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Title: Comparing land surface temperature and mean radiant temperature for urban heat mapping in Philadelphia
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.  more » « less
Award ID(s):
2314709
PAR ID:
10519800
Author(s) / Creator(s):
; ;
Publisher / Repository:
Elsvier
Date Published:
Journal Name:
Urban Climate
Volume:
51
Issue:
C
ISSN:
2212-0955
Page Range / eLocation ID:
101615
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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