A study carried out by the University of Granada (UGR) and the Federal University of Rio de Janeiro has mapped the areas in Granada that are most vulnerable to extreme heat, promoting mitigation strategies based on green infrastructure and social criteria
A recent study by UGR researchers and the Federal University of Rio de Janeiro has mapped the heat-risk areas of Granada and its metropolitan area, analysing how the distribution of green spaces can help mitigate the urban heat island (UHI) effect. Given that urban environments are increasingly vulnerable to climate change, understanding this dynamic is essential for designing effective mitigation and adaptation strategies based on scientific evidence.
The study utilised the InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) model, a free and open-source tool used to map and value ecosystem services. The researchers integrated high-resolution biophysical and social information from multiple networks and sources (REDIAM, SIPNA, PNOA, GEE, IECA and INE). Key variables such as land surface and air temperature, evapotranspiration, vegetation cover and the distribution of buildings were obtained from satellite images and existing climate data. This enabled accurate simulations of urban heat exposure, giving rise to the identification of the most affected hotspots in the city of Granada. Statistical tools were also used to analyse how different vegetation patterns influence heat mitigation, identifying the most effective elements of green infrastructure.
To address social vulnerability, the researchers spatially analysed demographic indicators from official statistics to identify the groups that are most exposed during extreme heat events. They focused on aspects such as the number of available medical centres, household income, the proportion of people over 65, households living below the 60% poverty threshold, and population density. By combining this information into a social vulnerability index and comparing it with the heat exposure index, the study identified priority zones where high levels of climate risk and social vulnerability coincide. Specifically, four priority zones were identified for the development of heat mitigation strategies: three within the city of Granada (parts of the southern Zaidín district and northern La Chana district, and the city centre) and one in the metropolitan area (the northern part of the adjacent city of Armilla).
According to the results, urban areas with more than 35% of their surface covered by vegetation and mean green patches exceeding 200 m² experience a significant reduction in temperatures. In densely populated areas, where the creation of large green spaces is not a viable option, the study proposes connecting smaller green infrastructures to enhance their cooling effect, highlighting the need for strategic urban planning.
The research team is currently analysing the effectiveness of various tree species in mitigating extreme temperatures, with the aim of identifying those capable of generating a more favourable microclimate and prioritising their use in the design of urban green spaces. In addition to mitigating the heat island effect, the BioCiTrees project, led by researcher Nuria Pistón, together with Professor Regino Zamora, is also studying the ability of trees to filter air pollutants and promote biodiversity in urban environments. The findings of this project are expected to provide urban policymakers with a set of guidelines based on ecological and social criteria for the design of more efficient and equitable green infrastructure.
Sources:
- Article published in the scientific journal Urban Forestry & Urban Greening: https://doi.org/10.1016/j.ufug.2025.128794
- BioCiTrees project website
- Related news: http://sl.ugr.es/0eEC
Contact details:
Nuria Pistón Caballero: nuriapiston@ugr.es
Regino Zamora: rzamora@ugr.es
Department of EcologyAndalusian Inter-University Institute for Earth System Research (IISTA-CEAMA)
Translated version: This text has been translated into English by the Language Services Unit (Vice-Rectorate for Internationalization) of the University of Granada.
