Protocol shows way on climate

World Ozone Day yesterday marked 33 years since the signing of the most successful international environmental agreement ever: the Montreal Protocol on Protection of the Ozone Layer.

Kiwi scientists played a big part in contributing to the global scientific community’s understanding of ozone depletion and in coming up with solutions. I know, because Iwas one of them. Now, I think it’s time to expand it so that it can help address climate change.

The Montreal Protocol is an achievement that the world can be proud of: in the space of three decades, we essentially solved a problem that once looked like it would be a dire threat to humanity.

If ozone depletion had continued unabated, our already-high rates of skin cancerwould have skyrocketed. By the second half of the century, the time for skin damage from exposure to sunlight would have decreased by more than a factor of three, down to less than five minutes for some. It wouldn’t have been safe to cross the road without sun protection.

By contrast, in the last three decades we have failed painfully to take the steps necessary to prevent catastrophe in the face of climate change, and now we’re starting to see the effects. This winter was the warmest in New Zealand history. Around the world, we’re seeing increased incidences and intensities of wildfires, floods, droughts, and hurricanes, with devastating effects – and all too little action.

So why haven’t we been able to replicate the success of the Montreal Protocol for climate change?

And, 33 years since its signing, what lessons might we take from that historic agreement?

As a principal research scientist at Niwa Lauder in Central Otago, I spent decades studying the causes and effects of ozone depletion alongside other scientists whose names you likely have never heard of but who nevertheless were held in the highest regard by their peers internationally: Greg Bodeker, Paul Johnston, Gordon Keys, Ben Liley and Andrew Matthews, to name a few. I’ve written about these people and their efforts in my book, Saving Our Skins, published in July.

My colleagues and Iwere part of a global effort that curbed further decreases in ozone. At Lauder, we did that by monitoring the amount of ozone in the atmosphere, along with all the gases involved in its depletion, and contributed to a global understanding of how they are linked. We showed, unequivocally, that the UV increases stemmed from ozone depletion, informing the understanding that underpinned the Montreal Protocol.

The world was able to take effective action because everyone who understood the issues agreed it was necessary, few people challenged the science, and governments supported it.

This was a huge international effort involving politicians, diplomats, industry leaders, lawyers, scientists, and environmentalists. Atmospheric researchers like us were a small but important part of the effort. The change wasn’t immediate because the chemicals harmful to ozone are long lived, but it has still been impressively fast. Although it cost a lot of money, the benefits are huge. New understanding brought new technologies and the problem was solved.

Climate change presents an even bigger challenge. In the three decades since the signing of the protocol, the concentration of carbon dioxide in the atmosphere has risen from 335 parts per million to 415 ppm this year – nearly 25 per cent.

Ifwe continue on this path, global temperatures are set to increase above pre-industrial levels by more than 2 degrees this century, leading to sea level rises and climate effects that will render large swaths of Earth uninhabitable.

Hundreds of millions of people may die or be displaced. New Zealand, with its coastal settlements, is as vulnerable as any country. And with less reliable water and food supplies in an increasingly overpopulated planet, New Zealand will also be a target for climate refugees.

Why, if the Montreal Protocol has shown that strong collective action is possible, is it still going wrong with climate change? Two reasons:

First, the gases responsible aren’t all man-made. They occur naturally as well. It’s the increasingly large man-made fraction of them that’s causing the problem. Second, the people who profit by fixing the problem are a different group from the people who caused it.

The chemicals needed to replace ozone-depleting chlorofluorocarbons (CFCs) and solve the ozone problem were made by the same companies that manufactured the problematic chemicals. They profited in the changeover.

But in curbing climate change, the profiteerswill be the renewable energy and electric transport sectors, not the fossil fuel industries that perpetuated the problem.

And so we need amassive global effort from governments, industry, and ordinary people to fully end our dependence on fossil fuels as soon as possible. We were able to live without CFCs and in fact produce even better technologies that created more wealth. The same will be true of oil and coal, which can be supplanted by superior technologies, such as electric transport and solar energy.

And again, New Zealand can play its part. We should enthusiastically embrace electrification of our transport sector, continue to hold the line against new drilling projects, invest heavily in making our electricity supply 100 per cent renewable, and disinvest in fossil fuels to once again lead the way for massive positive environmental change.

We should also extend the development of a relatively new initiative, the Kigali Amendment, which expanded the Montreal Protocol so that it covers a new group of chemicals: hydrofluorocarbons (HFCs). HFCs replaced CFCs because they had no effect on ozone; but they are potent greenhouse gases, contributing to climate change.

If the Kigali Amendment is broadened, it may open the door to bringing the man-made component of other warming substances, such as carbon dioxide, methane, and nitrous oxide, under the Montreal Protocol’s control.

As it enters middle age, the Montreal Protocol might find a second life that is even more important than its first.

In the space of three decades, we essentially solved a problem that once looked like it would be a dire threat to humanity.’’ Richard McKenzie