A Life Underwater

by Charlie Veron

  When I did finally walk out of AIMS’s front door for the last time, on a sunny afternoon in July 2007, I had cause to ponder. I’d been there when every other staff member first arrived. Throughout most of that time AIMS had been good at send-offs, giving people the opportunity to say things they thought should be said and spreading a little warmth around. Most departing staff were given a pretty piece of coral in a perspex box with a brass label; it had become a tradition. Thus armed, I had given farewell speeches on behalf of AIMS to about half its departing chairmen, most of its directors, and I don’t know how many other staff of all descriptions. It was something I enjoyed.

  The day I left, I waved to Jim the gardener on his tractor, got into my car and drove off without so much as a farewell cup of tea. I missed the opportunity to thank all those who’d helped me over the years, especially the support staff, the people behind the scenes. They never seemed to get a mention when someone else gave a speech, yet they were the backbone of the institute as far as I was concerned.

  I left because bureaucrats had won and AIMS had become just a building. My ignominious departure was not a personal rejection. Most of the old guard departed around the same time, and with a similar lack of grace. Some were more or less fired, others were asked to stay on and declined. For my part, I had no intention of working in a place where bean counters and an electronic key to doors controlled my life.

  The saddest part was that although the more experienced scientists learned how to put up with it, or found another job, beginners seemed to think it was normal. Normal it might have become; necessary or beneficial it certainly wasn’t. I can’t think of a better way of killing off the creativity of a creative person than telling them what to work on, where to work, and when to work. People who do their job well need to be left to get on with it.

  I pause here to emphasise this because of its importance in today’s wider world. At a council meeting in 1995 the chairman, Ray Steedman, announced that he wanted me to produce a book about the institute’s first twenty-five years. ‘Warts and all,’ he said. AIMS: The First Twenty-five Years was published in 1998, with historian Peter Bell the principal author and me the editor. In the introduction I wrote: ‘AIMS is what it is because of close links among the people who work here. AIMS is isolated and has been a frontier organisation in many ways. It has always been full of prima donnas, factions, arguments, workaholics, sloppy dress, self-defensiveness, general infighting and non-hierarchical cooperation. Visitors in suits come from afar – mostly Canberra – and frown on all this and mutter about ‘responsibility’ and ‘accountability’. To which the staff can justly reply that our culture, despite their efforts, is alive and well. And at the end of the day, where else can you find a track record of so much achievement that is real? We have long been, and still are, doing it our way – and curiously enough this tends to keep us ahead of the game.’

  Less than a decade on, that atmosphere had gone and with it the creative zeal of the institute. It had been the place for me for a long time, but it was no longer. On my return from France the place had the air of a prison, with the bars of bureaucracy at every door.

  Reefs in time

  The interlinking of many fields of science that I began in France continued on my return to Australia, finally culminating in A Reef in Time, published in 2008. This book delved into how and why reefs have changed over all time scales and what this predicts for the future. A big part of that delving concerned reef environments.

  When you think about it, coral reefs are extraordinary. They have evolved to live and thrive at a perpetually changing interface of land, sea and air. Compared to the relative constancy of fully terrestrial or fully marine habitats, the coastal fringe is exceptionally forbidding, and yet over hundreds of millions of years corals have made it their own. Their success can be attributed to the control they impose on their environment courtesy of their tight symbiosis with algae. This relationship provides the energy needed to build their three-dimensional matrices of stone ‘trees’ that are homes for the herbivores that keep seaweed in check.

  There is a downside, though.

  To cope with the physical ravages of their environment, and to keep their symbioses in order, corals live on a knife edge. They and the reefs they build go through never-ending boom-and-bust cycles. The booms occur when the sea level is mostly constant and atmospheric carbon dioxide levels are low; the bust conditions are the opposite. The role of sea level change is rather obvious: reefs are left high and dry when the level falls and they can die from lack of sunlight when it rises; it’s a matter of catch up or die in the latter. (I will return to this subject below.)

