The ‘underwater rivers’ of Mexico


These amazing photographs were taken by the Russian underwater photographer Anatoly Beloshchin.


In his own words: We are 30 meters deep, fresh water, then 60 meters deep – salty water and under me I see a river, island and fallen leaves… Actually, the river, which you can see, is a layer of hydrogen sulphide.”


Check out his website ( for some truely great underwater photography.


Great Barrier Reef survival “requires 25% CO2 cut”


Reuters, November 16th 2009

Australia’s Great Barrier Reef has only a 50 percent chance of survival if global CO2 emissions are not reduced at least 25 percent by 2020, a coalition of Australia’s top reef and climate scientists said on Tuesday.

The 13 scientists said even deeper cuts of up to 90 percent by 2050 would necessary if the reef was to survive future coral bleaching and coral death caused by rising ocean temperatures.

“We’ve seen the evidence with our own eyes. Climate change is already impacting the Great Barrier Reef,” Terry Hughes, director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, said in a briefing to Australian MPs on Tuesday.

Australia, one of the world’s biggest CO2 emitters per capita, has only pledged to cut its emissions by five percent from 2000 levels by 2020.

It has said it would go further, with a 25 percent cut, if a tough international climate agreement is reached at U.N. climate talks in Copenhagen in December, but this is looking increasingly unlikely with legally binding targets now off the agenda.

“This is our Great Barrier Reef. If Australia doesn’t show leadership by reducing emissions to save the reef, who will?” asked scientist Ken Baldwin, in calling for Australia to lead the way in cutting emissions.

But the Australian government is struggling to have a hostile Senate pass its planned emission trading scheme. A final vote is expected next week.

The World Heritage-protected Great Barrier Reef sprawls for more than 345,000 square km (133,000 sq miles) off Australia’s east coast and can be seen from space.

The Australian scientists said more than 100 nations had endorsed a goal of limiting average global warming to no more than two degrees Celsius above pre-industrial temperatures, but even that rise would endanger coral reefs.

The scientists said global warming was already threatening the economic value of the Great Barrier Reef which contributes A$5.4 billion to the Australian economy each year from fishing, recreational usage and tourism.

The U.N. Intergovernmental Panel on Climate Change has concluded that the Great Barrier Reef could be “functionally extinct” within decades, with deadly coral bleaching likely to be an annual occurrence by 2030.

Bleaching occurs when the tiny plant-like coral organisms die, often because of higher temperatures, and leave behind only a white limestone reef skeleton

The Last of the Bluefin Tuna?

I’ve often wondered whether people who eat tuna from a can have any idea what a tuna fish actually looks like? How does a can of tuna still cost less than a dollar? Mainly because the average tin of tuna comes from smaller and less tasty species (usually albacore or skipjack at roughly $25 per pound), which are still plentiful* in the oceans as they require less resources to survive and reproduce. In contrast, the closely related southern bluefin tuna commands upwards of $350 per pound, yet is IUCN listed as ‘critically endangered’. With commercial extinction looming on the horizon, who will be the last person to eat a southern bluefin?

Bluefins are amazing animals. They can live for 40 years and attain weights of 1,600 pounds, yet they blast through the water at speeds in excess of 60 miles per hour. In other respects, they have everything going against them. The tuna grow slowly, and young females lay a only fraction the number of eggs that older ones do. They only have two spawning grounds, one in the Gulf of Mexico and one in the Mediterranean Sea, and when they are on them, tuna form tight schools, making them easy to catch.

Should bluefin disappear, much of the blame should go to an organization called the International Commission for the Conservation of Atlantic Tunas (ICCAT), although Carl Safina of the Blue Ocean Institute gave what some consider a more appropriate name, the International Conspiracy to Catch All Tuna. There are now only about 34,000 tuna swimming in the entire western Atlantic, down 82 percent from 1960s levels when the commission started “managing” the fishery.

“Looking at the science, there’s nothing else that makes any sense,” she said. “The current quota is driving the species to commercial extinction.”

