A major challenge that has faced the climate movement to date is the simple fact that our greatest atmospheric adversary is colorless, odorless and shapeless. As climate scientist James Hansen once said, "If CO2 were purple we would all be running for the hills."

Though there have been thousands of peer-reviewed academic reports that all corroborate the basic facts around CO2 emissions and climate change, the public remains more or less befuddled by CO2. You can't visualize carbon jargon and, according to the newly published book, Climate Cover-Up, this is a weakness that climate skeptics and oily politicians have done a great job of exploiting.

Now two traveling art projects hope to help out, and they take two very different shapes, literally. One is a cube and one is a sphere.

After having written for years on carbon footprints and CO2 impacts, it was refreshing to SEE for the first time what a single tonne* of CO2 actually looks like. The Danish Climate & Energy Ministry created an installation called "1 Tonne" which replicates the equivalent volume of CO2 by filling a giant orange Planet Earth with helium (roughly 24' in diameter). Danes emit about eight such spheres per year.

Back in the States where we have a significantly larger impact (19.5 tonnes per year), a rather different approach was taken. The Carbon Cube, a project of the nonprofit Climate Changes Art, is a 6' x 6' x 6' unit that anyone can make using fabric or cardboard. That volume is the equivalent to about 20 pounds of CO2, roughly the emissions from using a single gallon of gasoline. The average American produces six cubes worth of CO2 every day (2,190 per year), which adds up (according to my algebra) to one giant 13 x 13 x 13 cube (78' cubed).

The individual cubes are hand-painted and have traveled to dozens of conferences around the world, making a colorful statement about the importance of accounting for our own personal carbon emissions. 

Both the cube and sphere will be featured at the upcoming U.N. Climate Conference in Copenhagen. The website has an open invitation for schools and communities to make their own cubes and submit them to the online gallery. Check out the cubes from China for a little inspiration.

*NB: 1 tonne refers to a metric ton, which is 1.1 American tons.

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