These are heady times for the cannabis industry. Countries from Mexico to Norway are taking concrete steps towards decriminalizing the drug. The biggest prize of all is the American market, where cannabis is now broadly legal in 15 states, and analysts believe the dominoes will keep falling. With that liberalization of pot laws comes increased investment – but also a greater focus on the environmental cost of cultivation. Strict laws around growing cannabis leave the crop with a heavy carbon footprint. In Arizona, cannabis is believed to produce more carbon dioxide emissions than coal – and that state is one of the 10 largest coal producers in the U.S. In this week’s Riskin Report, CTV News Science and Technology Specialist Dan Riskin looks at what’s behind the heavy pollution price of pot, and what could be done to reduce a large chunk of the cannabis industry’s emissions.