Not that ICCAT ever pays much attention to science. “Last year ICCAT’s scientists said that the quota should be no higher than 15,000 metric tons,” said Lieberman. “So they went with 23,000 tons. In reality, with overfishing and illegal fishing, what they actually took is much higher. You can pretty much figure that it was double the quota. What we’re calling for is to suspend the fishery. Let it recover, and then you can go back to fishing. But there’s tremendous opposition, particularly from the European Union, to cutting anything.” (Read More)

* For albacore tuna, North Pacific biomass is 7% above the long-term average biomass for the exploitable stocks. South Pacific biomass is 33% above the biomass needed to support maximum sustainable yield

Climate change is a “left-wing conspiracy to de-industrialise the world”


Over the past few weeks, the debate in climate change has reached new levels of ridicule – such as this comment by Senator Nick Minchin:

”For the extreme left it provides the opportunity to do what they’ve always wanted to do – to sort of de-industrialise the Western world,” he said. ”The collapse of communism was a disaster for the left and really they embraced environmentalism as their new religion. For years the left internationally have been very successful in exploiting people’s innate fears about global warming and climate change.” (Read More)

In which case, as part of the IPCC review process, I must too be part of this ongoing conspiracy to fill the void left by communism! Is the IPCC really at the heart of a massive conspiracy theory?

A letter writer to a newspaper recently pleaded for guidance on how to get the facts about whether there is human-induced global warming. But the writer added emphatically that he did not want to read reports of the Intergovernmental Panel on Climate Change (IPCC) because he wanted independent and reliable information.

Now, it could just be me, but I would have thought that the world’s most comprehensive assessment and review of climate science by thousands of international experts should probably be the first port of call when searching for facts.

So is the IPCC really that kooky? Have thousands of participating scientists from around the world who’ve contributed to four IPCC reports since 1990 duped the world with hidden agendas and manipulated science? Have they all got it wrong? (Read more)

It’s interesting to see how this meme has developed in recent times, and probably highlights the fact that climate change is now more about effective communication and politics as opposed to ‘proving’ science.

Supermodels take it off for climate change


In the run up to Copenhagen even supermodels are jumping into the fray.   There is a new viral video (700,000 views in just over 10 days) in which some supermodels “strip for climate change” on behalf of Bill McKibben‘s new outfit  How exactly this video will assist in mitigating greenhouse gas emissions or in getting us back to 350 ppm is not entirely clear.  (but I suppose the same could be said about our blog)


Ove and Charlie Veron discussed the importance of getting back to 350 ppm here;  The coral reef crisis: The critical importance of <350 ppm CO2

The utility and some of the nuances of the 350 concept, e.g., how soon do we need to get back there,  have become a bit controversial within certain AGW circles.  Witness this dust up among AGW blogosphere titans Bill McKibben, Andrew Revkin and Gavin  Schmidt (click on the comments and read comments #3-5).  Also see this view of the idea and campaign by Dr. Ray Pierrehumbert, a University of Chicago climate scientist (and fearless debunker of the rubbish about climate change being peddled by Steve Levitt):

Hansen’s specific reasoning behind 350 was based largely on an estimate of the CO2 level when Antarctic glaciation started, plus a bit of margin of safety thrown in. There is a lot of uncertainty regarding that CO2 level, but it is certainly an interesting line of thinking. One needs to recognize,though, that this specific argument for 350 involves relatively slow climate responses. It is unlikely that Antarctica would deglaciate if we exceeded 350 for just a decade or two. So, you have a bit of wiggle room on the overshoot, so long as the CO2 doesn’t stay above 350 for several hundred years (the precise duration where you get worried being contingent on aspects of the response time of ice sheets that are still poorly understood).

Now, the problem is the slow recovery time of atmospheric CO2 after you stop burning fossil fuels. But, what is certain is that if we go to 600 or 700, the CO2 could easily remain over 350 for a thousand years, which gives a long time for bad stuff to happen. So, the “350” goal may still be attainable if it is interpreted as meaning we have to keep the CO2 300 years out (say) from exceeding this value. – Dr. Ray Pierrehumbert via a comment on Dot Earth

Update (15/11/09); a reader emailed to ask how the “dust up” mentioned above could be found.  It can be seen in the DotEarth story on the 350 movement (note the mildly critical comments by Gavin Schmidt, Andrew Revkin (the author), and Ray Pierrehumbert (above) and in articles on the 350 idea on why how we get back to 350 matters and on the Hansen paper much of this movement is based on on the Real Climate web site, and in the comments section of one of these articles.  To make it really easy, ill paste some of the comments below:

I’d hoped to retain that great final line, but in the eternal space crunch, it got dropped.