  Carbon dioxide, a gas rarer than argon, is critical for life on Earth. It is the essential ingredient for photosynthesis in all green plants and it’s also essential for keeping our planet warm: if we didn’t have it our oceans would freeze over and life as we know it could not exist. The mechanism involved has been known for two centuries: carbon dioxide is transparent to the short wavelengths of sunlight and so lets the warmth of the sun in during the day but acts to block this warmth from being re-radiated out at night, as that involves long wavelengths. Moreover, carbon dioxide is the fast-acting currency of the carbon cycle, transferring carbon between living creatures, rocks and air, and around again. All this makes it the controller of a strange mixture of life-giving properties of our planet, regulating Earth’s temperature and being the major player in the chemistry of Nature’s cradle, the oceans.

  This is the background I painted before turning to mass bleaching, one of the two target syntheses of the book.

  Mass bleaching is now a permanent fixture of the ecology of all coral reefs. At first it was restricted to El Niño years – the natural weather cycles that usually come every four to seven years and bring abnormally high temperatures to reefs throughout the tropical and subtropical world. It wasn’t until 1998 that coral biologist Ove Hoegh-Guldberg put forward a hypothesis about how mass bleaching occurred, one that some scientists thought implausible when he first came out with it.

  For hundreds of thousands of years, corals and their algae have lived together in symbiotic harmony. What Ove discovered is that if corals are subjected to too much temperature and light, their algae go into overdrive, producing too much oxygen, some of which remains as free radicals that damage their host cells. But corals can counter this by controlling the number of algae in their tissues. Most biologists believe they do this by expelling the algae, but it’s more likely that they slough off the affected cell layer and replace it with a new layer that has no algae. Either way, the problem is that zooxanthellate corals cannot live without their zooxanthellae, and if they get free of all of them they die. It’s all rather suicidal, and now corals are suffering the consequences, because they live in a world where temperatures increasingly peak above their precisely evolved limits of tolerance.

  Not all mass bleaching is lethal. Sometimes enough algae remain to allow the coral to recuperate, but if no algae remain, death usually follows within months. Seeing entire coral communities turn white is a gut-wrenching sight, especially as it’s not just the corals that die, but also most other animals in the community created by the coral, paving the way for a seaweed or slime takeover.

  With the reality of reefs dying en masse, I wanted to estimate the possible flow-on effects this would have for all marine life. This was prompted by the geological record, which suggested that the demise of reefs gives early warning of a global environmental collapse, even a mass extinction. Evidence for this comes from several quarters, including the links between carbon dioxide and the carbonates that reefs are made of, and the sensitivity of corals to ocean carbonate chemistry. I tried, unsuccessfully in the end, to rope others into helping me to estimate how much marine life would be affected by a complete collapse of coral reefs, but the job was too big and there was not, and still isn’t, enough scientific knowledge about our marine life to draw on. Taking this subject as far as we could, I was persuaded
that about a third of all marine animals are dependent on reefs during at least one stage of their life cycle. If this is true, then the collapse of the world’s reefs would indeed trigger an ecological collapse of our oceans. The geological record, full of suppositions though it is, clearly shows that this has happened many times during our own era (the past 65 million years), and I now felt I had a good case for proposing that we are creating conditions for a re-run. One of many re-runs though it would be, the next will be different because we humans will be among the victims. Will we be prepared? Of course we won’t.

  Coal, the stuff that once powered the Industrial Revolution, is now powering climate change. This prophetic excerpt from a 1912 New Zealand newspaper speaks volumes, yet we are still mining coal with reckless abandon.

