Today, we celebrate 35 years of the Montreal Protocol’s success in protecting the stratospheric ozone layer against synthetic chemicals that also cause climate heating. Thanks to a global agreement, humanity has averted a major health catastrophe due to ultraviolet radiation pouring through a massive hole in the ozone layer.

The Montreal Protocol is a success because, when science discovered the threat we all faced, governments and their partners acted. We adopted a global environmental agreement that has been universally ratified and decisively implemented.

The Montreal Protocol is a powerful example of multilateralism in action. With the many problems facing the world – from conflicts to growing poverty, deepening inequality and the climate emergency – it is a reminder that we can succeed in working together for the common good.

The Montreal Protocol has already contributed to tackling the climate crisis. By protecting plants from ultraviolet radiation, allowing them to live and store carbon, it has avoided up to an extra 1 degree Celsius of global warming. The Protocol’s work to phase out climate-heating gases and improve energy efficiency through its Kigali Amendment can further slow climate disruption.

But, only by mirroring the cooperation and speedy action of the Montreal Protocol elsewhere can we stop the carbon pollution that is dangerously heating our world. We have a choice: collective action or collective suicide.

On this International Day, let us pledge to emulate the cooperation shown by the Montreal Protocol to end the climate crisis and all our common challenges. And let us continue to back the Montreal Protocol’s essential work.