The vital question, I’m told repeatedly by specialists in the non-science arenas you list (economics, technological change, politics), is what policies have the best shot of producing a peak and decline that limits climate risks as delineated by the science.

And most of those curves are quite similar no matter what end point is chosen, given the change required just to stablize at ANY concentration in a world heading toward 9 billion people seeking decent lives.

A couple of useful additional perspectives that didn’t fit in print were offered by Rajendra Pachauri of the IPCC (who endorsed the 350 campaign):

“We are dealing with a dynamic system. Hence, what would really be relevant is the trajectory of concentration levels and therefore emission trajectories. The 350 number has some appeal, because it would to some extent determine the peaking period and the rate of decline. Of course 350 by itself provides no solution. It would merely be the end point of a trajectory which theoretically can have infinite alternatives.”

And Mike Hulme, the British climate maven who wrote “Why We Disagree About Climate Change”:

“I never quite know what targets like 400, 350 or 280 mean…. If we mean stabilise back at 280 by 2200, say, then we can pump a lot of CO2 in the meantime, before some really good carbon scrubbing technologies in the 22nd century come along. Same argument actually for 280 by 2100 if you’re a technology optimist. So really if one wants to deal in long-term numbers then talk either about future C budgets (how many gigatons are you going to allow), or else set the peak concentration and by when. My guess is that for CO2 we will hit 500ppm sometime this century (harder to guess what CO2-equiv will be). On what to aim for – I wouldn’t play politics will long-term numbers: far too easy for them to be hijacked and used for all sorts of dubious reasons and causes. Much better is to focus on near-term goals (2015, 2020) and to break them down into manageable sectors (e.g. aviation, municipalities, aluminium sector, etc.). The rhetoric of global long-term targets raises the illusion that we can govern globally over the long-haul (the illusion of Copenhagen) – and we can’t.”

Many thanks to Gavin for his clarification, and for his work (and everyone else’s at RC) over the years. For whatever reason Andy chose to paint the 350 effort as unlikely in his story, but it was reported the day before we actually showed you could mobilize millions of people in 5200 events in 181 countries in what the press is calling ‘the mose widespread day of political action in the planet’s history,’ all around a scientific data point. I think tht should be heartening to all.

The biggest point the number gets across, i think, is that climate change is not some future threat but a present crisis. If you have a moment, I recommend browsing through the photos we’ve got up at (a tiny subset of the 21,000 now in our flickr photostream) to get a sense of the people who are waking up to this reality.

thanks to all who participated Saturday

Andy Revkin says:

27 October 2009 at 2:31 PM

Just one last thought here, upon reading Bill’s comment.

There were two things to report on (and my reporting continued through the actual day of action):

1) The amazing coordinated globe-spanning mosaic of actions
2) the basis for the focal point of that action.

On the first, there’s no question an epic effort was carried off with astonishing scope and skill.
On the second, there remain large, substantive and vital questions. As I said in a comment response somewhere on my blog, a keystone question is 350 by when? As Pachauri and others explained, 350 ppm on its own is kind of like judging a car’s mileage by “miles” without the “per hour.”

My story had to examine both the news and the context. We’ve been pilloried in the past for simply reporting what folks are saying without examining the evidence and argument. I’m not drawing ANY comparisons at all, but examples that come to mind are when a president pumps up the WMD threat, or when candidates rattle off jargon like “clean coal.”

Who has the nuttiest national politicians?


I had thought that nobody made wacky national politicians like we do here in the US (see Michelle Bachman).  But Kevin Rudd’s speech on climate change last Friday included some jaw dropping and hilarious quotes from denier and on-the-fence Australian politicians about climate change.

Would-be Liberal leader Tony Abbott said in July this year that “the science … is contentious to say the least”. (27 July 2009)

Liberal Senator Cory Bernardi said:
“I remain unconvinced about the need for an ETS given that carbon dioxide is vital for life on earth”.

Liberal Senator Alan Eggleston said:
“Levels of carbon dioxide have risen in the world, but whether or not this is the sole cause or just a contributor to climate change is, I think, unanswered.”
(11 AUGUST 2009)

Excuse me, but does “liberal” mean something different on the bottom of the world, like maybe, “conservative” or “totally uninformed”?   Is Australia like, opposite world?  I may need to consult my travel guide before I move there in January.

