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Title: The surface urban heat island response to urban expansion: A panel analysis for the conterminous United States

Abstract

Abstract: Urban heat island (UHI), a major concern worldwide, affects human health and energy use. With current and anticipated rapid urbanization, improved understanding of the response of UHI to urbanization is important for impact analysis and developing effective adaptation measures and mitigation strategies. Current studies mainly focus on a single or a few big cities and knowledge on the response of UHI to urbanization for large areas is very limited. Modelling UHI caused by urbanization for large areas that encompass multiple metropolitans remains a major scientific challenge/opportunity. As a major indicator of urbanization, urban area size lends itself well for representation in prognostic models to investigate the impacts of urbanization on UHI and the related socioeconomic and environmental effects. However, we have little knowledge on how UHI responds to the increase of urban area size, namely urban expansion, and its spatial and temporal variation over large areas. In this study, we investigated the relationship between surface UHI (SUHI) and urban area size in the climate and ecological context, and its spatial and temporal variations, based on a panel analysis of about 5000 urban areas of 10 km2 or larger, in the conterminous U.S. We found statistically significant positive relationship betweenmore » SUHI and urban area size, and doubling the urban area size led to a SUHI increase of higher than 0.7 °C. The response of SUHI to the increase of urban area size shows spatial and temporal variations, with stronger SUHI increase in the Northern region of U.S., and during daytime and summer. Urban area size alone can explain as much as 87% of the variance of SUHI among cities studied, but with large spatial and temporal variations. Urban area size shows higher association with SUHI in regions where the thermal characteristics of land cover surrounding the urban are more homogeneous, such as in Eastern U.S., and in the summer months. This study provides a practical approach for large-scale assessment and modeling of the impact of urbanization on SUHI, both spatially and temporally, for developing mitigation/adaptation measures, especially in anticipated warmer climate conditions for the rest of this century.« less

Authors:
; ORCiD logo; ; ; ORCiD logo
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1368116
Report Number(s):
PNNL-SA-126569
Journal ID: ISSN 0048-9697; KP1703030
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Science of the Total Environment; Journal Volume: 605-606; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
urbanization; land surface temperature; urban expansion; spatiotemporal variation; urban area

Citation Formats

Li, Xiaoma, Zhou, Yuyu, Asrar, Ghassem R., Imhoff, Marc, and Li, Xuecao. The surface urban heat island response to urban expansion: A panel analysis for the conterminous United States. United States: N. p., 2017. Web. doi:10.1016/j.scitotenv.2017.06.229.
Li, Xiaoma, Zhou, Yuyu, Asrar, Ghassem R., Imhoff, Marc, & Li, Xuecao. The surface urban heat island response to urban expansion: A panel analysis for the conterminous United States. United States. doi:10.1016/j.scitotenv.2017.06.229.
Li, Xiaoma, Zhou, Yuyu, Asrar, Ghassem R., Imhoff, Marc, and Li, Xuecao. 2017. "The surface urban heat island response to urban expansion: A panel analysis for the conterminous United States". United States. doi:10.1016/j.scitotenv.2017.06.229.
@article{osti_1368116,
title = {The surface urban heat island response to urban expansion: A panel analysis for the conterminous United States},
author = {Li, Xiaoma and Zhou, Yuyu and Asrar, Ghassem R. and Imhoff, Marc and Li, Xuecao},
abstractNote = {Abstract: Urban heat island (UHI), a major concern worldwide, affects human health and energy use. With current and anticipated rapid urbanization, improved understanding of the response of UHI to urbanization is important for impact analysis and developing effective adaptation measures and mitigation strategies. Current studies mainly focus on a single or a few big cities and knowledge on the response of UHI to urbanization for large areas is very limited. Modelling UHI caused by urbanization for large areas that encompass multiple metropolitans remains a major scientific challenge/opportunity. As a major indicator of urbanization, urban area size lends itself well for representation in prognostic models to investigate the impacts of urbanization on UHI and the related socioeconomic and environmental effects. However, we have little knowledge on how UHI responds to the increase of urban area size, namely urban expansion, and its spatial and temporal variation over large areas. In this study, we investigated the relationship between surface UHI (SUHI) and urban area size in the climate and ecological context, and its spatial and temporal variations, based on a panel analysis of about 5000 urban areas of 10 km2 or larger, in the conterminous U.S. We found statistically significant positive relationship between SUHI and urban area size, and doubling the urban area size led to a SUHI increase of higher than 0.7 °C. The response of SUHI to the increase of urban area size shows spatial and temporal variations, with stronger SUHI increase in the Northern region of U.S., and during daytime and summer. Urban area size alone can explain as much as 87% of the variance of SUHI among cities studied, but with large spatial and temporal variations. Urban area size shows higher association with SUHI in regions where the thermal characteristics of land cover surrounding the urban are more homogeneous, such as in Eastern U.S., and in the summer months. This study provides a practical approach for large-scale assessment and modeling of the impact of urbanization on SUHI, both spatially and temporally, for developing mitigation/adaptation measures, especially in anticipated warmer climate conditions for the rest of this century.},
doi = {10.1016/j.scitotenv.2017.06.229},
journal = {Science of the Total Environment},
number = C,
volume = 605-606,
place = {United States},
year = 2017,
month =
}
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