  I turned to sea level rise. As I continued with my studies this made a welcome change from being so doomy and gloomy. It had been proposed in many quarters that sea level rise would destroy our reefs, but those who argue this should look at the rate of rise after the last ice age (up to 1.5 metres per century). That was much faster than is likely to occur in our modern world of high sea levels, short of a melting Antarctica, and reefs coped with that rate well enough. What sea level rise will do is lead to the shifting or removal of the colourful zonation patterns most reefs now have. However, seen in the context of geological time, these patterns are abnormal, brought about by the unusually stable sea level we have enjoyed for the past ten thousand years or so.

  The final target subject of A Reef in Time was ocean acidification, which is not an aspect of climate change although it has the same cause: carbon dioxide. Of all the syntheses I made in that book, those delving into the geological past were the most challenging because I constantly found myself in uncharted territory. But I could not let the subject go; it’s critically important.

  It’s quite a climb to the very top of the highest Devonian reef of the Canning Basin, near the coast of north-western Australia, because the limestone, looking like a giant cheese grater, has a karst surface carved into ridges so sharp that even a goanna would be well advised to tiptoe carefully. This reef has a spiritual feel about it. It’s so old that its years number as many as there are metres to the moon, yet 360 million years ago it was decimated, along with every other reef in the world, and they all stayed that way, home only to microbes, for more millions of years. What could have caused that? Ocean acidification and associated oxygen depletion (anoxia) from carbon dioxide could. Certainly, not all ocean catastrophes in the ancient world can be blamed on carbon dioxide, but in most cases I have searched in vain for alternative explanations, and I don’t know why the role of carbon dioxide wasn’t apparent to geologists long ago. The geological past has shown us many times over that the Earth has enormous reserves of carbon that can be converted into carbon dioxide and its chemical associates via a multitude of biological and geological pathways.

  The chemistry of carbon dioxide when dissolved in seawater is generally understood and has been for a long time, although it is not straightforward because it is greatly affected by its concentration in the atmosphere as well as the temperature of the ocean. Like the gas in a bottle of soda water taken from a fridge and left in the sun, it does not stay dissolved when warmed. However, when it is dissolved it forms carbonic acid and that’s the problem. Our oceans can never actually become acid – with a pH of less than 7 – there’s not remotely enough acid on Earth to do that, but carbonic acid does make the surface of the ocean less alkaline, which increases the solubility of calcium carbonate, especially a form of it called aragonite, the stuff coral skeletons are made of.41

  Corals are good at countering this, but as seawater gets less alkaline – meaning less super-saturated with carbonate, even slightly less – coral larvae will struggle to lay down the fine cementing layer that they use to attach themselves to rock, and if they do start growing, their skeletons will become brittle and then may cease to grow altogether. The bottom line is that corals will not grow in the seawater that will exist by the end of this century at the present rate of carbon dioxide build-up.

  Devonian reef, Canning Basin, Western Australia.

  When writing A Reef in Time I had to struggle to describe ocean acidification, because the whole process is easily shown by simple equations but not so easily expressed in words. ‘No equations,’ my editor insisted. I don’t think most of those who read my book would agree with that, but the book did carry the message, at least I hope so.

  The year the book was published, and perhaps because of it, the Nature Conservancy held a workshop in Honolulu about the effects of ocean acidification on reefs. It was attended by Dick Feely, an expert on ocean carbonate chemistry whom I’d not met but knew well from his publications. I had many questions for him, but before I had a chance to ask any he said he wanted to talk to me about my book. I assumed I had gone wrong somewhere, but the following day Dick said that when he’d started reading he couldn’t stop, and had read on all through the night. ‘And the next day I started reading it all over again!’ I felt flattered, but the point he was making was that, as a carbonate specialist, he hadn’t realised the many ramifications of the subject. Ocean acidification is indeed seen in the geological record everywhere, and in coral physiology and in reef ecology. And I believe it will soon be a part of human history.

