Climate Resolve

The Second Path: Addressing Climate Change by Enhancing Solar Reflection in Cities

Slowing climate change is our goal—and it can be achieved via two main strategies. We can either reduce the volume of greenhouse gasses (GHG) in the atmosphere or we can bounce bands of sunlight back into space.

The first path—reducing GHG—has been the overwhelming focus of governmental action. And appropriately so. For the past 170 years society has extracted trillions of tons of coal, oil, and gas, burned them, and lofted heat-capturing particles into the atmosphere. We made the problem and we can undo the damage.

The second path—reflecting sunlight—has been less explored. Neither the federal government nor the State of California is currently promoting solar-reflection as a means of curbing climate change. While Climate Resolve has won local advances on cool roofs and cool pavements, we did so mainly as a means of protecting communities from extreme heat.

Our rapidly expanding civilization has radically altered the earth’s solar energy budget. Society’s use of dark-pigmented materials converts sunlight into heat, much of which is then captured by greenhouse gases and re-radiated back to earth. (The main mechanism of climate change.) In California alone, where there was once grassland and chaparral, we’ve built hundreds of millions of lane miles of dark asphalt streets and millions more asphalt-shingled homes.

On June 30, over 125 people joined Climate Resolve on the Remo platform to learn about solar-reflective materials. Reflecting Sunlight: Albedo as a Means for Reducing the Greenhouse Effect featured four renowned scholars; Dr. Maria Hakuba (NASA Jet Propulsion Laboratory), Dr. Hashem Akbari (Concordia University), Dr. Hessam Azarijafari (Massachusetts Institute of Technology) and Dr. Ronnen Levinson (Lawrence Berkeley National Laboratory).

Ably led by energy and climate policy expert, Roel Hammerschlag, we learned that solar-reflective materials needn’t be white. They need only reflect the right bands of light so that they can evade the heat capturing GHG particles. And that there are solar-reflective products available today.

Special thanks to the sponsors of the workshop—ClimeCo, Latham & Watkins, GAF, Skanska, and the Adrienne Arsht-RockefellerFoundation Resilience Center—for making this exciting work possible.

And with your help, Climate Resolve will continue pursuing both paths, reducing GHG as well as advocating for new planet-cooling policies. Watch this space.

– Jonathan Parfrey

Climate Resolve