The Montreal Protocol has not only preserved the ozone layer, it has helped save the Earth from a time bomb of climate change.
The historic ozone treaty was concluded 35 years ago this month, at a time when climate and ozone science was much less developed than it is today. Yet every nation has signed on, agreeing to binding commitments to reduce the production, consumption and emissions of chemicals responsible for thinning the ozone layer that shields the planet from the sun’s most harmful radiation. The same set of chemicals turned out to be extremely potent greenhouse gases as well, and reducing them has bought the world valuable time to deal with the climate crisis.
“If we let the [chlorofluorocarbons (CFCs)] continue to grow, we would have had the effects of climate change that we are feeling now…a decade ago,” said David Doniger, a lawyer with the Natural Resources Defense Council who has worked on the issue since the 1980s. would be much worse now.”
The protocol’s status as a climate treaty was bolstered by the 2016 Kigali Amendment – named after the Rwandan capital where the agreement was drafted – which targeted a class of refrigerants that were non-depleting. of ozone but forced the climate. Scientists say the global phase-down of hydrofluorocarbons (HFCs), which the United States is now poised to join after a key Senate vote on Wednesday, has the potential to stave off half a degree of warming Celsius by 2100.
Scientists, lawyers and others who have worked on the issue for decades say that long before international negotiators struck the HFC deal, the ozone treaty had prevented a particularly harmful set of climate super-pollutants were incorporated into the air conditioning and refrigerators that developing countries used. finally acquire.
David Fahey, director of NOAA’s Chemical Sciences Laboratory and co-chair of the Montreal Protocol’s Scientific Evaluation Committee, was among the scientists who, in 1987, flew a NASA research aircraft into the ozone hole that appeared over Antarctica. There were several competing theories at the time as to why the hole was appearing, he said.
But the NASA trip, he said, “created a smoldering plot, as we call it, that was really essential evidence that chlorine was destroying ozone on the scale of what would cause the hole. Antarctic Ozone”.
The world reacted quickly.
“The same month we were in southern Chile flying to Antarctica, in Montreal, the Montreal Protocol was being signed,” he said. “And it was basically signed without knowing for sure what was causing the Antarctic ozone hole.”
The new agreement was not only a leap of faith when it came to science, but it had attributes that have never been replicated in any subsequent climate treaty despite much higher levels of scientific certainty.
The treaty is universal with 197 member countries. It is legally binding with penalties for countries that flout its provisions. And it’s fully funded, meaning poorer countries that might not have been able to meet its chemicals phase-out targets got help from wealthier ones.
“There is no other forum that has these three dimensions,” Fahey said, noting that the 2015 Paris Agreement on climate change is based on voluntary commitments with no penalties for breaches.
“Probably the underlying problem with the climate change situation is that we don’t have such a forum,” he said.
Key role of DuPont scientist
Fahey said there was some understanding among scientists early on that CFCs played a role in climate change as well as ozone depletion. But that role was clarified by a scientific study he and four other scientists published in 2007, which looked at the “worlds averted” by stemming the growth of chemicals.
The report showed that without the Montreal Protocol, the use of CFCs would have exploded. Under a conservative scenario by 2010, chemicals would have had a greenhouse gas content almost equal to half the carbon dioxide emissions from all other sources. The effect on the climate would have been catastrophic.
“I think the estimates are in the range of 2 more degrees by mid-century,” said Susan Solomon, a professor of environmental studies at the Massachusetts Institute of Technology.
She noted that if the world had continued on its trajectory of increasing CFC use until 2050, the consequences for the ozone layer would have threatened the health and survival of all living things on the planet, including humans. It could have forced action, she said.
“The good news is that we avoided all of that, and not only did we save the ozone layer, but we also got a huge win for the climate,” she said.
While CFCs had the greatest impact on climate change, the hydrochlorofluorocarbons (HCFCs) that temporarily replaced them still had significant climate consequences. After the publication of the 2007 document, parties to the Montreal Protocol quickly decided to shorten the treaty schedule for HCFC phase-out, an adjustment which Fahey said was the first decision made under the Montreal Protocol. to reduce global warming.
HCFCs have been replaced by HFCs. And HFCs, which have no effect on ozone, were to be the final destination of the Montreal Protocol. But they are climate superpollutants that can be thousands of times more potent than carbon dioxide.
Industry was initially reluctant that the use of HFCs would have a significant impact on climate change. But Fahey credits an industry scientist, DuPont’s Mack McFarland, with changing the discussion.
“What Mack understood was growth in the developing world,” he said. “That the developing world was catching up with the developed world.”
McFarland began speaking to delegates at annual Montreal Protocol meetings about the role HFCs could potentially play in driving climate change, Fahey said.
“It became one of his main messages not only to delegates, but also to scientists and technologists,” he said. “And it wasn’t extremely well received or immediately received. And even the scientists – I’m one of them – didn’t really get it, so to speak.
But in 2009, McFarland, Fahey and the other scientists who had collaborated on the 2007 paper on the climate implications of the protocol published a paper on the effects of running global air conditioning and refrigeration units on HFCs. And its findings sparked the negotiations that ultimately led to the creation of the Kigali Amendment eight years later.
Solomon said she was shocked when the Senate voted this week by a 69-27 margin to join the Kigali Treaty. The agreement entered into force on January 1, 2019, after reaching a ratification threshold. The United States is the 138th country to sign.
But Solomon said that in the 1970s and 1980s, the United States led the charge in global protection of the ozone layer.
“I think the main credit should go to the American people,” she said.
Aid to poor countries
When ozone science was in its infancy, shortly after scientists Sherwood Rowland and Mario Molina demonstrated in 1974 that CFCs damaged ozone, but before the extent of the damage was known, American consumers have stopped buying aerosol deodorants and hair sprays.
The consequences have been transformational. US personal care products accounted for 75% of global CFC use in 1974. Falling demand forced industry to seek alternatives and made the Montreal Protocol possible.
And countries that are now showing leadership on climate change and other issues have clung to their aerosol products.
“The Europeans were actually on the other side of the negotiating table,” Solomon said. “It was us saying, ‘We should get rid of these compounds, we have substitutes, let’s move on. Let’s save the planet.’ And that was Europe saying, “Well, you know, we don’t really see that need the way you do.”
Solomon also credited former President Barack Obama and former Secretary of State John Kerry with creating the geopolitical momentum that carried Kigali across the finish line.
The direct climate benefits of the protocol reductions in CFCs, HCFCs and now HFCs are also not complete.
Solomon pointed out that the protocol’s multilateral fund has helped poor countries gain access to refrigeration, reducing emissions from food waste and spoilage.
NRDC’s Doniger referred to a published study in Nature last year which found that without the ozone-preserving benefits of the Montreal Protocol, much less CO2 would have been absorbed over the past 35 years as the global biosphere disintegrated.
“Damage to trees and other vegetation would have meant that they would have absorbed much less CO2 of the atmosphere,” he said.
The Nature The study argues that the protocol prevented a warming of 2.5 degrees Celsius. For context, scientists have warned that the world – and especially vulnerable countries – will suffer catastrophic damage if warming exceeds 1.5°C.
Reprinted from E&E News courtesy of POLITICO, LLC. Copyright 2022. E&E News provides essential information for energy and environmental professionals.