Evidence for urban heat island reduction through forestation across multiple regions

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides a meta-analytic estimate of urban forestation's cooling effect (0.06°C per 1% increase) and identifies gaps in integrating climate change and justice.

🏢実務担当者:Offers quantitative evidence to justify urban greening investments for heat mitigation, useful for corporate adaptation planning and green infrastructure projects.

🏛政策担当者:Supports urban forestry policies with empirical effect sizes, highlighting the need to consider climate justice to avoid unintended social consequences.

Urban growth contributes to urban heat islands (UHIs), disproportionately impacting low-income communities as climate change advances. In response, green infrastructure has emerged as a promising nature-based solution. Urban forests, in particular, offer multiple co-benefits, including biodiversity conservation and increased climate resilience. However, the ability of urban forests in mitigating UHIs still needs to be comprehensively evaluated. This systematic review assesses the effectiveness of forestation—reforestation and afforestation—in mitigating UHIs globally. It also examines the extent to which the existing literature integrates climate change and climate justice into UHI studies. A search of the Web of Science and Scopus databases retrieved 1,361 papers, of which 21 focused on the empirical effects of forestation on UHIs mitigation, yielding 132 case studies. Most were either empirical or modeling studies investigating the effects of forestation on daytime heat islands during the summer, mainly focusing on surface temperature. Our findings suggest that, in urban areas, a 1% increase in forested area is associated with a reduction of approximately 0.06°C in mean surface temperature. This result should be interpreted with caution, however, as the effect varies across environmental contexts, and is stronger in drier environments. Moreover, the statistical models show only modest explanatory power, underscoring the need for further studies to better understand its drivers. Only five papers of 21 studies addressed aspects of climate injustice, and just one considered climate change scenarios. None simultaneously considered UHI mitigation, climate justice, and climate change. These results show the strong potential of forestation as a strategy to mitigate UHIs and the need to integrate climate justice into planning to ensure that forestation efforts do not inadvertently create new social or environmental problems.

• openalex https://doi.org/10.3389/frsus.2026.1744061first seen 2026-07-25 04:59:00