For several years, emissions of CFCs have been rising, in apparent defiance of a global ban in place since 2010. A new global detective effort has traced the source to two eastern Chinese provinces.
Almost 30 years ago the world responded to the realisation that our ozone layer was in trouble. The resulting Montreal Protocol was a rare example of global cooperation, but there’s no room for complacency.
Earth’s ozone layer shields us from harmful ultraviolet radiation. Nations have been working to reduce ozone-depleting chemicals since the 1980s, but recent studies show that there is still work to do.
Australia has ratified an agreement to phase out hydrofluorocarbons, a manmade compound once hailed as the saviour of the ozone layer. What went wrong?
The treaty to limit the destruction of the ozone layer is hailed as the most successful environmental agreement of all time. Three decades on, the ozone layer is slowly but surely returning to health.
While many people are willing to happily gamble with pharmaceuticals, which may offer the most trivial of benefits, they are not ready to believe the facts on climate change.
While the gases most responsible for global warming - carbon dioxide, methane and nitrous oxide - continue to climb, other industrial greenhouse gases are being brought gradually under control.
Much has been made of the domestic political roadblocks between US President Barack Obama and climate action. But by using existing treaties he can get around the hostile Congress and help cut global emissions.