Following is UN Secretary-General António Guterres’s message on the International Day for the Preservation of the Ozone Layer, observed 16 September:

The international treaties to protect the ozone layer have made a dramatic and measurable difference to protecting people and planet. They show the power of multilateralism. And they should inspire hope that, together, we can avert the worst of climate change and build a sustainable and resilient world.

Limiting the rise in global temperature to 1.5°Celsius is still possible if we immediately and drastically accelerate climate action. I have proposed a Climate Solidarity Pact and an Acceleration Agenda to help achieve this. I urge all leaders to work together to put them into effect, and to support these efforts by getting behind the Kigali Amendment to the Montreal Protocol and limiting planet-heating hydrofluorocarbons.

Fully ratifying and implementing the Kigali Amendment could avoid up to 0.5°C of warming by 2100. Combining the transition away from planet-heating gases with energy efficiency measures in cooling equipment could double this figure.

I call on all countries to ratify the Amendment. And I urge Governments, along with business leaders, civil society, academia, youth groups, local communities and others to intensify efforts to bring about real change and to ensure developing countries have the support they need to do so.

Let’s harness the spirit of the Vienna Convention and the Montreal Protocol to build a world where humans, nature and the planet thrive together.