  The cause of the mass extinction that finished off the dinosaurs is the most debated subject in the history of geology, yet curiously nobody recognised the role that ocean acidification might have played. As with so many sciences, all it needed was a little lateral thinking. Now acidification is taken much more seriously. It doesn’t have the many complexities of climate change and so it receives much less coverage in the scientific literature. It is also less immediate as it won’t be catastrophically affecting all the oceans for decades to come. Nevertheless, its consequences are irreversible on time scales far longer than those of climate change.

  I fear that ocean acidification will be the ultimate evil of the Anthropocene – the only geological interval created by living organisms, us – and the primary cause of a mass extinction in the not too distant future.

  One morning in June 2009 I had a phone call from a man who introduced himself as Paul Pearce-Kelly and said he was from the Zoological Society of London. He wanted to talk to me about A Reef in Time.

  ‘Sure, Paul, what do you want to know?’

  ‘I mean I want to come to Townsville to see you about it.’

  ‘Oh. When?’

  ‘Next week.’

  ‘From London?’

  ‘Yes.’

  Paul certainly kept a tight schedule. The day after he arrived at Rivendell he was off somewhere else, having left me surprised by one of his questions. ‘Charlie, what would you say if I arranged for an emergency meeting at the Royal Society, had Sir David Attenborough chair it, and had your talk streamed around the world?’

  This guy’s a nutter.

  ‘That’d be nice, Paul.’

  A few weeks later he phoned me again. ‘It’s all arranged for July the sixth,’ he said. ‘David’s happy to chair it. We’ll have a conference beforehand. He’ll chair that too. What do you want to call your talk?’

  ‘Really? Um, how about “Is the Great Barrier Reef on Death Row?”’ I was thinking of Mary’s younger brother Clive, a lawyer who’d had spectacular success stopping Americans from executing their own.

  ‘Good,’ said Paul. ‘We’ve got a lot to talk about. I’ve booked you and Mary in at the zoo. They’ve got a nice flat there. Come as soon as you can. It’s interesting to be with the animals when everybody else has gone home.’

  On arriving at the zoo a few weeks later, Mary and I discovered that Paul, far from being nuts, was a ball of energy, self-effacing to a fault, and totally committed to conservation. The Great Barrier Reef Marine Park Authority had helped build a rather slick PowerPoint presentation for me. All that was needed was for me to write some introductory notes about myself, as requested by the
Royal Society, so that Sir David could introduce me. I did as asked, omitting mention of my first visit there, after the Stoddart expedition! But I needn’t have bothered – Sir David gave me his own introduction, and a generous personal one it was.

  On the morning of my talk there was a large meeting of climate change and reef scientists at the Royal Society, with much of the debate being about what level of atmospheric carbon dioxide would give corals optimal environmental conditions. These views were subsequently published in a much-cited article, but at the time I said as little as possible as I had a threatening throat infection and was in imminent danger of losing my voice.42 Fortunately that didn’t happen: my presentation lasted an hour and a half, as arranged, and was followed by an hour and a half of questions, which only ended because the master of ceremonies called it quits. The conference, my talk and the questions had taken six hours; I was astonished at Sir David’s stamina, as by then he was over eighty.

  Some scientists thought my predictions about future carbon dioxide levels were overly pessimistic: they were at the extreme end of the Intergovernmental Panel on Climate Change predictions. Now, nearly a decade on, one slide from my talk gets aired by the occasional investigative journalist. It was made from data I borrowed from oil industry reports and publications, and it said that by 2015 we would have 400 parts per million of atmospheric carbon dioxide (we did). I extrapolated that this would cause major weather events (which happened), and severe bleaching, mainly during El Niño cycles (which also happened). This makes a clean rebuff for those denialists who claim that scientists make it all up, or (as I was sometimes accused) exaggerate. There is much to be said for such reality checks.

  Naturally, I wondered how much difference my book, this symposium, and the spreading of what I had to say would make. For a long time, it seemed not much, but I later had cause to be more positive. As months turned into years I began to appear in more and more documentaries and interviews. I had made the effort to understand the many sciences involved with climate change and have been able to put that understanding to good effect.