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Many cities are experiencing more frequent extreme heat during hot summers. With the rise of global temperature, the thermal comfort in urban areas become even worse. Quantitative information of the spatial distributions of urban heat has become increasingly important for resilience and adaptation to climate change in cities. This study compares satellite-derived land surface temperature (LST) and urban microclimate modeling-based mean radiant temperature (Tmrt) for mapping the urban heat distributions in Philadelphia, Pennsylvania, USA. The LST was estimated based on Landsat 8 thermal imagery with a spatial resolution of around 100 m, while the Tmrt was simulated based on high resolution LiDAR and national aerial imagery program multispectral aerial imageries with a spatial resolution of 1 m. Result shows that both LST and Tmrt show a similar general pattern of the urban heat across the study area, while the Tmrt presents much more details of the heat variations street by street and neighborhood by neighborhood. The LST tends to have a stronger relationship with the Tmrt on building roofs, which are usually not the place for human activities. This studyprovides evidence for choosing more appropriate metrics in urban heat-related studies.
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Exploring a Just and Diverse Urban Forests’ Capacity for Mitigating Future Mean Radiant Temperatures
Abstract: The Pittsburgh Metropolitan Region in Western Pennsylvania, U.S., like many cities glob-ally, historically has an inequitably distributed urban forest and faced street tree biodiversity challenges. Additionally, Pittsburgh faces several barriers and threats to maintaining and expanding its urban tree cover, including pests, diseases, social acceptance, built environment obstacles, and climate change. To address these concerns, in 2012, Pittsburgh created an Urban Forest Master Plan setting equitable forest cover and biodiversity benchmarks. This paper documents the status of achieving these benchmarks and uses microclimate simulations to assess the capacity of these benchmarks in mitigating future mean radiant temperatures. Results demonstrate that the story of Pittsburgh’s urban forest cover, street tree biodiversity, and age diversity is complex, but inequities are primarily driven by income. However, if Pittsburgh can achieve its forest cover benchmarks, it can reduce its neighbourhoods’ 2050 mean radiant temperature below 2010 temperatures, even under climate change-fuelled extreme heat events. The process and results reported in this paper allow designers and decision-makers to calibrate localized urban forest benchmarks more effectively based on various future scenarios while ensuring the equitable distribution of heat mitigation.
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- Award ID(s):
- 1828822
- PAR ID:
- 10537970
- Publisher / Repository:
- Scopus
- Date Published:
- Journal Name:
- Journal of digital landscape architecture
- ISSN:
- 2367-4253
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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