By seven in the morning the sun is hot. The weather has taken a distinct turn for the better. But, with uncertainties over the organization and safety of the expedition, the mood for many of us is not good. Tom goes to great trouble to take Caroline, Gaby, Roman, Steve and I to an incredibly beautiful small beach on the western side of the island which he discovered on earlier explorations.
Big, dark granite rocks contrast with the bright sand. The rocks are as if selected and carved by a sculptor of incredible genius. At one end of the tiny beach a torrent of fresh water pours down. It has dug scoops and spirals into the granite to produce a stone garden that is Zen. Islands and ridges rise in the distance. There can be few places in the world this beautiful. The mountains of Nepal are one.
We snorkel out over the remains of the reef, now almost entirely dead and largely encrusted with algae. Incredible beauty above the water; devastation below. We are swimming over a massive bone yard of dead coral. It all died in the bleaching event of ’98.
Nevertheless, for an inexperienced diver like me [under my belt a cold murky quarry in Leicestershire and a week of marvels in Komodo, Indonesia] the relatively few fish species we do see are enough to set me buzzing and eager to check out what I have seen in A Guide to the Seashores of Eastern Africa and the Western Ocean Indian Islands (edited by Matthew D. Richmond, published by the Swedish Development Agency).
We take a bus tour round Mahe island, home to the majority of the people in this nation smaller in population than Oxford. By African standards, the living standard is very high. The Seychellois have achieved real success in education, at least to secondary level. But the economy is in real trouble.
The currency, the Seychelles Rupee, is reportedly close to crisis as a result. That’s why it has been so difficult for us to obtain so many essential items. Many Seychellois (names withheld) squarely blame the corrupt the government of the President, France Albert Renee.
Good news on our return to Victoria: the Ceres has arrived. It is a broad, powerful boat: single-masted, with a 135 horse power engine and a complement of reliable outboards. Nico is 34, German origin. Very large and lean, extremely intense, burnt a very deep bronze. He does some chartering and has also…traded around Madagascar for a number of years.
Nico has a crew of one, named Willy: a small, tough and clever Madagascan. He has also brought along Alexandrine, Harmut’s Madagascan girlfriend.
Cyclone Hari (not Harry as I previously wrote) has moved West towards Madagascar. The weather over Saya is improving rapidly. We all get drunk.
For a good part of the morning Pete, Frank, Roman, Steve, Gaby and I move the remaining steel for Saya on board the Ceres, using the Eurydice as a ferry. In the sun, with fierce light reflected off the water, moving just half a tonne becomes an exhausting job. ‘Schleppen’ in German.
After lunch I sit with Tom to discuss coral reefs and global warming. He gives a pretty full history, which is partly recorded here. Any errors in this account are my fault.
Tom says: “No one paid much attention to what the upper limit of temperature for corals almost a hundred years ago. Alfred Mayer was studying corals in the Dry Tortugas in Florida. He observed an unusual phenomenon at low tide: corals would turn white, what we would now call ‘bleached’. He hypothesized that this was due to high temperature, and did a series of experiments to test this. He showed that a temperature difference of not more than a few degrees would cause coral bleaching and then death, if the raised temperature was prolonged.
“In 1919 or 1920 Mayer went to Murray [?] Island on the northern-most end of the Great Barrier Reef. He did classic survey and transects, and performed similar temperature tests to those he’d done in Florida. He found that, just as with corals in the Caribbean, the Australian corals had very distinct temperature limits, although he didn’t delineate this very finely.
“In the mid 1920s Maurice Younge led the first Cambridge University expedition to Lowe island on the Great Barrier Reef. Now these guys didn’t dive – they didn’t have the technology. They went to tide pools at low tide to take their photographs. Younge observed that on some occasions the coral would bleach. He showed that this happened when conditions were a lot hotter than normal – for example at mid-day on days of extreme low tides. The gist of what he showed was that at a degree Centigrade or so above normal maximum temperature the corals die.
“There was very little further study of bleaching – or reef science in general – until my father [Thomas Goreau] started work after the war. In 1963 my father was diving in the reefs around Jamaica right after a massive hurricane [‘Flora’] hit. The hurricane brought huge rains to the island. My father found that the bleaching was confined to areas where fresh water was flooding onto the reefs from the swollen rivers.
