Column: Ozone success gives hope for climate

• 40 years ago, scientists discovered chemicals were destroying the fragile ozone layer.
• But the world came together and averted a catastrophe.
• If we can protect the ozone layer, we can find a way to protect the climate.

Climate change is not our first planetary pollution crisis. Almost 40 years ago, scientists discovered that chemicals called chlorofluorocarbons were destroying the fragile ozone layer that protects us from the sun's dangerous UVB radiation.

That would have condemned millions of people around the world to die from skin cancer, go blind with cataracts or suffer from immune diseases.

But the world came together and averted a catastrophe. The crowning moment came 25 years ago this month when the United States joined other nations to sign the world's most successful environmental treaty, called the Montreal Protocol. That's the treaty that put an end to the production of CFCs, rescued the ozone layer, saved millions of lives, and avoided a global catastrophe.

We too often take the rescue of the ozone layer for granted. A whole generation has grown up not hearing much about it, except maybe once each September when the recurring Antarctic ozone hole gets a brief mention in the news.

As we struggle for agreement on steps to curb the carbon pollution that's driving climate change, it's worth remembering, and learning from, our success in solving the ozone crisis.

The road to Montreal began in 1974 when two chemists, Sherwood Rowland and Mario Molina, discovered that CFCs released from aerosol sprays could rise miles into the stratosphere. There the sun's harsh rays split the CFCs apart, triggering chemical reactions that destroyed ozone molecules. As the ozone shield weakened, more of the sun's dangerous UV rays would reach the earth's surface.

The discovery made big news and galvanized Americans into action. Aerosol sales plummeted. Some companies redesigned their products. But others dug in. For more than a decade, the chemical companies that made CFCs reacted much like today's coal and oil companies: They denied the science, attacked the messengers, and predicted economic ruin.

But scientists and lawyers at the Natural Resources Defense Council (NRDC) fought back. In the next few years, Congress added ozone layer protections, federal agencies mopped up the last aerosols and the State Department began working on an international treaty.

But protecting the ozone layer was not a priority in Ronald Reagan's first years. EPA did nothing, treaty talks stalled and CFC use rebounded.

So NRDC sued EPA and to its credit, the Reagan administration followed the science and settled our lawsuit with a plan of action. The surprise discovery of a gaping hole in the ozone over Antarctica added new urgency. By 1986, even the chemical industry agreed CFC limits were needed.

In 1986, NRDC proposed the idea of a global phase-out. And to his credit once again, Reagan put a phase-out plan on the international negotiating table.

And 25 years ago this month, countries reached agreement on the Montreal Protocol. Every president since Reagan has supported the treaty. Every country on earth, from China to South Sudan, is now a full party.

It is not easy to convey the scale of the catastrophe that was avoided, the disaster that did not happen. Untold lives saved, cancers averted and agricultural disasters avoided. This is what NASA scientist Dr. Paul A. Newman calls "The World Avoided." You can read about it on NASA's website, and you can watch Dr. Newman explain it here.

So what are the lessons we've learned?

First, by acting together, nations have put the ozone layer on the road to recovery. The world has committed to eliminate the last ozone-depleting chemicals. And while national compliance with the ozone treaty commitments has been high, governments have to work harder to crack down on law-breakers.

Yet if we stick with it, scientists expect the Antarctic ozone hole to close for good around mid-century.

Second, we can do more under the Montreal treaty to fight climate change. There's already been a climate change bonus. CFCs are powerful heat-trapping pollutants and replacing them has slowed climate change by a decade. Had we not acted, the world would already be suffering even more severe droughts, floods and storms. This summer's extreme weather would have been even worse.

But one group of CFC replacements, called HFCs, poses a big problem. HFCs are also powerful greenhouse gases, and Dr. Newman's science panel has estimated that if we let them keep growing, by mid-century they'll trap as much heat as CFCs did at their peak.

Wisely, the Montreal treaty gives the parties the responsibility to ensure that replacement chemicals are safe — and that includes ensuring that they don't magnify climate change. So with other countries, the U.S. has proposed using this treaty to phase down HFCs. The vast majority of developed and developing countries want to move forward, but three countries — China, India, and Brazil — are blocking the start of negotiations. We'll be looking for a breakthrough at the next meeting, in Geneva this November.

Despite the stand-off on HFCs, the Montreal Protocol is proof positive that the Earth's nearly 200 countries can cooperate to save their citizens from a planetary pollution catastrophe.

If we can protect the ozone layer, we can find a way to protect the climate.

David Doniger is policy director of climate and clean air program at the Natural Resources Defense Council.

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