 I'm Salvatur Babonis, and today's lecture is Lessons from the Ozone Hole. Before global warming became climate enemy number one, there was the Ozone Hole. The ozone layer high in the Earth's atmosphere prevents most of the Sun's damaging ultraviolet radiation from reaching the surface of the Earth. By the 1980s, the ozone layer was rapidly degrading due to the action of atmospheric pollutants with a large ozone hole in the atmosphere opening up every summer over Antarctica. Largely forgotten today, in the 1980s, the ozone hole was a widely discussed environmental catastrophe in the making. Ozone is a special form of the oxygen molecule composed of three instead of the usual two oxygen atoms. Ozone naturally forms and decays high in the stratosphere 20 to 40 kilometers above the surface of the Earth. In a natural cycle, the interaction of the Sun's ultraviolet radiation with oxygen in the atmosphere creates ozone, and then further interaction between ultraviolet radiation and ozone causes it to decay back into an oxygen molecule plus a loose oxygen atom. This process occurs over and over, absorbing ultraviolet radiation and preventing it from reaching the surface of the Earth. This stratospheric ozone is the same oxygen that you have heard about in ground level ozone. There's no chemical difference between the two, but there's no connection between the two ozone phenomena. Ozone forms at ground level through chemical reactions having to do with pollutants coming from car exhaust and forms part of the smog that you see over most large cities that clouds the air or makes it difficult to see long distances inside cities, especially on a hot summer day. That ozone forms close to the ground and stays close to the ground. It has nothing to do with the ozone that appears in the stratosphere. In the 1970s, American scientists began to warn that the Earth's ozone layer was vulnerable to erosion by human-made chemicals. The main culprits were chemicals called chlorofluorocarbons, or CFCs, which were used in refrigeration. Now, refrigeration is extraordinarily widespread. Of course, pretty much every house in the developed world, and in most developing countries as well, has a refrigerator. Many of them have air conditioners. Cars have air conditioners, which are very prone to leak coolant. Many of you have probably had to recharge the coolant in your car's air conditioner or have had coolant leaks in the car. Refrigerated trucks and storehouses maintain the world's food supply system. Refrigerated container ships supply the world's oceans. Refrigeration and cooling are everywhere in the modern world and use vast amounts of coolant, much of which ultimately leaks into the atmosphere in one way or another. The chlorofluorocarbons that used to be used as primary coolants in all of these systems were found to be depleting the Earth's atmospheric ozone. It's also possible that global warming is depleting the ozone layer. This is a little more speculative. Ironically, global warming is predicted to lead to cooler temperatures in the Earth's stratosphere, and those cooler temperatures are expected to be less conducive to the formation of ozone. This is less well established, but the connection between chlorofluorocarbons and the ozone hole very rapidly came to be accepted as established science between 1974 and 1985, despite the fact that the companies that manufacture chlorofluorocarbons aggressively argued that they were safe. Ozone depletion is very dangerous because ultraviolet radiation causes skin cancer, cataracts, and it even suppresses the immune system. Most of you have probably bought or own UV protection sunglasses, sunglasses that help protect your eyes from ultraviolet radiation. This is because ultraviolet radiation from the sun will contribute to the formation of cataracts, which most people develop in old age that ultimately cause blindness. Skin cancer is one of the most common forms of cancer, especially in high latitude countries like Australia, New Zealand, and also in Canada and the United States and Western Europe. These health impacts are most strongly felt in the high latitudes of the world because the Earth's ozone layer is thinnest in the high latitude areas, so over Antarctica and over the Arctic and Greenland. In fact, it was over Antarctica where the ozone hole was first directly observed. This graph shows the concentrations of stratospheric ozone in Antarctica from the beginning of measurements in 1979 through 2014. As you can see in the late 70s and early 1980s, levels of ozone over Antarctica were rapidly declining by 50%. Now, no one knows how much higher they may have been before the 1970s when there were no observations, but scientists observing the deterioration of the ozone layer over Antarctica became very alarmed. A similar deterioration also began over Northern Canada and Greenland, but had not progressed quite as far when chlorofluorocarbons were banned and the ozone layer began to recover. As you can see from this graph, though, the depletion of the ozone layer was stabilized by the mid-1990s, but the ozone layer still has not recovered. In 1987, the countries of the world agreed the Montreal Protocol on substances that deplete the ozone layer, a global treaty to take action to ban chlorofluorocarbons and help restore the ozone layer. The Montreal Protocol was actually an implementation treaty meant to implement the agreement reached two years earlier in the 1985 Vienna Agreement to take action against the formation of the ozone hole and against ozone depletion. In the 1987 Montreal Protocol, not only were chlorofluorocarbons banned, but a $3.5 billion fund was set up to help poorer countries pay for the transition from the use of CFCs to other more expensive refrigerants. The major donors to this fund were the rich, high-latitude countries. That is the countries that expected to be most impacted by the expanding ozone hole, by