
Kigali Amendment

The Kigali Amendment to the Montreal Protocol is an international agreement to gradually reduce the consumption and production of hydrofluorocarbons (HFCs). It is a legally binding agreement designed to create rights and obligations in international law.
The Montreal Protocol was originally created to preserve and restore the ozone layer, and it worked. The Protocol was an agreement between participating countries to phase out certain ozone depleting gases. HFCs were used to replace the substances banned in that agreement because they have zero impact on the ozone. However, HFCs are powerful greenhouse gases that contribute to climate change, so this amendment adds HFCs to the list of chemicals that countries promise to phase out.
As of April 16, 2021, 119 states and the European Union have ratified the Kigali Amendment. The US and China have not ratified the amendment yet, but in April 2021 both countries pledged to do so.
Context.
Many industrial products, including heat pumps that operate on a refrigerant and propellant aerosols, require non-flammable fluids capable of passing easily from gaseous state to liquid state and having significant latent heat.
Historically, chlorofluorocarbons (CFCs) were used in these applications, but we discovered in the 1970s the deleterious effect of these gases on the ozone layer, which was rewarded by a Nobel Prize in Chemistry in 1995. The Montreal Protocol, signed in 1987 by many states and entered into force in 1989, decided to phase out CFCs. The use of HFCs then developed as a replacement.
These gases save the ozone layer, but they are powerful greenhouse gases. While their lifespan in the atmosphere is quite short, they filter infrared waves very strongly. For example, HFC-23 has a global warming potential (GWP) at 100 years of 12,400, compared to just 1 for . Basically, each molecule of HFC-23 is 12,400 times more powerful as a greenhouse gas than . Eliminating emissions of these gases could significantly lower the effects of global warming and may avoid a full half a degree Celsius of warming by the end of the century.
Details of the agreement.
Article 5 of the Montreal Protocol created separate standards for developing countries and non-developing. Whether a country was categorized as developing or non-developing depended on individual economic conditions at the time of the agreement or pending special request. Because the Protocol was created in the 1980s and countries economic situations have changed, the Kigali Amendment created three updated groups for compliance with the additional terms.
The first group, which includes the “old” industrialized countries, is committed to reducing the use of HFCs by 45% by 2024 and by 85% by 2036, compared to their use between 2011 and 2013. A second group, which includes China and Brazil, is committed to reducing its consumption by 80% by 2045. Finally, this deadline is extended to 2047 for the rest of the countries, including India and a number of countries in the Middle East, which are large consumers of air conditioning.
In addition, Parties that experience monthly average temperatures over 35 degrees Celsius for at least two months per year, over a period of 10 consecutive years, may request a waiver.