Incentivize the Albedo Effect

A low-cost tool to help combat global warming: get local governments, non-profits, and community organizations to incentivize homeowners, building owners, and others to paint rooftops and other surfaces white or with a highly reflective coating. The more solar radiation is reflected from the earth, the less global warming occurs.

by Cameron Tinsler on June 17th, 2014, 9:16 pm PDT. This Ivia has been viewed 5,226 times. Last improved on August 27th, 2014, 4:11 am PDT.

The amount of energy reflected by a surface is determined by the reflectivity of that surface, called the albedo. A high albedo means the surface reflects the majority of the radiation hitting it and absorbs the rest. A low albedo means a surface reflects a small amount of the incoming radiation and absorbs the rest.  Fresh snow, for example, reflects up to 95% of the incoming radiation.  At the other end of the spectrum, a freshly blacktopped parking lot absorbs a tremendous amount of the sun's energy--if you've ever tried to walk barefoot across blacktop on a summer day, you get the idea.

State and local governments, non-profits, community organizations and other groups should incentivize home and building owners, car owners, and transportation departments to switch from from high albedo surfaces to low ones.  Encourage building owners using tar and gravel roofs to use a light-colored gravel.  Encourage homeowners to paint their homes in pastels.  Use light colored sand or gravel blends for median strips and playgrounds.  Use whiter blends of cement and concrete for roads, sidewalks, and parking lots.

Mankind has used this effect to cool towns and neighborhoods for thousands of years.  To this day buildings from South Florida to the Mediterranean use lighter colors to keep cool.  In California most UPS delivery trucks and school buses have white roofs to keep out the heat.  

What if most cars had white roofs?  What if most houses had white roofs ( and solar panels)?  What if most streets and highways increased their reflectivity by a significant amount?  The aggregate impact would be substantial.

Vote for 10 this Ivia

About the Author

Cameron Tinsler
Novato, California, United States

Contribute to this Ivia!


Reed W. Solomon 3 years ago

One thing I think would be cool is a way of measuring the energy reflection percentage, and categorizing common building materials and paints. Obviously lighter is better, and the basics are shown above, but more data would make for easier decisions.
I love the image, btw.

Cameron Tinsler 3 years ago

Yes, if makers of exterior paints, for example, put an albedo number on the can it would be helpful to concerned buyers. Or stores themselves could include albido info on the shelves.

Also, just for comfort, I would like to see parking lot blacktop replaced with a light gray top. Pitch black lots heat up fast, and can be pretty uncomfortable to walk across on warm, sunny days.

Zachary Adam Zell 3 years ago

Is it known what solar panels reflect? Also if the surrounding area of a roof is a lighter color does a solar panel somehow receive more solar radiation due to a more concentrated surface?

Edited 3 years ago


Cameron Tinsler 3 years ago

Was unable to add an image to this Ivea. Wanted to use this:

Christian P Hupfeld 3 years ago

Were you trying to add this within the body of the Ivia or as the main image? Currently, there is no support for uploading an image by URL for the main image. You would need to download it to your computer then upload it to the Ivia. Adding images from a link is a planned enhancement for the main image.

Cameron Tinsler 3 years ago

Hi Christian, yes, it was by downloading the image to my desktop first, then uploading. Thanks for placing it.