Monaco Declaration by scientists urges ambitious, urgent plans to cut emissions drastically

155 scientists from 26 countries have issued a declaration on the severe threat posed by ocean acidification following the 2nd symposium on “The Ocean in a High-CO2 World” held on 6-9 October 2008 at the Oceanography Museum of Monaco.

The Monaco Declaration, issued on 30 January 2009, states:

Ocean acidification is accelerating and severe damages are imminent
Currently the average concentration of atmospheric CO2 is 385 parts per million (ppm) [and increasing] At that 560-ppm level, it is expected that coral calcification rates would decline by about one-third. Yet even before that happens, formation of many coral reefs is expected to slow to the point that reef erosion will dominate. Reefs would no longer be sustainable. By the time that atmospheric CO2 reaches 450 ppm, it is projected that large areas of the polar oceans will have become corrosive to shells of key marine calcifiers.

Unfortunately, despite these specific findings, the policy recommendations made by the Declaration are vague and do not state a quantitative level to stabilise atmospheric carbon dioxide that will avoid significant impacts to the marine ecosystem.

The Declaration merely urged policymakers to develop “ambitious, urgent plans to cut emissions drastically” as one of four types of qualitative initiatives.

The Declaration is one of several made by marine scientists in recent years on the threat of climate change and ocean acidification, such as the Consensus Declaration on Coral Reef Futures issued by 50 Australian scientists from the ARC Centre of Excellence for Coral Reef Studies in 2007.
Some previous statements by similar international symposia have been more specific and suggested quantitative stabilisation targets. The Third International Tropical Marine Ecosystem Management Symposium in Mexico in October 2006 and the International Coral Reef Initiative General Meeting held in Japan in April 2007 stated that the actions required to support reef resilience to climate change include:

Limit climate change to ensure that further increases in sea temperature are limited to 2°C above preindustrial levels and ocean carbonate ion concentrations do not fall below 200 mol. kg-1.

The Monaco Declaration adds to the calls for urgent action to address the threats of climate change and ocean acidification but the vagueness of its recommendations means it is unlikely to alter national policies in this area.

Ningaloo Reef under the microscope

r147412_519770ABC News, 5th December 2008

Scientists who recently completed the most comprehensive study of the Great Barrier Reef are now turning their attention to Western Australia’s coast, focussing on Ningaloo Reef.

An Australian Institute of Marine Science study recently found the steepest drop in coral growth on the Great Barrier Reef in at least 400 years, which the Institute attributes to rising sea temperatures and ocean acidification.

The study found that on current trends coral on the Great Barrier Reef will stop growing by 2050.

The Institute’s Dr Janice Lough says scientists are now conducting a similar study on Ningaloo Reef, using coral cores to provide information about the growth of the reef, similar to the way tree rings are used to date trees.

“Some of these should contain records between about 50 to maybe 150 to 200 years, of coral growth at Ningaloo, so we’re really interested to see whether similar slowing of growth is likely to be evident in the West,” she said.

“As with people if you listen to one person they can tell you any old story, if you get a lot of people telling you the same story, or a lot of corals telling you the same story then we will believe what they’re saying, and corals don’t have any axe to grind, they are very objective about what they’re observing in the environment.”

Declining calcification on the Great Barrier Reef – Radio Interview

Glen De’ath and Katherina Fabricius, two co-authors from the recent science paper on the decline in coral calcification on the Great Barrier Reef were interviewed by Australian ABC radio this afternoon. Listen online below, or read on after the jump for a transcript.


update: fixed the link to the correct interview.
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Ocean acidification could impact jumbo squid metabolism

A new study published in PNAS (Rosa and Seibel 2008) indicates that decreased ocean pH could affect the metabolism of large squid.  See the summary article in the NYT here.