Liberal Senate leader Nick Minchin said this year:
“CO2 is not by any stretch of the imagination a pollutant… This whole extraordinary scheme is based on the as yet unproven assertion that anthropogenic emissions of CO2 are the main driver of global warming.”
(11 AUGUST 2009)

Alternative Liberal leader Joe Hockey – who knows better – has been drawn into the same sort of doublespeak, remarking on the Today Show in August:
“Look, climate change is real Karl, you know whether it is made by human beings or not that is open to dispute.”
(12 AUGUST 2009)

Even the leader of the Opposition, once Minister for the Environment, Malcolm Turnbull, has flirted with this doublespeak, telling Alan Jones on 2GB:
“I think most people have at least some doubts about the science.”
(19 JUNE 2009)

OK.  That is, I admit, an impressive showing.  But we have some nuts leading our government as well. Or as Kevin Rudd mildly put it “Climate sceptics are also a powerful political lobby in the United States”  First take the leader of the national Rebuplican party;

Republican National Committee Chairman Michael Steel said on 6 March 2009:
“We are cooling. We are not warming. The warming you see out there, the supposed warming, and I am using my finger quotation marks here, is part of the cooling process.”

Ahhh.  That explains it.  Maybe the whole world is now opposite world. Warming leads to cooling.  In fact, warming is the new cooling.  Makes total sense!  (to be fair, this man says stupid things daily and even conservatives loathe and are embarrassed by him).

House Minority Leader John Boehner said on April 19 2009:
“The idea that carbon dioxide is a carcinogen that is harmful to our environment is almost comical. Every time we exhale, we exhale carbon dioxide.”

I am beginning to sense a meme here…

Republican Congressman John Shimkus said on 25 March 2009:
“If we decrease the use of carbon dioxide, are we not taking away plant food from the atmosphere”

John later elaborated:

“…the earth will end only when God declares it’s time to be over. Man will not destroy this earth. This earth will not be destroyed by a flood…. I appreciate having panelists here who are men of faith, and we can get into the theological discourse of that position, but I do believe God’s word is infallible, unchanging, perfect. Today we have about 388 parts per million in the atmosphere. I think in the age of dinosaurs, when we had the most flora and fauna, we were probably at 4,000 parts per million. There is a theological debate that this is a carbon-starved planet — not too much carbon. And the cost of a cap-and-trade on the poor is now being discovered.”

That is a pretty good one.  It may even top the God-and-climate-related rant by rep. Joe Barton, whom I blogged about last month:

Wind is God’s way of balancing heat. Wind is the way you shift heat from areas where it’s hotter to areas where it’s cooler. That’s what wind is. Wouldn’t it be ironic if in the interest of global warming we mandated massive switches to energy, which is a finite resource, which slows the winds down, which causes the temperature to go up? Now, I’m not saying that’s going to happen, Mr. Chairman, but that is definitely something on the massive scale. I mean, it does make some sense. You stop something, you can’t transfer that heat, and the heat goes up. It’s just something to think about.” – Joe Barton, from a March 10 House Energy and Commerce Committee hearing

I don’t know.  It may seem like a draw.  But I haven’t even trotted out our big gun; conservative republican senator James Inhofe.

“much of the debate over global warming is predicated on fear, rather than science.” I called the threat of catastrophic global warming the “greatest hoax ever perpetrated on the American people,”



And read here for more false statements made by US Politicians regarding climate change and the environment.

Australian PM Kevin Rudd; climate change hero


Australian PM Kevin Rudd gave a speech on climate change at the Lowy Institute for International Policy on ‘Australia, the region and the world: the challenges ahead’ last Friday.  I ran across the text of the speech today and was beyond impressed. This man, a mere politician, truly seems motivated by this issue. He really seems to get what is at stake, what needs to be done and what the political forces opposing action on climate change are.  And he quotes from Kenny Rogers!  That would win millions of red state voters here in the wild west.  (You gave us Men at Work, we give you Kenny Rogers in return).

The full speech can be read here and you can download a PDF of the transcript or listen to the speech here. And ill excerpt some highlights below.

…we are just 31 days away from the Copenhagen Conference of Parties – an historic moment to forge a global deal to put a global price on carbon.

Today we are approaching the crossroads. Both these policies are reaching crunch time.

