Text of my ‘When Worlds Collide’ column published in Ceylon Today Sunday newspaper on 16 September 2012

Today, 16 September, is observed worldwide as the International Day for the Preservation of the Ozone Layer. The theme this year is “Protecting our atmosphere for generations to come”.

Exactly 25 years ago, governments of the world came together at a historic conference in Montreal, Canada, to adopt the Montreal Protocol on Substances that Deplete the Ozone Layer.

This legally binding international treaty has now been ratified by 196 states (including Sri Lanka) as well as the European Union. With such universal ratification, it is the world’s most widely subscribed international law.

It is an extraordinary success story of governments, experts and ordinary people coming together and acting resolutely to protect all life on Earth from the Sun’s harmful ultraviolet rays.

In a quarter century, it has rallied governments and industries in…