Synergistic effects of climate-related variables suggest future physiological impairment in a top ocean predator

By the end of this century, anthropogenic carbon dioxide (CO2) emissions are expected to decrease the surface ocean pH by as much as 0.3 unit. At the same time, the ocean is expected to warm with an associated expansion of the oxygen minimum layer (OML). Thus, there is a growing demand to understand the response of the marine biota to these global changes. We show that ocean acidification will substantially depress metabolic rates (31%) and activity levels (45%) in the jumbo squid, Dosidicus gigas, a top predator in the Eastern Pacific. This effect is exacerbated by high temperature. Reduced aerobic and locomotory scope in warm, high-CO2 surface waters will presumably impair predator–prey interactions with cascading consequences for growth, reproduction, and survival. Moreover, as the OML shoals, squids will have to retreat to these shallower, less hospitable, waters at night to feed and repay any oxygen debt that accumulates during their diel vertical migration into the OML. Thus, we demonstrate that, in the absence of adaptation or horizontal migration, the synergism between ocean acidification, global warming, and expanding hypoxia will compress the habitable depth range of the species. These interactions may ultimately define the long-term fate of this commercially and ecologically important predator.


The oceans’ acid test: can our reefs be saved? – a note from Frontiers in Ecology and the Environment

The journal Frontiers in Ecology and the Environment have published an interesting guest editorial article titled “The oceans’ acid test: can our reefs be saved?” by Jacqueline Savitz and Ellycia Harrould-Kolieb:

The climate change dialogue has picked up steam in recent months, but it has largely ignored the oceans, in spite of the tremendous service they provide, by absorbing millions of tons of atmospheric CO2 to buffer climate change. Frontiers and other journals have highlighted the impacts of the resulting ocean acidification, but its consequences demand a lot more attention – not just for the sake of marine ecosystems, but for our own sake as well.

National Oceanic and Atmospheric Administration scientist Richard Feely aptly called ocean acidification global warming’s “evil twin”, likely because of the disturbing trend of decreased pH that has begun to occur throughout the world’s oceans. His analogy conjures up a vision of a superhero gone bad, threatening our oceans while society innocently sleeps, which is not so far off.

This “evil twin” has the power to cause a far-reaching extinction of corals, both the tropical and deepwater varieties, along with other calcifying marine organisms, which could lead to an epic disruption of ocean ecosystems in this century. The impacts on society would be widespread, ranging from commercial losses in fisheries and tourism, to lost potential for new, life-saving pharmaceuticals that could be derived from marine species. Over time, the storm protection services provided by reefs would disappear – possibly just when they’re needed most, as global warming increases storm intensity. Ripple effects will be felt throughout the marine ecosystems, as well as among seabirds and even many terrestrial species – not to mention the aesthetic loss of the vast array of intricate, ornate, colorful reef organisms that inspire awe and wonder, and which we bear an ethical responsibility to preserve for future generations.

The need to maintain the economic, ecological, and cultural services that reefs provide has led people to ask, “What will it take for governments to finally do something about it?” Let’s face it – we live on a political planet, where action is driven largely by dollars and votes, and decisions are made based on short-term, not long-term, benefits. So if we want governments to do something about ocean acidification, we need to make clear that our dollars and our votes depend on it.

According to scientists studying climate change, such as Ken Caldeira, Ove Hoegh-Guldberg, and Jim Hansen, we need to stabilize our atmospheric CO2 levels at about 350 parts per million to prevent the loss of coral reefs. To do this, the Intergovernmental Panel on Climate Change says that countries like the US need to reduce emissions by 25–40% below 1990 levels by 2020 – and another 55% reduction from 1990 levels will be required by 2050. So we are talking about the need to convert to a very low carbon economy relatively quickly. This will be no small feat. The carbon we have been pumping into the atmosphere for free until now will cost us, retroactively. And it cannot be free from here on out, if we hope to solve the problem. Nevertheless, there is a lot we can do now.

(Read more at the Ocean Acidification Blog)

Coral Reef news round-up

“Reef guide to benefit research” (Sydney Morning Herald, 26/11/08)

‘I mean we’re not going to have reefs for much longer but we can at least have them a bit longer.” Pat Hutchings, a 40-year veteran of coral reef research, is not optimistic for the long-term future of the Great Barrier Reef but she is determined to do everything within her power to help its survival.

