The "trees" look like goal posts with Venetian blinds, and are a bit smaller than a small windmill. They essentially act as atmosphere scrubbers. The slats would be covered with an absorbent coating, such as limewater, which could be removed and then buried.

In a National Public Radio interview, Lackner says one large unit could capture 90,000 tons of carbon dioxide from 15,000 cars or all the CO2 emitted from 4,000 people. You would need 250,000 units to capture the world's carbon dioxide.

Tucscon, Ariz. firm, Global Research Technologies, has built a 9-foot-high prototype of the tree.

Many ifs are involved for this to work as planned. It sounds a bit farfetched and carbon sequestration is still an expensive endeavor, but this could be an interesting and apparently effective solution if storage costs do decrease and if geological storage is safe and permanent – a claim that many still doubt. At the very least, it is much needed research into carbon capture and sequestration.