When you strip away all the political rhetoric, all the political excuses, there are two stark choices – action or inaction. The resolve of the Australian Government is clear – we choose action, and we do so because Australia’s fundamental economic and environmental interests lie in action.

Action now. Not action delayed.

As one of the hottest and driest continents on earth, Australia’s environment and economy will be among the hardest and fastest hit by climate change if we do not act now. The scientific evidence from the CSIRO and other expert bodies have outlined the implications for Australia, in the absence of national and global action on climate change:

  • Temperatures in Australia rising by around five degrees by the end of the century.
  • By 2070, up to 40 per cent more drought months are projected in eastern Australia and up to 80 per cent more in south-western Australia.
  • A fall in irrigated agricultural production in the Murray Darling Basin of over 90 per cent by 2100.
  • Our Gross National Product dropping by nearly two and a half per cent through the course of this century from the devastation climate change would wreak on our infrastructure alone.

In Australia, we must pass our Carbon Pollution Reduction Scheme – to deliver certainty for business at home and to play our part abroad in any global agreement to bring greenhouse gases down.

President Obama in the United States is also working hard so that he can take strong commitments to Copenhagen. And let us never forget that in the US, as in Australia, under both our respective previous governments, zero action was taken on bringing in cap and trade schemes meaning that the governments that replaced them began with a zero start. Other countries are striving to build domestic political momentum in their own countries to take strong commitments into the global deal.

The opponents of action on climate change fall into one of three categories.

  • First, the climate science deniers.
  • Second, those that pay lip service to the science and the need to act on climate change but oppose every practicable mechanism being proposed to bring about that action.
  • Third, those in each country that believe their country should wait for others to act first.

It is time to be totally blunt about the agenda of the climate change skeptics in all their colours – some more sophisticated than others.

It is to destroy the CPRS at home, and it is to destroy agreed global action on climate change abroad, and our children’s fate – and our grandchildren’s fate – will lie entirely with them.

It’s time to remove any polite veneer from this debate. The stakes are that high.

Seven times the Liberals and Nationals have promised to make a decision on their policy on climate change – and seven times they have delayed.

  1. In December 2007 they said wait for Garnaut.
  2. In September 2008 they said wait for Treasury modelling.
  3. In September 2008 they said wait for the White Paper.
  4. In December 2008 they said wait until the Pearce Report.
  5. In April 2009 they said wait for the Senate Inquiry.
  6. In May 2009 they said wait for the Productivity Commission – forgetting that the Productivity Commission already made a submission on emissions trading to the Howard Government’s Shergold Report.
  7. Now the Liberals and National have said wait for Copenhagen and for President Obama’s scheme.

It is an endless cycle of delay – and I am sure that with December almost upon us, the eighth excuse cannot be far away – which will be to wait until the next year or the year after until all the rest of the world has acted at which time Australia will act.

What absolute political cowardice.

What an absolute failure of leadership.

What an absolute failure of logic.

The inescapable logic of this approach is that if every nation makes the decision not to act until others have done so, then no nation will ever act.

The immediate and inevitable consequence of this logic – if echoed in other countries – is that there will be no global deal as each nation says to its domestic constituencies that they cannot act because others have not acted.

The result is a negotiating stalemate. A permanent standoff.

And this of course is the consistent ambition of all three groups of do-nothing climate change deniers.

Coral reef scientist slams Australian government over ‘reckless vandalism’


For anyone is the Brisbane area – Dr Charlie Veron will be speaking at City Hall as part of Run for a Safe Climate (betwen 5.30-7pm). In the leadup to Copenhagen, 35  emergency services workers are running from one end of Australia to the other. Find out more at

The Age newspaper, 9th November 2009

One of the world’s leading coral reef scientists has slammed the Brumby Government’s proposal to export Victoria’s brown coal to India as “reckless vandalism”.

John “Charlie” Veron, who discovered a quarter of the world’s identified coral species, said any move to export the state’s vast reserves of brown coal would only further endanger the Great Barrier Reef.

“It’s reckless vandalism. Brown coal would have to be the dirtiest, nastiest form of energy there is. It is absolutely essential that it remains in the ground. That is obvious,” he told The Age.

