Climate Change Shows No Barrier Reef Is an Island: Iain McCalman

Oct. 12 (Bloomberg) -- One of the saddest byproducts of Australia’s current political squabbling over climate change is the way the Great Barrier Reef, the world’s largest living organism, has become caught in the crossfire. It wasn’t always so.

In 2001, I sailed on a replica of James Cook’s ship, Endeavour, under simulated 18th-century conditions through a sizable chunk of the reef’s more than 2,000-kilometer (1,243-mile) length. We were re-enacting for television the most testing stretches of Cook’s first voyage to Australia in 1770.

He had likened the experience to being trapped in an “insane labyrinth,” where death by shipwreck and drowning, or by starvation and native spears seemed inevitable. We, of course, had no such fears. Since Cook’s time, the harsh connotations of this “wilderness” have changed irrevocably. Once a hell, it is now a A$3 billion ($2.9 billion) tourist mecca, marine park, ecological wonder, and wealthy urban and agricultural region.

Our 40-volunteer crew was a mixed lot in every way. There were Australians, Americans, Britons and New Zealanders; men and women; young and old; conservationists and developers; scientists and artists. We argued often, yet were always united by our awe of the environment around us.

The warm coral-filled waters of the Barrier Reef lagoon, studded with sandy cays and wooded volcanic islands, seemed unimaginably beautiful and precious. The Australians on board -- black and white -- found the reef a source of intense collective identity and pride, and fellow shipmates of all nationalities shared our admiration of this World Heritage Marine Park intended for the benefit of all.

Save the Reef

We were beneficiaries of one of the fiercest and most protracted popular struggles of recent Australian history, the Save the Reef campaign of the late 1960s and ‘70s.

Over this period, a populist Queensland premier, Joh Bjelke-Petersen, had challenged successive federal governments and conservationist bodies by his aggressive economic development of the reef. He sanctioned the crushing of reef corals for agricultural fertilizer, granted sweeping foreign rights for oil and mineral exploitation, and encouraged the building of environmentally reckless tourist resorts.

The ensuing political struggle was led by the rare combination of a poet, Judith Wright; an artist, John Busst; and a scientist, Len Webb. Together they managed to mobilize citizens of all political stripes. They also persuaded successive Liberal and Labor governments to combine in the cause of reef protection and to challenge the Queensland premier in the High Court on the issue of federal versus state jurisdiction.

The culmination of the campaign saw the declaration of the Great Barrier Reef World Heritage Area in October 1981. It instantiated a statutory compromise of shared federal and state custodianship over an area of mixed economic exploitation and wildlife conservation that was roughly the size of the U.K. and Ireland: all of it under the day-to-day governance of the Great Barrier Reef Marine Park Authority. Despite periodic strains between conflicting interests within the authority’s jurisdiction, few would dispute that it has nurtured one of the best protected and managed marine parks in the world.

Just 20 years later, there were growing signs, however, that larger environmental forces could disinherit us all. In 2001, a biologist showed some of us from the Endeavour evidence of a new outbreak of mass coral bleaching comparable to the first recorded incidence in 1997-98.

Up to that time, scientific concern about the Barrier Reef had centered on the damage being inflicted by voracious coral-eating crown-of-thorns starfish, but that problem, while still unsolved, has paled beside the scale of destruction of these bleaching events.

El Nino’s Effect

During El Nino weather cycles, when the temperature in the Pacific is already unusually high, seawater heated further by greenhouse-gas-induced global warming is being pulsed onto the delicate reef-growing corals. It’s a few degrees hotter than the usual optimum of 27 degrees Celsius (81 degrees Fahrenheit) for the single-celled algae, which live in the corals’ tissues and provide their color and food through photosynthesis with sunlight. So the algae begin producing toxic levels of oxygen. The corals must then expel their algae or die. Stark white skeletons remain. Although recovery is possible when water temperatures return to normal, the frequency and intensity of outbreaks are hampering this.

More recently, scientists have detected a still graver threat to the reef. John Veron, a former chief scientist of the Australian Institute of Marine Science and a winner of the Royal Society’s Darwin Medal, has written an ominously titled book, “A Reef in Time: The Great Barrier Reef From Beginning to End,” which suggests that long-term destructive forces are already under way.

Again, the culprit is greenhouse gases, now pervading the atmosphere at unprecedented rates and levels. Already the world’s oceans, normally buffers to carbon dioxide, are losing their capacity to absorb and chemically balance the gas. Eventually -- possibly within 50 years -- they will acidify. Seawater will then work to neutralize this acidic effect by dissolving numerous forms of calcium carbonate prevalent in the marine environment, like a giant antacid.

Among the first organisms to be affected will be reef corals. Their calcium or aragonite skeletons will cease growing or become too brittle to resist the eroding effects of waves. Corals, of course, aren’t the only marine organisms implicated: Krill, a crucial fabric of the marine food web, are also under threat. We could ultimately face something like the K-T mass extinctions of 65 million years ago, which put an end to coral reefs and related marine organisms for millions of years.

If Veron is right, and many scientists seem to think he is, then the Great Barrier Reef could die within a generation or two. If we can’t agree to commit to the reduction of greenhouses gases needed -- and there is every sign we can’t -- then perhaps we should be thinking about how to adapt to this tremendous change? If the peoples of the Amazon must imagine living without their rainforest, should we Australians be learning to live without our reef?

(Iain McCalman, a professor of history at the University of Sydney and the author of “Darwin’s Armada,” is a Bloomberg View columnist. The opinions expressed are his own.)

To contact the writer of this column: Iain McCalman in Sydney at

To contact the editor responsible for this article: Stacey Shick at

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