Comparing Urban Heat Exposure between Favelas and Public Housing with Open-Access Remote Sensing Data: A Case Study of Vila da Barca, Belém, Brazil
Research Poster Arts & Humanities 2025 Graduate ExhibitionPresentation by Lara Garcia
Exhibition Number 197
Abstract
Urban heat is a growing health concern, particularly for vulnerable populations in rapidly urbanizing areas. Conventional heat exposure assessments often rely on meteorological data and granular Geographic Information System (GIS) information describing buildings' heights, footprint areas, densities, streets' widths, and urban trees' canopy coverage. However, the lack of geospatial data at the street scale has historically rendered cities from the Global South without the means to execute comprehensive heat exposure and mean radiant temperature simulations. Recently developed open-access high-resolution, remote sensing global vegetation canopy and building height datasets can help bridge such a gap and inform a comprehensive heat exposure assessment for fast and informally growing cities such as Belém, Brazil. This study investigates the spatiotemporal dynamics of urban heat exposure in Belém, Brazil, by comparing mean radiant temperature estimates (Tmrt) between a closely sited favela (informal settlement) and the Vila da Barca public housing community. The study examines the impact of the two urban housing patterns on thermal comfort throughout 2020. Results suggest consistently higher Tmrt estimates in the public housing development area due to its low-rise, high-density configuration and higher predominance of heat-absorbent materials than the favela. This case study sheds light on whether relocating residents from favelas to public housing further exacerbates residents' urban heat exposure. This research also explores the possibilities and limitations of integrating open remote sensing canopy data and environmental simulations to advance more context-sensitive urban planning analyses and policies addressing heat-related risks in vulnerable communities.
Importance
This research integrates high-resolution remote sensing and machine learning-predicted global height datasets to examine differences in heat exposure between favelas and public housing developments. Belém was selected as a representative case due to its high frequency of annual heatwave events and rapid informal urban expansion in Brazil. Historically, little research has investigated extreme heat exposure in the Global South from a built environment perspective. This work addresses such knowledge and data coverage gaps by hypothesizing that public housing developments expose residents to higher urban heat exposure than favelas. Since public housing often comprises low-rise, high-density residential units with extensive use of heat-absorbent surface materials and scarce green open spaces, which ultimately exacerbates thermal discomfort and hampers residents' heat mitigation capacity.