Global Warming Potentials for the C₁-C₃ Hydrochlorofluorocarbons (HCFCs) Included in the Kigali Amendment to the Montreal Protocol

Abstract

Abstract. Hydrochlorofluorocarbons (HCFCs) are ozone depleting substances and potent greenhouse gases that are controlled under the Montreal Protocol. However, the majority of the 274 HCFCs included in Annex C of the protocol do not have reported global warming potentials (GWPs) that are used to guide the phase-out of HCFCs and the future phase-down of hydrofluorocarbons (HFCs). In this study, GWPs for all C1-C3 HCFCs included in Annex C are reported based on estimated atmospheric lifetimes and theoretical methods used to calculate infrared absorption spectra. Atmospheric lifetimes were estimated from a structure activity relationship (SAR) for OH radical reactivity and estimated O(1D) reactivity and UV photolysis loss processes. The HCFCs display a wide range of lifetimes and GWPs dependent on their molecular structure and H-atom content of the individual HCFC. The results from this study provide reliable policy relevant GWP metrics for the HCFCs included in the Montreal Protocol in the absence of experimentally derived metrics.