There are no simple solutions to complex problems like climate change. But there have been times in the past when the world came together to try to fix an environmental crisis.
How did we deal with acid rain, for example, or the hole in the ozone layer? And are there lessons for dealing with the larger issue of global warming?
1970s, ’80s and ’90s: Acid rain
It’s the 1980s and fish are disappearing in rivers across Scandinavia. The trees in parts of the forests are stripped of their leaves, and in North America some lakes are so devoid of life their waters turn an eerie translucent blue.
The cause: Sulfur dioxide clouds from coal-burning power plants travel long distances in the air and fall back to Earth in the form of acid rain.
“In the 1980s, basically the message was that this was the biggest environmental problem of all time,” says Peringe Grennfelt, a Swedish scientist who played a key role in highlighting the dangers of acid rain.
Headlines warning of the threats of acid rain were commonplace. For years there was confusion, denial and diplomatic wrangling, but once the science was settled beyond doubt, calls for action quickly grew louder. It has led to international agreements limiting pollutants from the burning of fossil fuels that acidify rain.
Amendments to the US Clean Air Act led to the development of a cap-and-trade system, incentivizing companies to reduce sulfur and nitrogen emissions and to trade any excess allowances. Each year, the cap was lowered until emissions fell dramatically.
So did it work? Acid rain is now largely a thing of the past in Europe and North America, although it remains a problem elsewhere, particularly in Asia.
But Canadian scientist John Smol, a young researcher in the 1980s, says that in many ways acid rain was a “success story”, showing that countries can come together and tackle an international problem. “If you don’t price pollution, people will pollute. We certainly learned that,” he says.
1980s: The ozone hole
In 1985, news of another looming environmental problem made headlines. Scientists from the British Antarctic Survey (BAS) have alerted the world to a large and expanding hole in the ozone layer over Antarctica. The damage was caused by chlorofluorocarbons – greenhouse gases better known as CFCs – which were then used in aerosols and refrigerants.
“All of a sudden it goes ‘boom’ and it goes down very quickly,” says BAS polar scientist Anna Jones, referring to the dramatic thinning of the gas belt that shields the planet from harmful UV rays.
Ozone over Antarctica had been declining since the 1970s, but the news that the hole now covered the entire Antarctic continent caused global alarm. In 1987, world leaders signed the landmark Montreal Protocol, which has been hailed as one of the most successful environmental treaties of all time.
Ozone-depleting chemicals were phased out, with the industry turning to “CFC-free” aerosol cans aimed at green consumers. “It was a global problem, but industry, scientists, policy makers came together,” says Dr Jones.
“They acted quickly, they acted with a mechanism that allowed for the continued tightening of this protocol. It’s a very important model for how you can make things work.”
Despite the success of the Montreal Protocol, there have been setbacks. Hydrofluorocarbons (HFCs), developed as alternatives to ozone-depleting chemicals, were discovered to be potent greenhouse gases.
And there has been a mysterious rise in CFCs detected in China. Both led to further action. And while the ozone hole is “on the road to recovery,” ozone-depleting chemicals remain in the atmosphere for decades, meaning repair is a long, slow process.
1920s to 2020s: Leaded gasoline
For decades we used leaded gasoline as a fuel – because companies added lead additives to help the gasoline burn more efficiently. Leaded gasoline releases lead particles into vehicle exhaust that can be inhaled, causing a variety of health problems, including heart attacks, strokes, and impaired mental development in children.
After a long battle between scientists, regulators and industry, a consensus emerged about the health risks, and wealthy nations banned leaded gasoline from the 1980s onward.
Use in developing countries persisted, however, because the fuel was cheaper to produce than unleaded gasoline. After a long campaign by NGOs, industry groups and governments, under the umbrella of the United Nations Environment Program (UNEP), the last drop of leaded petrol was pumped into a car’s tank in 2021.
And while the world has officially phased out leaded fuels, lead pollution remains in the environment in dust and soil.
Lessons on climate change?
With climate change dominating the news agenda, we hear very little about the ozone hole these days. However, there are parallels between these crises and the monumentality that is climate change.
For a long time, acid rain has been a source of international conflict, with some denying its very existence and the fossil fuel industry clashing with environmentalists. Sound familiar?
According to Professor Smol, the discussions and debates about acid rain were an education in the more complex issues of climate change. “The first lesson I learned was that we needed to effectively communicate the results of our studies, not just to other scientists, but to policy makers and the wider public,” he says.
“If there is an information gap, it will be filled immediately by interest groups.”
Professor Smol says the situation is even more complicated today, with the growth of social media and the spread of misinformation.
When it comes to the international push to phase out leaded fuels, Rob de Jong, head of UNEP’s sustainable mobility unit, says a key lesson has been the value of a harmonized approach. “The whole leaded oil campaign has been heavily invested in public awareness, heavily invested in social and community action, heavily focused on the impact this has on children.”
And the steps taken by the international community to reduce ozone-depleting chemicals show—on a smaller scale—the kind of cooperation that will be needed to tackle global warming.
“The climate change problem is much more complicated to solve than the ozone problem because we don’t have immediate alternatives to fossil fuels the way we had alternatives to CFCs,” says Dr Jones. “But that’s no reason not to do something – the problem is very important, it’s very big and they need to get on with it.
“When industry and governments came together in the past, they solved a world-threatening environmental problem – now they have to show they can do it again.”
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Top image credit: Getty Images. Climate band visualization courtesy of Professor Ed Hawkins and the University of Reading.