The researchers, including a Department of Energy scientist at Pacific Northwest National Laboratory, modified the land surface albedo in the Community Earth System Model (CESM) to represent the change induced by implementing bright roofs. The prognostic aerosol treatment in CESM allowed the researchers to consider the dampening effect of aerosols more realistically. To estimate the uncertainty of the climate impact, they performed long-term ensemble slab ocean model simulations. They found that the global adoption of bright roofs in urban areas would reduce urban heat islands everywhere, with an annual- and global-mean decrease from 1.6 to 1.2 K. Those decreases are statistically significant, except for some areas in Africa and Mexico where urban fraction is low, and some high-latitude areas during wintertime. Analysis of the surface and top of atmosphere energy budget in urban regions at continental-scale shows bright roofs cause increases in solar radiation leaving the Earth−atmosphere system in most regions around the globe, though the presence of aerosols and clouds are found to partially offset increases in upward radiation. Aerosols dampen bright roof-induced increases in upward solar radiation, ranging from 4% in the United States to 18% in more polluted China. Adoption of cool roofs also causes statistically significant reductions in surface air temperatures in urbanized regions of China and the United States. India and Europe show statistically insignificant changes in that regard. The research suggests that while bright roofs are an effective tool for reducing building energy use in hot climates, reducing urban heat islands, and regional air temperatures, their influence on the global climate is likely negligible.