The Sunday Age revealed in September that Energy Minister Peter Batchelor had championed in a Cabinet committee a 40-year proposal to export 12 million tonnes of brown coal to India. Mr Brumby has said that, given environmental approval processes, there is no reason why Victoria should not export its coal. “Australia exports oil, Australia exports gas, Australia exports black coal and Australia exports uranium,” he said. “So why you would single out brown coal and say you can’t export that?”

But Dr Veron, the Townsville-based author of the three-volume Corals of the World, said that avoiding every tonne of carbon dioxide was now crucial to save the world’s reefs. Moreover, he said science had now shown that corals will struggle to survive with the carbon dioxide levels already in the atmosphere.

High levels of carbon dioxide – the world is currently at 378 parts per million of carbon dioxide – have two impacts on corals. As the globe warms, so too does the sea, which sparks coral bleaching. But scientists now understand that the bigger problem is ocean acidification, when the chemistry of the ocean changes because of the large amounts of carbon dioxide they absorb from the atmosphere. These changes reduce the ability of reefs to form and regrow after bleaching events.

Mr Veron, who recently gave a talk on climate change and corals at the Royal Society introduced by Sir David Attenborough, said the current targets the world’s politicians are talking about – 450 and 500 parts per million – would leave only “a very small band of ocean left in which corals can live”.

“They will struggle just to exist, let alone build reefs,” said Dr Veron, who has clocked 7000 hours of diving research on coral reefs.

Brown coal, which drives 90 per cent of the state’s power supply, has been unsuitable for export because it is unstable and flammable. But proponents say recent developments in technology will allow them to dry the coal, making it less polluting – equal to black coal – and safe to transport.

The company behind the plan to export brown coal to India, Exergen, is hopeful the Government will give it access to a new release of brown coal. The company expects to earn $700 million a year in export income for Victoria.

Scientists call for urgent ‘global cooling’ to save coral reefs

Screen shot 2009-11-09 at 10.14.28 AM

UQ News, 8th November 2009

Australian marine scientists have issued an urgent call for massive and rapid worldwide cuts in carbon emissions, deep enough to prevent atmospheric CO2 levels rising to 450 parts per million (ppm).

In the lead up to United Nations Copenhagen Climate Change Conference Professors Charlie Veron (former Chief Scientist, Australian Institute of Marine Science) and Ove Hoegh-Guldberg of the ARC Centre of Excellence for Coral Reef Studies and The University of Queensland, have urged the world’s leaders to adopt a maximum global emission target of 325 parts per million (ppm).

This will be essential, they say, to save coral reefs worldwide from a catastrophic decline which threatens the livelihoods of an estimated 500 million people globally.

This is substantially lower than today’s atmospheric levels of 387 ppm, and far below the 450ppm limit envisaged by most governments attending Copenhagen as necessary to restrain global warming to a 2 degree rise, on average.

“This may take a long time. However, climate change is an intergenerational issue which will require intergenerational thinking,” Professor Hoegh-Guldberg said.

“If CO2 levels are allowed to continue to approach 450 ppm (due by 2030–2040 at the current rates at which emissions are climbing), reefs will be in rapid and terminal decline world-wide from mass coral bleaching, ocean acidification, and other environmental impacts associated with climate change,” Professor Charlie Veron, Professor Hoegh-Guldberg, Dr Janice Lough of COECRS and the Australian Institute of Marine Science and colleagues warn in a new scientific paper published in the Marine Pollution Bulletin.

“Damage to shallow reef communities will become extensive with consequent reduction of biodiversity followed by extinctions,” they said.

“Reefs will cease to be large-scale nursery grounds for fish and will cease to have most of their current value to humanity. There will be knock-on effects to ecosystems associated with reefs, and to other (marine) ecosystems.”

The researchers say that coral deaths due to bleaching were first observed when global atmospheric CO2 levels passed 320ppm in the 1970s. By the mid-1980s, at 340 ppm, sporadic, highly-destructive events were being recorded.

In the paper they argue for a long-term limit “below 350ppm” to be set.

Prof Veron told the British Royal Society recently that Australia’s Great Barrier Reef would be on ‘death row’ unless urgent action was taken to stem global carbon emissions.

“We are tracking the IPCC’s worst case scenario. The global CO2 situation, tracked by temperature and sea level rise, is now following the worst case scenario,” he says. “The people meeting at Copenhagen need to hear this message.”

