What is the Kigali Amendment?
Montreal is not Paris
The Paris Agreement on Climate Change has now entered into force. Its aim is to limit the “global” temperature rise to 2°C. Both agreements share the same goal but do not overlap.
IT’S ALL ABOUT THE FUTURE
Current consumption of HFCs has only a small future effect and so the answer depends on the volume of HFCs used in the future.
There have been a range of scenarios for projected future HFC emissions which determine the estimated effect of Kigali.
The most recent Scientific Assessment Report estimates that Kigali will reduce future global average warming in 2100 due to HFCs from a baseline of 0.3-0.5 °C to less than 0.1 °C.
THE IPCC SCENARIOS
The Kigali Amendment will significantly limit the future production and consumption of HFCs. Under the current control measures, emissions of HFCs are projected to peak around 2035. Without Kigali, surface temperature warming from HFCs might have been as high as 0.3°–0.5°C by 2100. With Kigali it is projected to be about 0.06°C by 2100.
THE VELDERS SCENARIOS
FOR HFC FUTURE EMISSIONS GROWTH
The projected 0.5°C contribution from HFCs comes from a 2009 paper by Velders et al.
Velders has published several scenarios for HFC emission growth and these have been used by some as a basis for the future climate impact of HFCs. The 2009 paper predicted a exponential growth in HFCs that, extrapolated, would result in an additional 1 W/m2 by 2100.
PROJECTIONS & EFFECTS
The Kigali Amendment will remove most of the Climate Impact of HFCs, the maximum benefit to global temperature is 0.4°C depending on future projections.
The 0.4°C reduction due to Kigali is not part of the 2°C envisaged by the Paris Agreement. Full implementation of the Paris Agreement is still required, including Energy Efficiency improvements facilitated by low GWP alternatives to HFCs
AN IMPORTANT STEP
The Kigali Amendment is an extremely important step in reducing future HFC emissions and should be fully supported and implemented.
Climate Change: ODSs, HFCs, Alternatives including HFOs
The top chart shows the projected emissions as actual tonnes for HFCs and low GWP alternatives, which includes HFOs and HCFOs.
The bottom chart shows their emissions as CO2– equivalents. Only marginal increases (small so hard to see on the chart) are projected for CO2-eq emissions of the low-GWP alternatives, despite substantial projected increases in their emission mass.
The atmospheric abundances of HFCs currently amount to about 1.5% of total emissions from all long-lived greenhouse gases as carbon dioxide-equivalent emissions. Radiative forcing from HFCs amounts to 1% (0.03 W m-2) of the 3 W m-2 supplied by all long-lived greenhouse gases (GHGs).
The Kigali Amendment to the Montreal Protocol is projected to reduce future global average warming in 2100 due to HFCs from a baseline of 0.3-0.5 °C to less than 0.1 °C. HFC emissions are projected to peak before 2040 and decline to less than 1 GtCO2-eq yr−1 by 2100, similar to the emissions in 2016 (0.88 GtCO2-eq yr−1).
Improvements in energy efficiency in refrigeration and air-conditioning equipment during the transition to low-GWP alternative refrigerants can potentially double the climate benefits of the HFC phasedown of the Kigali Amendment.
Explanatory Note: The Scientific Assessment of Ozone Depletion report states that HFC abundance in the atmosphere is 1.5% as a percentage of total emissions of all greenhouse gases. The Emissions Gap Report 2018 states that the annual emissions of F-Gases (HFCs, SF6 and PFCs) are 2.4%, as a percentage of the six GHGs (CO2, N2O, CH4, HFCs, SF6, and PFCs).
Source World Meteorological Organization Global Ozone Research and Monitoring Project – Report No. 58 Executive Summary Scientific Assessment of Ozone Depletion: 2018