Saving our Skins: Chapter 10. Finding the Culprit
Saving our Skins: Chapter 10. Finding the Culprit
The continuing story of “Saving our Skins”. Conspiracy theories and the “Merchants of Doubt”.
Updated September 5, 2021.
The discovery of the ozone hole galvanised the atmospheric science community. And our group at Lauder would be right at the centre of the action. More money materialised and our research blossomed. They were exciting times and I was glad we had turned down the offer to move to Wellington.
But not everybody agreed that there was a problem with ozone. And even if there was, why should we blame ourselves? How could a few man-made chemicals have such a big effect? Why was it so much worse in Antarctica? Why not the Arctic as well? It wasn’t fair. Only 10 percent of the world’s population lived in the southern hemisphere. Why should we have to bear the brunt of a problem caused half a world away?
These doubters didn’t understand the physics and chemistry, and especially the significance of the catalytic cycles involved, where a single chlorine atom could be responsible for the destruction of 100,000 ozone molecules. In 2010, the naysayers would be labelled the “Merchants of Doubt” in a whistle-blowing book with that title authored by Naomi Ereskes and Erik M. Conway. The Merchants of Doubt are a small group of scientists bankrolled by established industries to sow the seeds of doubt on issues where mandated solutions would affect profitability. Decades earlier they had worked for cigarette companies sowing the seeds of doubt on whether tobacco is harmful to health. Their success caused the unnecessary deaths of millions of smokers for every year of delay. They were also extremely successful in delaying action on ozone depletion. They even denied the existence of the Antarctic ozone hole. Their tactics delayed action on ozone depletion, but fortunately their actions would not be terminal.
They were still rabbiting on much later when we showed the world that the consequences of ozone depletion weren’t confined to Antarctica. That was in 1999, when we published an article in the American journal Science showing that peak summertime UV levels in New Zealand had increased by about 10 percent during the 1990s due to ozone depletion. One of those merchants of doubt, Fred Singer, questioned the validity of our result. In a letter to the editors of the journal he accused us of “cherry picking” the data to support our conclusion. But after the publishers received our response to the criticisms, Singer’s concerns were not published. As it turned out, while the conclusions of our paper were fine, the timing was rather fortuitous. If we had left it any longer, the paper probably would not have been accepted for publication in Science, because the pattern of increases in UV that was so clear through the 1990s was much less obvious after the turn of the century, as ozone levels began to stabilise.
This hiatus in the increase of UV after 1999 was no doubt a consequence of international controls on ozone-depleting substances, which were by then kicking in. The manufacturers of CFCs had eventually come on board and supported their regulation, but only after they had developed suitable replacement chemicals for the old CFCs. Because only a small number of companies had the know-how, they could now make more money by supporting the regulations than by delaying them. This is a key point of difference between solving ozone depletion and solving climate change.
The merchants of doubt are still active and still successful. Nowadays their focus is climate change. While professional scientists who understand the issues are almost universally convinced of the importance of human-induced climate change, others are determined to tell everybody that climate change is a hoax.
Some of these climate-change deniers are unwitting pawns in a bigger game being orchestrated by the Merchants of Doubt and their disciples. I find it particularly galling when scientists who are justifiably respected in their own fields elect themselves as spokesmen for climate denial, even when atmospheric science is far outside their area of competence. Perhaps I’m a bit sexist by using the word “spokesman”. Would “spokesperson” be more appropriate? I think not. For some reason, just about all climate deniers are grumpy old white men. Fortunately, they are gradually fading away. But will the damage they have done be retrievable?
A typical example of one of these deniers lives not far from me. His name is Jock Ellison and he was based at the Invermay Agricultural Research Station near Dunedin before his retirement. We cross e-mailed (increasingly crossly) a few times after I heard him deliver a climate-denial talk at our local rotary club. I tried to explain the true picture and where he had gone wrong, but his position was totally intractable. He was quite determinedly dismissive, possibly because he felt he had to be as a (self-elected) representative of the agricultural community. If any government actions on climate change were required, they would probably suffer. With our economy dominated by agriculture, New Zealand is the only OECD country for which CO2 is not the dominant greenhouse gas. Together, the effect of emissions of methane from livestock and emissions of nitrous oxide from livestock excrement and fertilisers, contribute more than 50 percent of our warming.
