Rethinking time-lagged emissions and abatement potential of fluorocarbons in the post-Kigali Amendment era
Heping Liu, Huabo Duan, Ning Zhang, Yin Ma, Gang Liu, T. Reed Miller et al. · 2024 · 15 citationsRead the paper
The Montreal Protocol has been successful in safeguarding the ozone layer and curbing climate change. However, accurately estimating and reducing the time-lagged emissions of ozone-depleting substances or their substitutes, such as produced but not-yet-emitted fluorocarbon banks, remains a significant challenge. Here, we use a dynamic material flow analysis model to characterize the global stocks and flows of two fluorocarbon categories, hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), from 1986 to 2060. We assess emission pathways, time-lagged emission sizes, and potential abatement measures throughout different life cycle stages while focusing on the role of banked fluorocarbons in global and regional decarbonization efforts in the post-Kigali Amendment era. Although fluorocarbon releases are expected to decline, the cumulative global warming potential (GWP)-weighted emissions of HCFCs and HFCs are significant; these will be 6.4 (±1.2) and 14.8 (±2.5) gigatons CO2-equivalent, respectively, in 2022–2060 in our business-as-usual (BAU) scenario. Scenario analysis demonstrates that implementing currently available best environmental practices in developed economies can reduce cumulative GWP-weighted emissions by up to 45% compared with the BAU scenario. The cumulative global warming potential-weighted emissions of hydrochlorofluorocarbons and hydrofluorocarbons are significant, which will be 21.2 (±3.7) gigatons CO2-equivalent in 2022–2060 under a business-as-usual scenario.
What the full text shows
Theory or simulation- Cumulative GWP-weighted emissions for HCFCs and HFCs from 2022–2060 under business-as-usual (BAU) scenario. — 6.4 (±1.2) and 14.8 (±2.5) Gt CO2-equivalent, respectively (BAU scenario, 2022–2060)
- Potential reduction in cumulative GWP-weighted emissions by implementing best environmental practices (BEPs) in developed economies. — up to 45% lower vs. BAU (Optimal scenario (S4), 2022–2060)
- Total global GWP of fluorocarbon banks in 2021. — 12.9 (±2.0) Gt CO2-equivalent (Global total, 2021)
- Contribution of the Industrial and Commercial Refrigeration (ICR) sector to GWP-weighted emissions (1986–2021). — 66% (Historical period 1986–2021)
- Projected contribution of the ICR sector to GWP-weighted emissions (2022–2060). — 57% (BAU scenario)
- Avoided emissions due to BEPs in non-A5 parties (1986–2021). — 3.8 (±0.5) Gt CO2-equivalent (Non-A5 parties, 1986–2021)
- Setup
- Global analysis of HCFCs and HFCs from 1986 to 2060 across five sectors (ICR, RAC, MAC, PUR/XPS foam, DRF) and regional groupings (A5 and non-A5 parties).
- How
- The study used a dynamic material flow analysis (MFA) model combining sales volume and Weibull-distributed lifespans to estimate stocks and flows. It applied the IPCC Tier 2a method to project historical and future emissions across manufacturing, use, and end-of-life (EoL) stages.
- Limitations
- Excludes HCFC-22 emissions from feedstock and aerosol applications. · Excludes certain HFC blends and non-refrigerant/blowing agent applications. · Uncertainties in consumption data and the randomness of natural/man-made hazards causing leaks. · Reliance on reported sales data which may differ from actual production.
Summarized by Gemma 4 from the open-access full text · 8 Oct 2026. Read it