Hutchings has been poking around reefs since her student days, before scuba diving existed outside the armed forces. “When I went to learn in the mid to late ’60s, we had to make our own wetsuits – you couldn’t buy them,” she says. “There were a few naval divers but it wasn’t available to students. Prior to that people swam around with a box with glass on the bottom to look through.” (Read More)

“Ending the reef madness”
(The Australian, 26/11/08)

OVE Hoegh-Guldberg is blunt about the gloomy prospects for the Great Barrier Reef.

“We have no time to lose,” said the director of the University of Queensland’s Centre for Marine Studies.

“We are three decades away from having a reef with no coral and less than half the species we have today. It is crunch time.”

Speaking on the eve of the publication of a unique book, The Great Barrier Reef, the first comprehensive field guide to the world’s largest continous reef, he stressed the imperative to act. “Part of the mission for us as scientists is to pass on the urgency and excitement about these issues.” (Read More)

“Climate change, starfish hit Fiji Reefs: Study”
(ABC News, 24/11/08)

Climate change and a starfish outbreak have shrunk coral reefs near Fiji, forcing locals to change their lifestyle.

A new study, published in Global Change Biology, has found that from 2000-2006 the size of coral reefs around Fiji’s remote Lau Islands contracted by about 50 per cent.

Dr Nick Graham from James Cook University, who took part in the study, says fishing and habitat disturbance are having a big impact.

“The area was disturbed by a crown of thorns starfish outbreak in about 2000 and then, the subsequent year, there was also a coral bleaching event associated with climate change,” Mr Graham said.

“We were pretty shocked at just how severe the impact was.” (Read More)

“Oceans acidifying faster than predicted, threatening shellfish”
(Bloomberg, 25/11/08)

Oceans are acidifying 10 times faster than predicted, threatening heightened damage to coral reefs and shellfish, University of Chicago scientists said.

Researchers took more than 24,000 pH measurements over eight years and found the rate at which the ocean is becoming more acidic correlates with the atmospheric concentration of carbon dioxide, or CO2, the university said in a statement. When CO2, which helps cause global warming, dissolves in water, it forms carbonic acid.

“The acidity increased more than 10 times faster than had been predicted by climate change models and other studies,” University of Chicago ecology and evolution professor Timothy Wooton said in the statement. “This increase will have a severe impact on marine food webs and suggests that ocean acidification may be a more urgent issue than previously thought.” (Read More)

450 ppm must become the catch-cry for serious political action on climate change

Ben McNeil and Richard Matear from the University of New South Wales have just published a very important article in the Proceedings of the National Academy of United States (Link to full text).  This paper further emphasises the critical importance of keeping carbon dioxide levels lower than 450 ppm, as Chris McGrath highlighted earlier this week.  While politicians fumble over the issue of gaining effective control of carbon dioxide, there is growing evidence that we must keep CO2 levels below 450 ppm or be prepared to suffer serious consequences to life on Earth.

This is a significant paper which highlights the importance of understanding the dynamics of carbonate equilibrium in seawater in our greenhouse world.   Rapid acidification of our oceans, as we now know, is an important impact of rising anthropogenic carbon dioxide in the atmosphere.   More importantly, this study confirms the worrying conclusion that calcification in the worlds oceans is in big trouble if atmospheric levels of carbon dioxide exceed 450 ppm.   We came to a similar conclusion for coral reefs in a recent article in Science magazine (Hoegh-Guldberg et al 2007) – finding as well that net calcification on coral reef ecosystems dwindles to zero at about 450-500 ppm.   The implications of failing ecosystems as important as those in the Southern Ocean are considerable. Rigorous observations such as these should spur our political leaders to make much more decisive steps to curb the rise of carbon dioxide in the atmosphere – anything less will be disastrous.

