 It's to buy humanity time in the short term. We may have to settle for a more modest proposal, such as a carbon tax. Concept is simple. Put a price on pollution under a carbon tax system. A business would pay, for example, twenty dollars for every metric ton of carbon that they spew into the air. As of 2013, 33 countries and 18 smaller jurisdictions around the world have already put some sort of a price on carbon.