At the same time CO2 emissions are turning the oceans more acidic, causing damage to corals and all life with a carbonate skeletons or shells and, if unchecked, potentially leading to mass extinctions of ocean life like those of the geological past.

“We are already well above the safe levels for the world’s coral reefs. The proposed 450ppm/2 degree target is dangerous for the world’s corals and for the 500 million people who depend on them,” Professor Hoegh-Guldberg said.

“We should not go there, not only for reasons of coral reefs, but for the many other impacts that are extremely likely.

“We deduce, from the history of coral bleaching, that the safe level for coral reefs is probably about 320 or 325ppm.

“From fossil air taken from ice cores we know the world has not exceeded 300ppm for at least the last 760,000 years, so we are already in dangerous territory.

“We are already way outside the limits that mother earth has been operating within for millions of years.”

“Then there is sea level rise. The latest scientific consensus that the minimum sea level rise we can expect globally is 1 m. The IPCC’s earlier estimates on this are now seen as far too conservative. A metre of rise will displace at least 30 million people and contaminate the underground water supplies of many coastal cities with salt.

“Tens of millions of people are going to be displaced. This is not just about corals. Big issues of food security and regional security are also at stake, and we all need to wake up to the fact that climate change is not simply about warm days.”

“It will cost less than 1 per cent of GDP growth (over the next 50 years) to sort this problem out. In times of war individual countries have devoted anything from 40 to 70 per cent of their GDP to the war effort, so the effort required to cease emitting carbon is far, far smaller.

“It is completely affordable, completely achievable.

“The consequences of not cutting carbon emissions sharply are extremely serious for humanity. It is time all people understood this.”

Ocean acidification and coral reproduction on the Great Barrier Reef


Taking the acid test on the Great Barrier Reef“, National Times, 9th November 2009

Unlike some sexual processes in the animal world, coral reproduction remains a rather magical and mysterious event. And Dr Selina Ward loves it. The thousands of little red bundles of eggs and sperm are, she says, “beautiful”.

But at Heron Island Research Station, as she waits patiently for her corals to spawn, there’s now something more to Dr Ward’s research than simply untangling the mysteries of how corals release their egg and sperm bundles to the ocean currents.

Dr Ward, from the University of Queensland’s Centre for Marine Studies, is looking at how changes in the ocean’s chemistry – driven by increasing greenhouse gases – will affect the reproduction of corals and their ability to “settle” and build new reefs.  And her preliminary results are not looking good.

When coral scientists first looked at the impact of global warming on reefs, they focused on rising sea temperatures and bleaching. This is still a concern and likely to impact large parts of the Great Barrier Reef, but the scientists now believe ocean acidification could be the process that will push the world’s reefs to the edge.

The oceans act as a big sponge for carbon dioxide produced by human industry. Since the industrial revolution, the oceans have soaked up about half of the greenhouse gases produced by humans. That carbon dioxide has reacted with the water, making the ocean more acidic. As the oceans’ pH levels drop, life becomes harder for organisms that rely on making calcium carbonate – such as corals and shell fish, and even tiny but important creatures such as krill.

Coral scientists are scrambling to understand what this process will mean for reef systems. Dr Ward’s colleagues, including well-known reef scientist Ove Hoegh-Guldberg, wrote a paper in 2007 showing that, as carbon dioxide levels increase, the worldwide area reefs can grow will shrink dramatically. Even at carbon dioxide levels of 450 and 500 parts per million (the atmosphere is now at 378 ppm) the area is very small, and does not include the Great Barrier Reef.

Last year, at the International Coral Reef Symposium, Dr Ward said about half a dozen papers were presented on the impact that ocean acidification has already had.  “They found that in the last 20 to 30 years, growth rates have suddenly dropped about 20 per cent. That could be a number of things – it could be water quality issues or that we have reached the temperature peak and it’s too hot. Or it could be that ocean acidification is kicking in.”  Scientists are also discovering that more acidic oceans leave corals even more vulnerable to bleaching.

Dr Ward’s research, which is not yet published, is one corner of this big picture. Her work involves exposing spawning coral to water at different pH levels. She is finding that the early life stages of corals are adversely affected by ocean acidification, with reductions in fertilisation and settlement (difficulty laying down the first skeleton). “If a coral can’t lay down a skeleton, they can’t build a reef, and that is a fundamental problem,” she says.