In the 1970s, atmospheric scientists noticed the thickness of the ozone layer in the upper atmosphere, the layer of gas that deflects much of the sun?s radiation, had started thinning. The primary culprit was chlorofluorocarbons (CFCs), a chemical compound present in everything from aerosol cans to refrigerators to solvents. By the mid-1980s, it was on track to be wiped out in the next few decades. Fast-forward to today: The ozone is on the path to recovery. Experts estimate that by 2050, it will be back to the state it was in the 1980s.
When the ozone layer suddenly started to hurtle toward disaster, the world responded ? with consumer boycotts, political action, a major international treaty called the Montreal Protocol, and a huge investment in new technologies that allowed for a rapid phaseout of CFCs. The efforts effectively halted new CFC production by the 1990s and early 2000s, and CFC emissions have been steadily falling since the treaty went into effect in 1989.
The chemicals that replaced CFCs are called hydrofluorocarbons (HFCs), which are less dangerous to the ozone layer. But they?re still potent greenhouse gases ? thousands of times more powerful than carbon dioxide at trapping heat in our atmosphere. Twenty years ago, they were seen as an environmental step forward. Today, phasing them out is seen as a critical step to head off the worst of climate change. Earlier this year, the United States belatedly signed the 2016 Kigali Amendment, which extends the Montreal Protocol to almost entirely phase out HFCs over the next 30 years ? 197 countries have adopted the agreement.
The worldwide effort to heal the ozone layer reveals that while human ingenuity can solve our problems, it can also create new ones as it does. The campaign to phase out CFCs was a huge success. Even with the complications and caveats, it should be seen as an instructive success story ? one that can perhaps inform our response to the climate crisis.
?
https://www.vox.com/future-perfect/22686105/future-of-life-ozone-hole-environmental-crisis
