Chilling Prospects 2022: Ozone Treaties – a global partnership for more sustainable cooling

Data analysis
Chilling Prospects 2022

Reflections on five years of the Kigali Amendment by the Ozone Secretariat

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Cooling covers a broad segment of the economy that uses refrigerants, many of which are controlled by the Montreal Protocol on Substances that Deplete the Ozone Layer. [1] It is part of more than 200 economic sectors that include comfort cooling, cold chain for agri-food systems and vaccines, and foam manufacturing. As such, the impact from the work undertaken by Parties under the Montreal Protocol is cross-cutting and contributes to almost all Sustainable Development Goals (SDGs) either directly or indirectly.

With the projected increase in global demand for cooling, [2] we need to move this sector onto a more sustainable path. Given its universal ratification and the concrete results it has achieved to date, the Montreal Protocol provides a well-established framework for transition to lower global-warming alternatives with tangible improvements in energy efficiency, safety and affordability of cooling equipment.  

The Ozone Secretariat and the UN Environment Programme (UNEP) have developed data hubs (i.e., the data centre of the Ozone Secretariat and the World Environment Situation Room of UNEP) with interactive features for the analysis of the data reported by the Parties to the Protocol. These data show that the global implementation of the Montreal Protocol has led to the phaseout of 99 percent of ozone-depleting substances (ODS), or 1.8 million ozone depletion potential (ODP) tonnes, globally. The remaining 1 percent (approximately 200,000–300,000 metric tonnes) is largely hydrochlorofluorocarbons (HCFCs). A global phaseout of ODS is expected by 2030.

Hydrochlorofluorocarbons (HCFCs) 1990 to 2020

Given the high global warming potential of many ODS, it is estimated that without the Montreal Protocol atmospheric carbon dioxide concentrations would have increased by an additional 115–235 parts per million by the end of the century. [3] This would have translated into a rise in global mean surface temperature of 0.5-1.0 °Celsius. In addition, the implementation of the 2016 Kigali Amendment to the Montreal Protocol, which added 18 hydrofluorocarbons (HFCs) to the list of controlled substances, is projected to prevent up to 0.4 °Celsius of global warming by the end of this century. While HFCs do not destroy the ozone, they warm the climate with a potential far greater than that of carbon dioxide.

In 2020, based on the annual statistical data reported by Parties on their consumption and production of controlled substances, developing countries phased out 35 percent of HCFCs from their baselines set at the levels of 2009–2010 while developed countries reached the full phaseout. According to the 2018 scientific assessment of ozone depletion, undertaken by the Montreal Protocol’s independent Scientific Assessment Panel, actions taken under the Montreal Protocol have led to long-term decreases in the atmospheric abundance of controlled ODS and the ongoing recovery of stratospheric ozone. Northern Hemisphere and mid-latitude ozone is expected to heal completely by the 2030s while Southern Hemisphere mid-latitude ozone is expected to do so in the 2050s. The Antarctic ozone hole is expected to close in the 2060s.

Antartic total ozone 1971 to 2019
Source: NASA Ozone Watch

Moving towards zero ozone-depleting cooling

The Kigali Amendment has been ratified by 131 Parties to date. Since its entry into force three years ago, Parties to the Montreal Protocol have been busy meeting the prerequisites for its implementation such as extending the existing licensing systems for export and import of controlled substances to cover HFCs, conducting situational analyses to estimate baselines for these substances (to be set at the level of 2020–2022 for developing countries) to measurably phase down their production and consumption, and implementing initial enabling activities and/or demonstration projects funded by grants from the Multilateral Fund for the Implementation of the Montreal Protocol. Parties to the Protocol are also encouraged to design and conduct their national phasedown programmes in coordination with other national priorities on climate change, energy efficiency and other relevant areas. The first milestone for most developing Parties under the Kigali Amendment is to freeze their production and consumption of controlled substances in the year 2024.

In its 2021 review of energy-efficient and low global-warming potential technologies, the Technology and Economic Assessment Panel of the Montreal Protocol indicated that the cooling sector consumed 20 percent of electricity produced globally in 2019, and the demand for refrigeration and air-conditioning units would increase significantly in the next few decades. If the rate of energy consumption by the cooling sector remains unabated and current refrigerants in the cooling system do not switch to lower global warming potential alternatives, the sector will contribute to global warming that surpasses the 1.5°C target of the Paris Agreement by 2030.

The review also identified a variety of existing best available technologies and policy solutions that need to be adopted and implemented urgently and at scale. Achieving the universal ratification of the Kigali Amendment will be an important opportunity for climate action. Full implementation of the commitments under the Amendment and the Montreal Protocol can help the world move towards zero ozone-depleting, low global- warming, safe and energy-efficient cooling. As the world slowly emerges from the pandemic, integration of considerations for more sustainable and affordable cooling into economic recovery packages will be essential for equitable, resilient and sustainable development. 


[1] The ozone layer filters out the sun’s harmful ultraviolet radiation that can otherwise cause a higher incidence of skin cancer and damage land and marine ecosystems including the capacity of some to store carbon.
[2] The Future of Cooling, International Energy Agency, 2018
[3] Summary Update 2021 for Policymakers, UNEP, Environmental Effects Assessment Panel, 2021

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