White Roofs Don't Slow Global Warming, Says New Study

A recent study published by researchers at Stanford University shows how the heat island effect has little bearing on global warming and how painting roofs white actually may increase temperatures, writes David Malakoff for The Guardian.

The two researchers, Mark Z. Jacobson and John E. Ten Hoeve, developed a model that "meshed data on land use, vegetation, albedo (the reflective capacity of different land uses) and soil-type. Then, they ran two 20-year-long simulations to see how much heat islands contributed to "gross global warming" (warming before cooling factors) – and what impact a lot of white paint might have."

In the end, the study showed how the urban heat island effect may only contribute 2-4 percent of gross global warming.

White Roofs on the other hand could actually warm the Earth on a global scale. "Although white surfaces are cooler, the increased sunlight they reflect back into the atmosphere by can increase absorption of light by dark pollutants such as black carbon, which increases heating."

Full Story: White roofs are not a global warming silver bullet, study finds


Brand new! Urban Grid City Collection

Each city has its own unique story. Commemorate where you came from or where you want to go.
Grids and Guide Red book cover

Grids & Guides

A notebook for visual thinkers. Available in red and black.
Planetizen Courses image ad

Planetizen Courses

Advance your career with subscription-based online courses tailored to the urban planning professional.
Starting at $16.95 a month
T-shirt with map of Chicago

Show your city pride

Men's Ultrasoft CityFabric© tees. Six cities available.