“We now know that there are many things that will make coral bleach. In addition to water that is too hot or too cold, corals are sensitive to water that is too fresh or is hyper-saline. For example, desalination plants [which produce fresh water for human consumption, and dump large amounts of salt back into the sea] have killed all the coral in parts of the Persian Gulf. It will never come back. Corals will also bleach from too much light and too little, and to various poisons. In other words, it’s a generalized physiological response to any form of stress.
“In every known case until the ‘80s, bleaching was confined to very limited areas that had clearly undergone intense local stress. It was always a transient phenomenon. Then we began to see a completely different pattern.
“In 1983 Peter Glynn, who had worked with my father, was studying coral on the Pacific side of Panama. He saw all the reefs go white and start to die. This was linked to the El Nino of that year –the strongest one on record, which had catastrophic effects on the whole eastern tropical Pacific region, down to Panama and across to the Galapagos Islands. In Peru the fishery was devastated.
“Peter Glynn had just published a magnificent book on the corals of Galapagos. In that year the bleaching was followed by 99% coral mortality on those islands. Elsewhere in the region levels of mortality were almost as high.
“Peter went to a lot of trouble to check other possible factors behind coral death, but became convinced that high sea temperatures were the cause. He pointed out that if global warming came about this would happen a lot more in future.
“Most people’s natural reaction was to say that corals could take anything and bounce back – after all they have been around for millions of years. Global warming was a lot of nonsense. Peter was attacked so viciously regarding his warning about global warming that he decided to lay low, although he’d very clearly made his point in a low key way.
“Another common reaction to Peter Glynn’s findings was to say that there must be something very peculiar about this region because as a general rule corals could not possibly be growing close to their upper limit of temperature tolerance.
“Then in 1987 we saw a second regional-scale bleaching event. This affected large parts of the Caribbean as well as the eastern side of the Pacific. I was in Caribbean in that year, doing a long-term study of coral growth rates. They all began bleaching just as I started my the study. I had no idea why. I had never seen it before on such a scale. It was like snow had fallen on the reef for miles and miles. The difference in temperature above normal was so small that it seemed incredible this could be the cause. I myself didn’t believe it.
“The Association of Marine Laboratories of the Caribbean pulled together [a team to find out what was going on]. This was coordinated by Bert Williams at the University of Puerto Rico and included Ray Hayes, Professor of anatomy at Howard University and myself.
“We found that there was no systematic or regionally calibrated monitoring of temperature going on at any of these labs, except to a limited extent at Puerto Rico. So right away I began measuring temperature when measuring growth rates. I wanted to calibrate the two. For several years I was in the water frequently, measuring temperature.
“We had wide scale bleaching in the Caribbean again in 1989. Peter Glynn had been the first to see region-wide bleaching happen twice. Now I and others had also seen it happen twice, with the difference that this time we had been measuring the temperature threshold at which it happened. I wrote a paper for on this for Nature, again making the link to the dangers of global warming.
“Ray Hayes and I also began to search for other sources of data on temperature. Thanks to real persistence on Ray’s part, we tracked down Jennifer Clarke at NOAA [the US National Oceanic and Atmospheric Association].
“The first satellite that could properly track sea surface temperature continuously went up in 1982. Since then Jennifer had been the one who had taken the raw satellite images and converted them into temperature data. It is a very subtle art. In my view you can’t trust the automated procedure [that has replaced her].
“With the help of Jennifer’s maps, interpolated with data collected by hand I could get time series for the temperature every two days for all around the Caribbean at the times we knew bleaching had happened. [It took until 1990 to get the complete picture together]. I was able to show that at every site there was an unambiguous threshold in the monthly average temperatures [of the hottest months] above which bleaching always happened and below which bleaching never happened. That temperature was about 1 degree C above the average monthly maximum for that site.
“In Jamaica that average maximum in the hottest month was 28.5 C. In Bermuda it was 26 C for the same coral species. In other words it was the increment, not the absolute value that made the difference.