the depleting ozone layer. These were the U.S., Japan, and European countries in Canada who were major donors. In the case of the U.S., donating more than $700 million to the fund, Japan, more than $600 million to the fund, and these donations were put into a fund administered by the United Nations and mostly dispersed through United Nations and World Bank development programs to aid countries making the transition to other refrigerants besides CFCs. Ironically, some of the last CFC producing factories to close down were in Argentina. Factories that refused to close and ultimately had to be bought by the Argentine government using money from this fund. The factories were literally bought by the government and then closed down because the factories refused to stop producing chlorofluorocarbon-based refrigerants. Now, this is ironic because Argentina is one of the highest-latitude countries in the world. Argentina and Chile are the closest countries to Antarctica, and thus Argentina was likely to be one of the countries most affected by the expanding ozone hole, certainly one of the countries first affected by the expanding ozone hole, and yet even in Argentina the political will could not be summoned to give up the use of chlorofluorocarbons in refrigerants without compensation. Thirty years later, the Montreal Protocol is widely touted as a major success and example to be followed in our efforts to solve the problem of global warming yet the ozone hole over Antarctica has only been stabilized, not repaired. This is a graphic of the area covered by the ozone hole in 1986, which was actually tied for being the worst year for ozone depletion. I'm sorry, 2006, which was tied for being the worst year for ozone depletion. So even though the Montreal Protocol was signed in 1987 and began operation in 1989, even by the early 2000s the problem had not been solved, it had only been managed. I think that instead of being seen as a model for how the world can successfully address global warming, the Montreal Protocol might be read as something more like a cautionary tale. After all, rapid and comprehensive global action was only able to stabilize the atmosphere at a depleted level. It was not able to restore it. Now this is action that was taken very quickly. Eleven years after the first scientific papers suggesting the chlorofluorocarbons might damage the ozone hole, there was a global treaty to transition away from chlorofluorocarbons. We're now decades into our knowledge of the threat posed by global warming. There have been treaties, the Kyoto Protocol and now the Paris Treaty, but these treaties have no real enforcement mechanisms yet. We have the equivalent of the Vienna Treaty that is the world has agreed to do something, but we have no equivalent of the Montreal Protocol, an actual fund where countries have agreed to spend money to make a difference to end global warming. Second, political realities in the 1980s meant that companies enjoying local political patronage had to be paid off to stop producing CFCs. Countries, even countries threatened by the ozone hole were not able to take on small local constituents. A refrigerant factory defied governments attempting to address the ozone crisis. Well, that's not really a good sign. I mean, how many people would have to be paid off in order to stop global warming? Think of the amounts necessary to pay off large multinational oil firms or in some cases state-owned oil firms in order to address the threat of global warming. The amounts needed would dwarf the $3.5 billion Montreal Protocol fund. They would be almost incalculable. Third, chlorofluorocarbons are industrial products that can only be produced at point sources in factories. In fact, after the Montreal Protocol, a list of point sources of places that produced CFCs was identified. There were fewer than 200 in the world and each of those 200 factories was individually identified for closure and ways were sought to close each individual factory. Contrast to the situation with greenhouse gas emissions. They're produced everywhere. I mean, every single car in the world, every power plant, every cow produces greenhouse gas emissions. Methane farts from cows are one of the main sources of global warming. It's hard to imagine closing down those literally billions of point sources of carbon dioxide and methane emissions that contribute to global warming. Finally, ozone depletion was forecast to affect the mostly rich countries of the world first. The countries that were threatened by the ozone hole were countries like the United States, Japan, the United Kingdom, even the Soviet Union were threatened by the ozone hole. And those countries took action to stop poor countries from producing chlorofluorocarbons. With global warming, we have the exact opposite dynamic. We have most of the greenhouse gas pollutants being produced in rich countries. The rich countries of the world are the worst polluters of greenhouse gases and the greatest beneficiaries of greenhouse gas emissions. While it's the poor tropical countries that are those most likely to suffer the worst effects of global warming. Put that all together and I don't see much prospect for using the Montreal Protocol as a roadmap to solving the global warming crisis. Key takeaways. The ozone hole is a depletion of the Earth's ozone layer that protects the world from harmful ultraviolet radiation. That is, the layer protects the world, not the hole. Second, the 1987 Montreal Protocol banned the production and use of the chlorofluorocarbons that cause ozone depletion. And finally, the Montreal Protocol is usually held up as an example of how the world can succeed against global warming. But I think it is a highly questionable, highly problematic example. Thank you for listening. I'm Salvaturba Bonus. You can find out more about me at SalvaturbaBonus.com where you can also sign up for my monthly newsletter.