justice and to support the implementation of effective urban policies, particularly in the Global South, which faces significant climate and social challenges.

How to cite: Castelhano, F., Campos Neto, A., Cabral, I. J., and Anjos, M. W.: Urban Heat Islands and Social Vulnerability in a Large City in Northeastern Brazil, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-88, https://doi.org/10.5194/icuc12-88, 2025.

This work aims to develop a spatially explicit heat risk map for the city of São Paulo, at the census tract scale, based on open and public data and expert opinions. The methodological framework followed the IPCC’s definition of risk – as a function of hazard, vulnerability and exposure – and includes climate and environmental, and socio-economic parameters, weighted by expert opinions using the AHP method. The results show a strong relation between the heat risk and socio-economic factors, represented by the determinants of vulnerability and exposure. Initially, most of the tracts classified as ‘high’ or ‘extremely high risk’ are placed in affluent – due to the greater concentration of elderly – and in peripherical areas – due to low income, poor housing conditions and high population density. However, when the adaptation capacity is considered, people living in peripherical areas are subject to the highest levels of risk, while those in affluent areas can cope with the heat. This depicts the impact of social inequality and the improvement of social and economic conditions of people as the best path towards climate adaptation, as well as developing integrated policies aimed at reducing the risk and coping with it. Although other heat risk indexes have been already developed for São Paulo, the novelty is the use of detailed classification of heat hazard based on vegetation proximity, urban morphology, soil moisture, building mass, and housing type. This work also helps to fill the gap of heat risk research for subtropical cities. Finally, the methodology developed can be replicated to other cities in Brazil.

How to cite: Sobhie Muñoz, L., Duarte, D., and Emmanuel, R.: Heat risk in the city of São Paulo: A portrait of environmental and socioeconomic inequalities, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-302, https://doi.org/10.5194/icuc12-302, 2025.

Despite its mild winters, Portugal experiences the highest number of winter-related injuries and deaths. This suggests that inadequate housing and insufficient adaptive measures are major contributors to excess mortality.  

A 2021 study on elderly vulnerability to summer temperatures in Lisbon highlighted structural and behavioural limitations to adaptive capacity. However, the relationship between indoor thermal environments and human health in disadvantaged communities remains underexplored.  

This observational study was conducted in a low-income, informally constructed neighbourhood where residents face poverty and significant health challenges. During winter, meteorological data were collected from six households, monitoring thermal conditions in the most frequently used spaces: the bedroom and living room. Biometeorological indices, such as the Universal Thermal Climate Index (UTCI) and Predicted Mean Vote (PMV), were used to assess cold exposure, and face-to-face interviews provided further insight into living conditions.  

The results revealed severe indoor cold exposure, with a significant portion of monitored hours falling below thermal comfort guidelines, particularly at night. Indoor temperatures frequently dropped to levels that worsened respiratory issues, joint pain, and mobility difficulties. Although most households owned heating devices, high energy costs meant they were only used on cold days. Instead, residents resorted to inadequate measures such as blankets or going to bed early to escape the cold.  

Health impacts were evident, with residents reporting aggravated bone pain, throat irritation, sleep disturbances, and respiratory illnesses linked to high humidity and mould exposure. Additionally, a lack of knowledge on indoor thermal adaptation was observed, highlighting the need for greater community education and awareness initiatives.  

This study provides critical insights into the barriers to thermal adaptation in vulnerable communities. It reinforces the urgent need for equitable housing policies and climate justice-driven interventions to improve living conditions and access to affordable energy.

How to cite: Vasconcelos, J., Conceição, C., and Fragoso, M.: Indoor Thermal Vulnerability and Climate Justice: Understanding Adaptation Barriers in a Low-Income Lisbon Neighbourhood, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-736, https://doi.org/10.5194/icuc12-736, 2025.

This study employs mixed methods involving geospatial and sensor technologies and quantitative data analysis to investigate the relationship between housing characteristics, heat perception, and self-reported health outcomes in an informal neighborhood in Dar es Salaam at both community and building scales.

We used a mixed-method approach, including a webGIS-based questionnaire administered during the hot season (December 2023 to February 2024). The questionnaire covered socio-demographic factors, heat perception, health outcomes, and housing characteristics. Concurrently, we collected heat index data in indoor spaces of 18 houses and one outdoor monitoring site using Kestrel heat stress monitors. Statistical analyses, including clustering, descriptive statistics, and ANOVA, were conducted on quantitative and qualitative datasets to establish relationships between housing characteristics, subjective and objective heat perception/exposure, and self-reported outcomes at building and community scales.

Heat monitoring data analysis revealed significant heat stress levels regardless of space and period. Outdoors, 60-70% of daytime and 5-25% of nighttime periods were categorized as "Hot" to "Extremely Hot." Indoors, 60-70% of daytime and 55-65% of nighttime periods were similarly categorized, regardless of housing typologies/material combinations. This persistent diurnal heat exposure resulted in adverse health outcomes such as muscle cramps, headaches, malaria, dizziness, and tiredness among others, as identified within the neighbourhood. Qualitative data analysis at the community level indicated distinct differences in housing characteristics and heat perception, emphasizing the importance of building-scale grey adaptation. The findings highlight housing conditions that limit residents' capacity to adapt to heat-related problems.