“We decided to publish our findings as a technical bulletin, jointly with NOAA who had provided so much of the data. With our NOAA colleagues we went through intensive critical review. NOAA finally agreed the conclusions were iron clad and must be published. But this was the era of George Bush [senior]. Our paper went to the office of the public relations council – and vanished. They strung us along for a couple years. The paper was done in 1991 but was not published until 1994. We had shown that global warming could endanger a whole ecosystem so they hid it. This was political censorship by the Bush administration.
“By this time we had established the case for the Caribbean very clearly. We decided to look at the Pacific and Indian oceans as well. We knew that those oceans were also affected by bleaching but the reports were very incomplete. I took NOAA global satellite maps and a publication that covered temperature anomalies. I mapped out where bleaching was known to happen and found exactly the same thing as for the Caribbean. I circled those areas and coined the term ‘hot spot’. This work was published in 1994 in Ambio – the first paper to describe hotspots and showed they occurred world wide” [co-authored by Tom Goreau and Ray Hayes]. “That’s why NOAA now has a hotspot site, although without any credit to the authors of the idea.
“We have since refined down the figures for hotspots to more like 0.9 degrees C. An excess of around 2 degrees for one month or one degree for two months is enough to kill corals: mortality is a factor of the duration and extent of the warming.
“I have a compete global database for all coral regions from ‘82 to ‘97 for 250 sites all around the world – every major reef area. That was a lot hard work – they sent me all the raw data in random order!
“It’s clear that some areas are warming upper faster then others. [Moreover], there are strong circulation changes taking place that are not in the climate change models. The models pretty much assume that ocean circulation patterns don’t change. This is a very great weakness because oceans are critical to the transport of massive amounts of heat, and very small changes can have profound effects…But this is ignored on grounds of ‘computational tractability’.
“In some areas the ocean may be stratifying and be unable to mix so frequently. In other areas the opposite will be the case. The odd corollary is that global warming could lead to local cooling in some areas.
“When I did regression analysis on the regional pattern of warming and cooling world wide within the tropical band it coincided exactly with the parts of Al Strong’s work [at NOAA] for the global pattern within tropical band. Only in the tropics is the increase in temperature statistically significant in relation to noise in the data. Outside the tropics the trend is clear but not quite within the 95% [band of probability to make it virtually unambiguous]. Until just the last few years, we saw the warmth being trapped in the tropics. Now it is flooding out rapidly to higher latitudes.
“Global warming will kill coral everywhere expect where upwelling [of cooler waters from the deep ocean] increases. This is not a question of decades or centuries. To be hyper-conservative I would say 5 to 10 years. The reality is a couple of years. Corals will probably survive – as individuals, not as reefs – at the extremes of their range. But the situation is far more frightening than [the so-called mainstream] will admit.
“In the early 90s I got involved with the people working on the UN Framework Convention for Climate Change [UNFCC]. We inserted language into the draft that would require climate change to be limited to the rate at which the most sensitive ecosystems, such as coral reefs, could adapt. These clauses were removed during negotiation.
“The UNFCC failed. It acknowledged that climate change was a concern, and that [a major element of its purpose] was to protect ecosystems: but it did not define and identify properly what those ecosystems were; it did not require that there be monitoring of those ecosystems and climatic damage to them; and it did not require a trigger mechanism for greenhouse gas reductions if such damage be shown.
“I said [at the Earth Summit in Rio in ’92 that the Convention would not protect coral reefs. Later, others like Greenpeace jumped in. But the majority of countries with a coral resource were bought off by the US, which promised them their own special conference – the UN Conference on Sustainable Development of Small Island States. When this actually came about, in 1994, none of the major powers sent delegations of any seniority. The small island nations were ignored once again. They were duped with a shabby trick. It worked.
“Corals will not be the last ecosystem to go [as a result of global warming]. They just happen to be the most sensitive of all to temperature changes and pollution.
“I have nothing to say more on global warming. Others repeat our exact words from that time. But it’s too late now. We have missed the key opportunity. Our coral nurseries are the only thing that will really make a difference now.
“Of course [mineral accretion technology] is a very long way from being the whole answer. Certain species of coral all died even on our structures [in the Maldives during the warming event of ‘98]. In future it may be worse. But people will benefit if in no other way than because [our technique] delivers for fisheries dependent upon corals – as can be seen at Permuteran [in Bali, Indonesia] where fish populations have increased dramatically near our structures.
