Citation

Cao M, Rosado P, Lin Z, Levinson R, Millstein D. Environ. Sci. Technol. 2015; 49(24): 14672-14679.

Copyright

(Copyright © 2015, American Chemical Society)

DOI

10.1021/acs.est.5b04886

PMID

26523605

Abstract

In this paper 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, Guangzhou. We simulate temperature reductions during six of the strongest historical heat-waves 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 strongly based on 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 temperatures, 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 where all roofs are modified to be more reflective (but does not include changes to road or wall reflectivity).

Language: en