Global carbon dioxide emissions from the energy sector stalled in 2014, the first time in 40 years during a period of economic growth, according to the International Energy Agency. By far the main culprit in global warming, carbon dioxide emissions stood at 32.3 billion tonnes in 2014, unchanged from the previous year. Carbon capture and storage is one way of reducing industrial greenhouse gas emissions. It involves recovering the carbon gas at its source and holding it in underground reserves.