The Kigali Amendment, Hydrofluorocarbons and how they may impact our climate

The Kigali Amendment, Hydrofluorocarbons and how they may impact our climate

By: Dylan Gordon


The discovery and subsequent introduction of high potency greenhouse gases has caused global concern with the threat of ozone depletion and climate instability leading to the enactment of international agreements to combat some of these challenges to our world. The Kigali Amendment, a provision of the Montreal Protocol, was created with a specific super pollutant in mind, Hydrofluorocarbon-23, better known as HFC-23. HFC-23 is a man-made organic compound that is commonly used as a refrigerant or for air conditioning.1 HFC-23 has a high global warming potential, meaning it possesses a great likelihood to contribute to global warming because the compound is more potent than other commonly found greenhouse gases, such as carbon dioxide. The potency of these gases is determined by the amount of energy it absorbs, its atmospheric lifetime, and the specific type of radiation it absorbs and displaces, all of which contribute to its climate impact. In fact, scientists Piers Forster and Venkatachalam Ramaswamy report that HFC-23 has a climate impact nearly 12,000 times that of carbon dioxide.2 As our climate gradually changes, powerful greenhouse gases such as HFC-23 are becoming recognized as a threat to climate stability. 

Surprisingly, hydrofluorocarbons were developed in order to replace substances that were starting to deplete our ozone layer under the Montreal Protocol, an international treaty designed to limit the production of substances that threaten our atmosphere.  Hydrofluorocarbons began to be manufactured and consumed for air conditioning, refrigeration, aerosols, solvents, and even fire protection. Despite hydrofluorocarbons starting out as an alternative to gases that were threatening the ozone layer, their high potency made it difficult to rely on because they contributed to a buildup of heat in our atmosphere. But luckily, hydrofluorocarbons are not the only alternative. In fact, the Energy Information Administration declared that technologies that are HFC-free have already been developed and chemical alternatives such as water, hydrocarbons, carbon dioxide (CO2 or R-744) or ammonia (R- 717) exist with a significantly lower potency and less of a climate impact.3

Figure 1: Global hydrofluorocarbon consumption by year

In the age of climate change, the use of hydrofluorocarbon poses a significant threat, yet they are still being used and produced en masse. Despite expectations of an 87% drop in the number of hydrofluorocarbons being produced, K. M. Stanley of the University of Bristol reports that the number of hydrofluorocarbons has not only increased but is higher than at any point in history.4 The world is becoming more reliant upon HFC-23 despite international agreements opposing its use. 

According to the Energy Information Administration, one of the largest producers of the gas, the Chemours Company, had broken a commitment it made to the Obama Administration to eliminate its by-product emissions of HFC-23. Despite this commitment, a single facility of Chemours Company accounted for 64% of all HFC emissions reported to the Environmental Protection Agency.5 As a result of this broken commitment, the Energy Information Administration has called on the company to cease activities that lead to the release of HFC-23 and to work on restoration projects. The lack of enforceable policy and neglect by the largest producers of HFC-23 has been cited as a reason for countries where the majority of these gases are being produced like the United States, China, India, and Russia to ratify the Kigali Amendment.   

The Kigali Amendment is a new provision of the Montreal Protocol, and was created to “phase down” the use and emissions of HFC-23 with a goal to achieve an 80% reduction of their use by 2047 according to UNIDO, or the United Nations Industrial Development Organization.6 The amendment is believed to have a substantial impact on global climate by decreasing the amount of greenhouse gases with a high global warming potential in our atmosphere. UNIDO estimates that the amendment will be responsible for avoiding a 0.5 °C increase in the global temperature when ratified. If the reduction was to proceed as planned, it would have a substantial impact in the fight against climate change.

The continued use and reliance on hydrofluorocarbons pose a great threat to climate stability and despite the existence of alternatives, hydrofluorocarbons are still being used by some of the world’s major economies. This issue is primarily due to a lack of policy and initiative by nations who contribute the most to HFC emissions. But this may soon change; according to the White House, the Biden Administration has signed an executive order on tackling the climate crisis. This order includes having the secretary of state send a package to the senate to advise and consent to the U.S. ratification of the Kigali Amendment.7 This action is said to signal a change as the NRDC, an environmental advocacy group, openly declares that the U.S. ratification of the Kigali Amendment will gesture to other major economies to follow suit.8 With climate friendly compounds such as H20, CO2, and other hydrocarbons existing in abundance and alternative refrigerants or technologies on the rise, hopefully with U.S. ratification, the Kigali amendment will be able to incite real change in the global reliance on hydrofluorocarbons.


Figure 2: Map of countries who ratified the Kigali Amendment as of July 2020.9 

Posted: April 9, 2021


Works Cited
1 National Research Council (US) Subcommittee on Exposure Guidance Levels for Selected Hydrofluorocarbons. Submarine Exposure Guidance Levels for Selected Hydrofluorocarbons: HFC-236fa, HFC-23, and HFC-404a. Washington (DC): National Academies Press (US); 2000. 3, Hydrofluorocarbon-23. Available from: 
2 Forster, P., Ramaswamy, V., Artaxo, P., Berntsen, T., Betts, R., Fahey, D.W., Haywood, J., Lean, J., Lowe, D.C., Myhre, G., Nganga, J., Prinn, R., Raga, G., Schulz, M., & Van Dorland, R. Miller, H.L. (Ed.). (2007). Changes in Atmospheric Constituents and in Radiative Forcing Chapter 2. United Kingdom: Cambridge University Press.
3What are hydrofluorocarbons? (n.d.). Retrieved March 24, 2021, from
4 Stanley, K.M., Say, D., Mühle, J. et al. Increase in global emissions of HFC-23 despite near-total expected reductions. Nat Commun 11, 397 (2020).
5 EIA calls on CHEMOURS to immediately End Activities Causing HFC-23 EMISSIONS. (n.d.). Retrieved March 24, 2021, from
6The Montreal protocol evolves to fight climate change. (n.d.). Retrieved March 24, 2021, from
7-Executive order on tackling the climate crisis at home and abroad. (2021, January 27). Retrieved March 24, 2021, from
8  January 27, 2. (2021, January 28). Biden announces move to RATIFY KIGALI amendment ON HFCS. Retrieved March 24, 2021, from
9 Global ratification status of kigali amendment to montreal protocol phasing down hfcs. (n.d.). Retrieved March 24, 2021, from