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Title: Cool Roofs in Guangzhou, China: Outdoor Air Temperature Reductions during Heat Waves and Typical Summer Conditions

Journal Article · · Environmental Science and Technology
 [1];  [2];  [3];  [2];  [2]
  1. Chinese Academy of Sciences (CAS), Beijing (China). International Center for Climate and Environment Sciences and Inst. of Atmospheric Physics
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Heat Island Group
  3. Chinese Academy of Sciences (CAS), Beijing (China). International Center for Climate and Environment Sciences and Inst. of Atmospheric Physics; Nanjing Univ. of Information Science & Technology (NUIST)(China). Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters
+ Show Author Affiliations

In this work, we simulate temperature reductions during heat-wave events and during typical summer conditions from the installation of highly reflective "cool" roofs in the Chinese megacity of Guangzhou. We simulate temperature reductions during six of the strongest historical heat-wave events over the past decade, finding average urban midday temperature reductions of 1.2 °C. In comparison, we simulate 25 typical summer weeks between 2004 and 2008, finding average urban midday temperature reductions of 0.8 °C, indicating that air temperature sensitivity to urban albedo in Guangzhou varies with meteorological conditions. We find that roughly three-fourths of the variance in air temperature reductions across all episodes can be accounted for by a linear regression, including only three basic properties related to the meteorological conditions: mean daytime temperature, humidity, and ventilation to the greater Guangzhou urban area. While these results highlight the potential for cool roofs to mitigate peak temperatures during heat waves, the temperature reductions reported here are based on the upper bound case, which increases albedos of all roofs (but does not modify road albedo or wall albedo).

Research Organization:
Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Building Technologies Office; USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities Division; U.S.-China Clean Energy Research Center—Building Energy Efficiency Consortium (CERC-BEE); Chinese Academy of Sciences (CAS); National Natural Science Foundation of China (NSFC)
Grant/Contract Number:
AC02-05CH11231; XDA05110200; 41305093
OSTI ID:
1459361
Journal Information:
Environmental Science and Technology, Vol. 49, Issue 24; Related Information: © 2015 American Chemical Society.; ISSN 0013-936X
Publisher:
American Chemical Society (ACS)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 26 works
Citation information provided by
Web of Science

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