To laymen Jock’s voice may still carry weight, but more informed opinion on the subject should trump his. To atmospheric scientists like me, the position he takes merely shows his ignorance of a subject outside his area of expertise. It’s obvious that if you have toothache you should listen to your dentist, not your motor mechanic. But if your car breaks down, a motor mechanic will have better advice than your dentist. The same principle applies here.
But for other deniers, much more reprehensibly, their climate scepticism is really an act of “wilful ignorance” because the solutions aren’t palatable or may reduce profits. The truth, as Al Gore put it, is “inconvenient”. For ozone depletion, the same companies that caused the problem could profit from solving it. But the parties responsible for increasing greenhouse gases (GHGs), the oil and mining industries, stand to lose if those activities are regulated. Unless they reposition themselves successfully, the big profit takers of the 20th century will be superseded by a new breed of profit takers in the 21st century: those running with greener technologies that harness and make use of renewable energy.
I’ll give old Jock the benefit of the doubt, but the current (2016 to 2020) president of the USA clearly represents both denier categories. Trump’s very first action as president in 2016 (after lying about crowd size at his inauguration) was to renege on US support for the recently agreed Paris Climate accord. His action was sheer bloody mindedness, as there was no financial cost to their participation. All targets were voluntary. Trump, like his cronies who’re bankrolled by the fossil fuel industry, is wilfully ignorant. He’s blindfolded by his 20th century mindset, and his blatant self-interest plays straight into the hands of the fossil fuel industry.
A new incarnation of Merchants of Doubt is now actively trying to slow down the move away from fossil fuels to renewable energy and electrification of transport fleets, with spurious calls designed to raise doubt in the wisdom of moving to those technologies. These include questions about the reliability of energy supply, efficiencies of land use or energy production, the disposal of electronic waste from batteries and solar panels and many others. They neglect to mention that all mankind’s energy needs could be met from arrays of solar panels, covering just 5 percent of the area of the Sahara Desert. I always question the motives of the writers and remind myself that not all web sites are equal. The more reliable ones are maintained by reputable bodies like the World Meteorological Organisation (WMO), the United Nations Environment Programme (UNEP), the Intergovernmental Panel on Climate Change (IPCC) and large science agencies like NASA in the US and the UK’s Met Office. Wikipedia is usually reliable but can be (temporarily) hi-jacked. Of course, there will be new problems to be solved, but all will be more tractable than those from a continuation of fossil fuel burning. New methods will of course be developed to recycle waste.
Even before the development of the Antarctic ozone hole, as well as concerns about chlorine from CFCs, there were already concerns about how emissions of nitrogen oxides (NOx) from the projected fleet of supersonic aircraft flying in the stratosphere might impact ozone. Both NOx and chlorine led to ozone depletion. Which was most important? The theory was still under development.
Despite Farman’s idea - later proved correct - that CFCs were to blame, others speculated that the ozone losses were attributable to increases in NOx associated with the descent of air from higher altitudes in a region of the atmosphere called the “mesosphere” during a period of high Solar activity. Increased levels of NOx do indeed occur at high altitudes during such periods (e.g., during solar proton events – when the concentration of particles from the Sun is hugely amplified). These increased NOx levels can indeed lead to ozone losses at those higher altitudes. But, if this were important for the total column amount of ozone, then there would be an 11-year cycle in Antarctic NOx (and ozone) in phase with the cycle of solar variability, and NOx levels would be elevated compared with other locations. Our subsequent measurements put paid to that theory, showing that any changes in the total column due to solar cycle effects were small.
Nitrous oxide (N2O) has a much longer lifetime in the atmosphere than the other oxides of nitrogen. It’s also known as “laughing” gas for the euphoria it produces when used as a pain killer, but it’s no laughing matter in the atmosphere. It’s the third most important greenhouse gas (after CO2 and CH4). It is currently increasing at the rate of about 3 percent per decade, due mainly to over-use of nitrogenous fertilisers in agriculture. Nitrous oxide is also a source gas for nitrogen dioxide (NO2) in the stratosphere, so in a future atmosphere containing higher concentrations of N2O, higher concentrations of NO2 may consequently be expected in the stratosphere. However, stratospheric temperatures will by then be significantly lower, because global warming at the surface leads to decreases in stratospheric temperature that are twice as large as the increases at Earth’s surface. Therefore, at mid and low latitudes where gas-phase chemistry dominates, the reaction cycles that lead to ozone depletion will run more slowly under a globally warmed climate. But, in polar regions, where heterogeneous chemistry dominates, polar stratospheric clouds will be more prevalent, so the effects on ozone would be more severe.