McNeil & Matear (2008) Southern Ocean acidification: A tipping point at 450-ppm atmospheric CO2. PNAS

Southern Ocean acidification via anthropogenic CO2 uptake is expected to be detrimental to multiple calcifying plankton species by lowering the concentration of carbonate ion (CO32-) to levels where calcium carbonate (both aragonite and calcite) shells begin to dissolve. Natural seasonal variations in carbonate ion concentrations could either hasten or dampen the future onset of this undersaturation of calcium carbonate. We present a large-scale Southern Ocean observational analysis that examines the seasonal magnitude and variability of CO32- and pH. Our analysis shows an intense wintertime minimum in CO32- south of the Antarctic Polar Front and when combined with anthropogenic CO2 uptake is likely to induce aragonite undersaturation when atmospheric CO2 levels reach ~450 ppm. Under the IPCC IS92a scenario, Southern Ocean wintertime aragonite undersaturation is projected to occur by the year 2030 and no later than 2038. Some prominent calcifying plankton, in particular the Pteropod species Limacina helicina, have important veliger larval development during winter and will have to experience detrimental carbonate conditions much earlier than previously thought, with possible deleterious flow-on impacts for the wider Southern Ocean marine ecosystem. Our results highlight the critical importance of understanding seasonal carbon dynamics within all calcifying marine ecosystems such as continental shelves and coral reefs, because natural variability may potentially hasten the onset of future ocean acidification.

Plot of the year in which the onset of wintertime undersaturation occurs under equilibrium conditions (McNeil & Matear 2008)

Avoiding confusion for stabilization targets for climate change and ocean acidification

Long Cao and Ken Caldeira from the Carnegie Institution at Stanford have a new paper in Geophysical Research Letters on atmospheric carbon dioxide (CO2) stabilization and ocean acidification, a critical topic for current marine science and public policy. Hoegh-Guldberg et al (2007) illustrated the essential chemistry at the heart of this problem as follows:

Essentially, as CO2 dissolves into the oceans it forms an acid leading to decreased coral calcification and growth through the inhibition of aragonite formation (the principal crystalline form of calcium carbonate deposited in coral skeletons). The increased acidity caused by increasing atmospheric CO2 is known as ocean acidification and it is a separate, though inter-related, phenomenon to increased temperatures caused by CO2 acting as a greenhouse gas.

Cao and Caldeira (2008) found “that even at a CO2 stabilization level as low as 450 ppm, parts of the Southern Ocean become undersaturated with respect to aragonite [and] therefore, preservation of existing marine ecosystems could require a CO2 stabilization level that is lower than what might be chosen based on climate considerations alone.”

These results are similar to Hoegh-Gulberg et al (2007), who concluded “… contemplating policies that result in [CO2]atm above 500 ppm appears extremely risky for coral reefs and the tens of millions of people who depend on them directly, even under the most optimistic circumstances.”

Hoegh-Guldberg et al (2007) illustrated the expected the conditions of coral reefs under different levels of atmospheric carbon dioxide and temperature increases as follows:

These findings are very significant for governments around the world and other policy-makers because much of the current policy debate on climate change focuses on stabilizing greenhouse gases, including carbon dioxide, between 450-550 parts per million carbon dioxide equivalents, thereby allowing a rise in mean global temperatures of around 2-3°C (e.g. Stern 2007; Garnaut 2008; Australian Treasury 2008).

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“Cut greenhouse gases to save coral reefs: scientists”


Reuters, 27th August 2008

To keep coral reefs from being eaten away by increasingly acidic oceans, humans need to limit the amount of climate-warming greenhouse gases in the atmosphere, a panel of marine scientists said on Wednesday.

"The most logical and critical action to address the impacts of ocean acidification on coral reefs is to stabilize atmospheric carbon dioxide concentration," the scientists said in a document called the Honolulu Declaration, for release at a U.S. conference on coral reefs in Hawaii.

Ocean acidification is another threat to corals caused by global warming, along with rising sea levels, higher sea surface temperatures and coral bleaching, the scientists said.

Coral reefs are a "sentinel ecosystem," a sign that the environment is changing, said one of the experts, Billy Causey of the U.S. National Marine Sanctuary Program.

"Although ocean acidification is affecting the health of our oceans, the same thing — increased carbon dioxide in the atmosphere — is going to in fact be affecting terrestrial environments also," Causey said by telephone from Hawaii.

Coral reefs offer economic and environmental benefits to millions of people, including coastal protection from waves and storms and as sources of food, pharmaceuticals, jobs and revenue, the declaration said.

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