A model for estimating future emissions of sulfur hexafluoride and perfluorocarbons

Sulfur hexafluoride (SF6), perfluoromethane (CF4) and perfluoroethane (C2F6) are strong greenhouse gases with long (>1000 year) atmospheric residence times. We derive emission factors for the major anthropogenic sources and project future emissions for 5 regions and the world. Although firms in many industrialized countries are already limiting emissions, without further policy intervention global emissions will rise 150% (CF4 and C2F6) and 210% (SF6) between 1990 and 2050; radiative forcing will increase 0.026 W m-2. Full application of available low-cost and costless policies in industrialized nations would cut that radiative forcing by one-quarter. Increased forcing due to these gases is small (