Halogenated gases currently contribute 12% to overall radiative forcing. While actions under the Montreal Protocol on Substances that Deplete the Ozone Layer (Montreal Protocol) are already addressing CFCs and HCFCs, atmospheric concentrations of some HFCs (hydrofluorocarbons) are rising rapidly, by more than 23% each year. A global agreement to phase out HFCs under the Montreal Protocol is an immediately achievable, cost-effective rapid action with enormous and unrivalled near-term greenhouse gas mitigation potential. The Montreal Protocol is a proven
model working in the industrial sectors that produce HFCs, and has the necessary institutions in place to enable rapid and effective technology transfer in developing countries.