This study provides local evidence regarding the interrelationship between heat, housing, and the built environment. The data reveal disparities in heat perception and exposure in indoor spaces based on housing characteristics, underscoring the widespread housing-related vulnerability to heat stress.

How to cite: Morakinyo, T. E., Mbuya, E., Mngumi, L., and Obe, B.: The Nexus of Heat, Housing, and Health in Informal Settlements in Dar es Salaam, Tanzania, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-987, https://doi.org/10.5194/icuc12-987, 2025.

Long term adaptation plans to climate change are affected by uncertainties over where climate hazards, including heat waves, cloudbursts, hurricanes and other storms, might occur and the shifting location of vulnerable populations to these events.   To address this dilemma, this research examines whether changes occurring in urban neighborhoods are affecting an important component of vulnerability, climate sensitivity and how these changes affect exposure to heat.  We analyze the shifts in climate sensitive of communities and associate these changes with neighborhood change and land surface temperature using New York City as a case study.  With Census tract as the neighborhood unit, we deploy Self-Organizing Maps (SOM) to identify the shifts in community climate sensitive and the changes in neighborhood type from 1990 to 2020.  Our results suggest that the number of communities defined as climate-sensitive increased from 1,113 to 1,179 (approximately 6% increase) during the study period.  Logistic regression of nominal change in climate sensitivity suggests differences in the probabilities of change by neighborhood type and intensity of change.  We also find that shifting climate sensitivity and neighborhood types are associated with land surface temperature changes.  For example, neighborhoods that shift from non-sensitive to sensitive populations are associated with higher rates of increase in land surface temperature than areas that shift from sensitive to non-sensitive communities.  These findings suggest changes in climate sensitivity are associated with types of neighborhoods and increases in land surface temperature, highlighting issues of climate justice for marginalized communities.

How to cite: Marcotullio, P. J., Safin, E., and Fouad, G.: Shifting climate sensitivity and differential exposure to heat in NYC 1990 - 2020 , 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-1141, https://doi.org/10.5194/icuc12-1141, 2025.

Heatwaves pose a growing threat to urban populations, disproportionately impacting vulnerable groups such as the elderly, low-income residents, and those in inadequate housing. While cooling shelters serve as a key adaptation measure, their spatial distribution and qualitative accessibility remain understudied. This study evaluates the spatial equity of cooling shelters in Seoul, South Korea, using the Gini coefficient to assess not only the number of shelters per administrative unit but also their usability factors, including nighttime and holiday access, cooling capacity, and accommodation availability. The Heat Vulnerability Index (HVI) was developed at the neighborhood level, incorporating environmental, demographic, and socioeconomic factors to quantify exposure and sensitivity to heat risks. The spatial inequality of cooling shelter accessibility was then examined through heatmaps and the Gini coefficient, comparing shelter distribution with vulnerability patterns. The results reveal that high-risk areas often have fewer cooling shelters and reduced accessibility, limiting their effectiveness as adaptation measures. The analysis suggests that current cooling center policies fail to fully account for the needs of vulnerable populations, particularly in areas with limited shelter accessibility during critical periods. These findings underscore the necessity of integrating qualitative shelter characteristics into policy frameworks to ensure equitable adaptation strategies. By addressing both the quantity and usability of cooling shelters, urban resilience can be strengthened, particularly for the most heat-vulnerable communities. This study provides a methodological approach for assessing climate adaptation policies and highlights the importance of spatial equity in urban heatwave mitigation efforts.

How to cite: Kim, S., Park, C., and Lee, D.: Assessing Spatial Equity in Anticipatory Adaptation: The Case of Cooling Centers in Seoul, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-999, https://doi.org/10.5194/icuc12-999, 2025.

The interplay of climate change and urbanization has led to uneven heat exposure patterns, disproportionately impacting marginalized communities and raising critical concerns about environmental justice. While studies primarily in the United States highlight the heightened heat vulnerability of low-income and ethnic minority groups, similar analyses are still lacking for other countries, creating a significant gap in understanding global environmental inequities. This gap limits assessment of socio-economic and ethnic disparities to identify shortcomings in urban planning strategies.

This study aims to integrate social and environmental sciences to address environmental injustice by investigating the relationship between extreme heat exposure and socio-economic disparities across municipalities or counties for various countries including Australia, New Zealand, Canada, Germany, and the U.K. The research leverages satellite-derived land surface temperature data at daytime and nighttime for summer and census datasets from countries to examine key socio-economic indicators, such as education levels, age distribution, and the proportion of foreign-born populations. Additionally, the study delves into urban planning parameters including green spaces, building density and local climate zones to assess their correlation with land surface temperatures, and also air temperature and heat stress indices for the case of Germany.

The findings reveal varying levels of heat exposure disparities across countries and its severe consequences for vulnerable populations, emphasizing the urgent need for equitable urban planning. This research calls on policymakers and urban planners to address environmental injustices by prioritizing inclusive interventions aimed at mitigating socio-economic and racial disparities in urban heat exposure. Furthermore, the study serves as a framework for conducting similar analysis worldwide, supporting the development of equitable and sustainable urban environments.

How to cite: Chawla, J., keller, P., Varma, V., and Benz, S.: Examining Race and Class Disparities in Urban Heat: Towards Environmental Justice in Urban Planning, 12th International Conference on Urban Climate, Rotterdam, The Netherlands, 7–11 Jul 2025, ICUC12-264, https://doi.org/10.5194/icuc12-264, 2025.