At the same time, we were becoming less concerned about the oxides of nitrogen from aircraft. Manufacturers had (temporarily) shelved their plans for the proposed fleet of supersonic aircraft flying in the ozone layer. That was for economic rather than environmental reasons. Understanding of chemistry was evolving too. Famous among atmospheric scientists, the “Wuebbles” plot produced by Don Wuebbles, then at Lawrence Livermore Laboratory in California, illustrated that point.
His plot (above) showed that in some periods, depending on our understanding of chemistry at the time, the models predicted that the fleet of aircraft would be good for ozone. In other periods, the model predicted it would be bad: causing ozone depletion. For example, in the late 1970s, the models predicted that the aircraft emissions would have been beneficial for ozone, but CFC emissions would have been disastrous. But by the late 1980s predictions were like those in the mid-1970s. If the fleet of aircraft had transpired, it would indeed have led to ozone depletion.
So the oxides of nitrogen were still potentially important. On my return to New Zealand in 1986, I designed an “improved” ZMR to measure them. A skilled workshop engineer, Case Zwanevald, at DSIR’s Gracefield Laboratory in Lower Hutt, painstakingly built the machine to my specification over a period of several months.
It was shipped down to Lauder to begin its life of productive measurements. Unfortunately, a few seconds after turning it on, I realised that it was not going to work. My design had a critical flaw. The inner radius of the spool that held the magnetic coils was in direct contact with the outer wall of the gas cell. When the a/c current was applied, vibrations to the cell swamped the signal. It was a terminal blunder. The months of work by Case had been wasted. I feel guilty every time I think of it. He retired soon after, and I never had the heart - or courage - to confess my folly.
I justified my decisions to can the project with the knowledge that another newly-developed class of instruments, based on the Michelson Interferometer, had recently been developed to do the same job, and one was to be purchased for use at Lauder. These expensive, wonderful instruments can measure not only nitric oxide, but also any gas of interest, including all of the important greenhouse gases and ozone-depleting substances from the ground. In some cases, they can even measure their altitude distribution.
Around that time, instruments were becoming available to measure the altitude distribution of NO2 from satellite. In 1988, the team at NASA’s Langley Air Force Base asked us to help them unravel a problem with a satellite-based instrument they called “SAGE”, an acronym for Stratospheric Aerosol and Gas Experiment. Our NO2 data from Lauder helped them solve the problem and they went on to develop several more versions of the instrument, SAGE II, SAGE III, and SAGE IV - so far.
The principal investigator there was one Pat McCormick. He delighted in sporting SAGE I and SAGE II personalised number plates on his cars. But one of his staff beat him to the punch and bought the SAGE III plates first. Quite a coup, but I doubt if that decision served his career well. While I was at Langley, another of McCormick’s up-and-coming scientists, Joe Zawodny, introduced me to a new programming language called IDL (short for Interactive Data Language), which had been developed in the USA especially for geophysicists like us. It was a huge boon to data visualisation. Joe visited our lab in 1991 but it wasn’t until a couple of years later, when Ben Liley started to make our data sing and dance to its tune, that it became widely used at Lauder.
But by then our interests had broadened. It wasn’t all about NO2 anymore. International efforts were ramping-up to understand the cause of the Antarctic ozone hole. Scientists from around the world took advantage of Lauder’s relevance and proximity to visit. Some of them established research programmes there that continue to this day.
Large measurement campaigns organised in the USA often involved flights from New Zealand’s Antarctic Centre at Christchurch airport down to Antarctica. So, at Lauder we were close to the action. But the key finding was from a 1987 expedition out of Punta Arenas in South America in (called the AAOE mission), which came up with the definitive evidence that reactions with chlorine were the cause of the problem. A graph from that campaign showed an almost perfect anti-correlation between ozone and chlorine monoxide from measurements undertaken from a high-altitude aircraft flying in the stratosphere between Punta Arenas and Antarctica. The plot became known as the “smoking gun” proving that CFCs were the culprit.
Soon after, every country in the world would sign on to the Montreal Protocol to protect the ozone layer, a landmark agreement that would serve as a standard-bearer for global cooperation.
Next week’s chapter answers the question: why do we care about ozone?