TY - JOUR
T1 - Increasing Human-Perceived Heat Stress Risks Exacerbated by Urbanization in China
T2 - A Comparative Study Based on Multiple Metrics
AU - Luo, Ming
AU - Lau, Ngar Cheung
N1 - Funding Information:
This research is partially funded by the National Natural Science Foundation of China (41871029), the National Key R&D Program of China (2019YFC1510400), and the Science and Technology Program of Guangzhou, China (202102020489). The appointment of Ngar‐Cheung Lau at The Chinese University of Hong Kong is partially supported by the AXA Research Fund, and the appointment of Ming Luo at Sun Yat‐sen University is partially supported by the Pearl River Talent Recruitment Program of Guangdong Province, China (2017GC010634). The authors are greatly thankful to the anonymous reviewers for their constructive suggestions and comments that improve our paper.
Funding Information:
This research is partially funded by the National Natural Science Foundation of China (41871029), the National Key R&D Program of China (2019YFC1510400), and the Science and Technology Program of Guangzhou, China (202102020489). The appointment of Ngar-Cheung Lau at The Chinese University of Hong Kong is partially supported by the AXA Research Fund, and the appointment of Ming Luo at Sun Yat-sen University is partially supported by the Pearl River Talent Recruitment Program of Guangdong Province, China (2017GC010634). The authors are greatly thankful to the anonymous reviewers for their constructive suggestions and comments that improve our paper.
Publisher Copyright:
© 2021. The Authors. Earth's Future published by Wiley Periodicals LLC on behalf of American Geophysical Union.
PY - 2021/7
Y1 - 2021/7
N2 - More than half of the total population in China are living in cities. Especially, the people in highly developed and spatially integrated city clusters, i.e., urban agglomerations (UAs), are facing increasing human-perceived heat stress that describes the combined effects of hot temperature, high humidity, and lowered surface wind speed. By analyzing multiple indicators over 20 major UAs across China, we demonstrate that summer heat stress has been significantly intensifying in nearly all UAs during 1971–2014. This intensification is more profound in northern than southern regions and is especially stronger in more urbanized and densely populated areas (e.g., Beijing-Tianjin-Hebei and the Yangtze River Delta). Based on a dynamic classification of weather stations using time-varying land use/land cover maps, we find that urban core areas exhibit distinctly stronger increasing heat stress trends than their surrounding rural areas. On average, urbanization contributes to approximately one-quarter of the total increase in mean heat stress over urban core areas of UAs and nearly half of the total increase in extreme heat stress events. The urbanization effect is also dependent on the geographical region within China. Urbanization tends to have stronger intensifying effects on heat stress in UAs with higher population density in low-altitude areas, while it has a relatively weaker intensifying and even weakening effect in some arid and high-altitude regions. Moreover, as various heat stress metrics may yield different estimations of long-term trend and urbanization contribution, the particular choice of heat stress indicator is of critical importance for investigations on this subject matter.
AB - More than half of the total population in China are living in cities. Especially, the people in highly developed and spatially integrated city clusters, i.e., urban agglomerations (UAs), are facing increasing human-perceived heat stress that describes the combined effects of hot temperature, high humidity, and lowered surface wind speed. By analyzing multiple indicators over 20 major UAs across China, we demonstrate that summer heat stress has been significantly intensifying in nearly all UAs during 1971–2014. This intensification is more profound in northern than southern regions and is especially stronger in more urbanized and densely populated areas (e.g., Beijing-Tianjin-Hebei and the Yangtze River Delta). Based on a dynamic classification of weather stations using time-varying land use/land cover maps, we find that urban core areas exhibit distinctly stronger increasing heat stress trends than their surrounding rural areas. On average, urbanization contributes to approximately one-quarter of the total increase in mean heat stress over urban core areas of UAs and nearly half of the total increase in extreme heat stress events. The urbanization effect is also dependent on the geographical region within China. Urbanization tends to have stronger intensifying effects on heat stress in UAs with higher population density in low-altitude areas, while it has a relatively weaker intensifying and even weakening effect in some arid and high-altitude regions. Moreover, as various heat stress metrics may yield different estimations of long-term trend and urbanization contribution, the particular choice of heat stress indicator is of critical importance for investigations on this subject matter.
KW - apparent temperature
KW - climate change
KW - heat index | heat stress
KW - heatwave
KW - urban agglomerations in China
KW - urbanization effect | wet-bulb temperature
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UR - http://www.scopus.com/inward/citedby.url?scp=85109535292&partnerID=8YFLogxK
U2 - 10.1029/2020EF001848
DO - 10.1029/2020EF001848
M3 - Article
AN - SCOPUS:85109535292
SN - 2328-4277
VL - 9
JO - Earth's Future
JF - Earth's Future
IS - 7
M1 - e2020EF001848
ER -