“People don’t want to believe [in of our technique the benefits to coral] unless they’ve seen it for themselves. Unfortunately, not enough people have seen it. But what else can we do? We are trying to the best we can. What’s pathetic is that what we do is on a trivial scale. We have tried every private funding agency in the US and not one of them is ready to support our work. They are talking about trivial peripheral issues, not what’s really killing the corals.
“[The private and public funding agencies] spend large amounts of money to establish marine parks. Now the marine park people get very angry with me for saying what they are doing is a waste of money. Don’t get me wrong; what they are trying to do is wonderful, but it will not protect corals from global warming.
“You should see the snorkel trail that used to be here [Tom gestures across the water to the marine park beyond the harbour of Victoria]. There is not a single live coral in it! The funders are pouring money into parks that are largely dead. I wish them well but I also wish they would spend money where it would make a real difference.
What about Saya? “Where we went in ‘97 was dominated by massive corals with a lot of diversity. The Shoals of Capricorn study [see bulletin for 28 March] found exactly the opposite: areas dominated by just one species of branching coral. They looked in the wrong places. I suspect there will have been bleaching at Saya in ’98 but, as in the Amaranth Islands, corals may have survived lower down. And in some areas the coral may have been protected by turbidity [reducing light and therefore temperature].
“Saya is a very interesting reef, but a marginal one. It is one of the remotest and probably one of the least disturbed [apart from probable trawling by the Soviets]. If we find it is in good condition we will call for its protection.
“Wolf hopes we could begin building an artificial island for a community that uses renewable energy and sustains itself from the sea. This could be a base for scientific research and monitoring. And that’s great. A place like that should be protected; it shouldn’t been raped.
“It is within the evolutionary capacity of corals to deal with climate change but not within their behavioural or physiological capacity to deal with it. The reefs we have today are a survival from the ice ages.
“Here in Seychelles around 95% of the corals were acropora before the bleaching event. Now these are all gone. Only the porites, the toughest of corals, are left. They are the last to die. This is exactly what you find in the geological record for the Mediterranean, the original centre of evolution for modern reef coral.
Does the loss of corals matter economically? “I think most of the work done on the economics of reefs is bogus. They have very fancy names which I luckily manage to forget - nonsense like contingent valuation, or valuation based upon financial damages for reef destruction awarded by some judge who knows nothing at all about reefs.
“A student of mine did some work on this. We estimated reasonable, conservative values for tourism in 40 to 60 countries. We got figures in the range of thousands of dollars per kilometre of fringing reef. Of course it’s important to account for the fact that in smaller countries there is much less retention of the revenues locally.
“For fisheries, we tried to take account of the fact that many fishermen don’t record a large part of their catch for various reasons and that FAO figures often don’t take account of fish consumed locally [as opposed to for export]. Our results, erring on the side of caution, were tens to hundreds of thousands of dollars per kilometre of reef.
“We didn’t bother with ideas of how you attribute an economic value to the concept of biodiversity. For me that is dishonest, ridiculous, obscene. So the third area for which we calculated the economic value of reefs is in their role as shore protection. A replacement artificial reef made of concrete will cost you an average of fifteen million dollars per kilometre.
The figure is applicable round the world with only minor variation. And this is expenditure that will recur repeatedly as what is built using conventional methods [i.e. without mineral accretion technology] will have to be continually repaired. Tens of thousands of kilometres of seawall will be needed as coral reefs fall apart and seas become more agitated as a result of global warming. So the value of reefs as coastal protection dwarfs tourism and fisheries”.
After this conversation, we take a break. In the evening, the whole expedition team parties on the Ceres. Alexandrine makes a phenomenally good beef curry. The rum is Malagasy: smooth with a hint of vanilla. The general mood is excellent. I chat to Nico, who is not nearly as scary as he looks, and also have a good talk with Pete Lucas. Their words remind me that sailors seek above all sublime beauty and freedom within awareness of the awful power of nature (this sounds pretentious when I write it down but it’s true).
Departure is set for tomorrow morning. The seas towards Saya look calm.
Caspar Henderson
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