Help Privacy Policy Disclaimer
  Advanced SearchBrowse




Journal Article

Investigating the Urban Air Quality Effects of Cool Walls and Cool Roofs in Southern California


Tao,  Wei
Multiphase Chemistry, Max Planck Institute for Chemistry, Max Planck Society;

External Resource
No external resources are shared
Fulltext (restricted access)
There are currently no full texts shared for your IP range.
Fulltext (public)
There are no public fulltexts stored in PuRe
Supplementary Material (public)
There is no public supplementary material available

Zhang, J., Li, Y., Tao, W., Liu, J., Levinson, R., Mohegh, A., et al. (2019). Investigating the Urban Air Quality Effects of Cool Walls and Cool Roofs in Southern California. Environmental Science & Technology, 53(13), 7532-7542. doi:10.1021/acs.est.9b00626.

Cite as: https://hdl.handle.net/21.11116/0000-0004-CA72-8
Solar reflective cool roofs and walls can be used to mitigate the urban heat island effect. While many past studies have investigated the climate impacts of adopting cool surfaces, few studies have investigated their effects on air pollution, especially on particulate matter (PM). This research for the first time investigates the influence of widespread deployment of cool walls on urban air pollutant concentrations, and systematically compares cool wall to cool roof effects. Simulations using a coupled meteorology-chemistry model (WRF-Chem) for a representative summertime period show that cool walls and roofs can reduce urban air temperatures, wind speeds, and planetary boundary heights in the Los Angeles Basin. Consequently, increasing wall (roof) albedo by 0.80, an upper bound scenario, leads to maximum daily 8-h average ozone concentration reductions of 0.35 (0.83) ppbv in Los Angeles County. However, cool walls (roofs) increase daily average PM2.5 concentrations by 0.62 (0.85) μg m–3. We investigate the competing processes driving changes in concentrations of speciated PM2.5. Increases in primary PM (elemental carbon and primary organic aerosols) concentrations can be attributed to reductions in ventilation of the Los Angeles Basin. Increases in concentrations of semivolatile species (e.g., nitrate) are mainly driven by increases in gas-to-particle conversion due to reduced atmospheric temperatures.