A crack in the natural-gas bridge

Abstract

Burning fossil fuels such as coal, gas and oil produces more than 80% of the world’s energy and more than 90% of global carbon dioxide emissions. Slowing and ultimately stopping climate change depends on decarbonization — the transformation of the global energy system into one that does not dump CO2 into the atmosphere. Because gas- fired power plants emit roughly half as much CO2 of gas for coal and oil can thus decarbonize the energy sector2 . In this issue, (page 482) uncover a serious . Progressive substitution and serve as a ‘bridge’ to a per unit of energy produced as coal-fired plants, the greatly expanded gas supplies promised by new hydraulic fracturing (fracking) methods have been celebrated as a means of cutting emissions1 more distant future when carbon-free, renew- able-energy technologies are more affordable and reliable than they are now3 McJeon et al.4 crack in the gas bridge: in the absence of new climate policies, increased supplies of natural gas may have little effect on CO2 emissions and could actually delay decarbonization of the global energy system.