Skip to comments.Immediate Action Needed To Save Corals From Climate Change
Posted on 12/14/2007 8:41:13 AM PST by cogitator
The journal Science has published a paper that is the most comprehensive review to date of the effects rising ocean temperatures are having on the world's coral reefs. The Carbon Crisis: Coral Reefs under Rapid Climate Change and Ocean Acidification, co-authored by seventeen marine scientists from seven different countries, reveals that most coral reefs will not survive the drastic increases in global temperatures and atmospheric CO2 unless governments act immediately to combat current trends.
The paper, the cover story for this week's issue of Science, paints a bleak picture of a future without all but the most resilient coral species if atmospheric CO2 levels continue on their current trajectory. Marine biodiversity, tourism and fishing industries and the food security of millions are at risk, the paper warns. Coral reef fisheries in Asia currently provide protein for one billion people and the total net economic value of services provided by corals is estimated to be $30 billion.
Dr. Bob Steneck, of the University of Maine and co-author of the paper, said the time was right for international leaders to commit to meaningful action to save the world's coral reefs: "The science speaks for itself. We have created conditions on Earth unlike anything most species alive today have experienced in their evolutionary history. Corals are feeling the effects of our actions and it is now or never if we want to safeguard these marine creatures and the livelihoods that depend on them."
Scientists have long thought that the effects of climate change and the resulting acidification of the oceans spells trouble for reefs. Coral skeletons are made of calcium, and reef development requires plenty of carbonate ions to build these skeletons, a process called calcification. When carbon dioxide is absorbed in the ocean, the pH level drops, along with the amount of carbonate ions, slowing the growth of coral reefs.
Atmospheric CO2 levels are currently at 380 parts per million (ppm) and the paper's authors, members of the Coral Reef Targeted Research and Capacity Building for Management Program (CRTR), calculate that once levels reach 560ppm, the calcification process could be reduced by up to 40 percent. Recent science also suggests that by 2100 the oceans will be so acidic that 70 percent of the habitat for deep-water corals, once considered relatively safe from the effects of climate change, will be uninhabitable.
Ocean acidification is just one example of the threats corals are facing. Bleaching, a process that is triggered when summer sea temperatures rise above normal for weeks at a time, causes corals to expel the algae that gives them their colour and nutrients. This phenomenon killed 16 percent of reef-building corals in 1997, according to the paper's authors. Destructive fishing methods, oil and gas exploration and pollution have also contributed to the global decline of coral reefs, with 20 percent already destroyed and another 50 percent threatened or verging on collapse in just the past few decades.
Consumer demand has also placed corals at risk. Popular products include coral jewelry, home decor items and live animals used in home aquaria. Corals grow so slowly it can take decades for them to recover, if at all. Catches of precious red corals, the most valuable of all coral species, provide a striking example of how demand for a fashion item can decimate a species. Red coral populations have plummeted 89 percent in the past two decades. Conscientious companies such as Tiffany and Co. removed real coral from their product lines over five years ago.
Fernanda Kellogg, president of The Tiffany and Co. Foundation, said, "Tiffany and Co. is committed to obtaining precious materials in ways that are socially and environmentally responsible. We decided to stop using real coral in our jewelry and feel that there are much better alternatives that celebrate the beauty of the ocean without destroying it."
Yet there is hope for corals and the life that depends on them. Scientists are calling for a reduction of carbon emissions to ensure corals' survival. It is also vitally important to reduce local pressures on corals such as overfishing, removal for consumer items, and pollution. If these local pressures are addresssed, coral populations will be stronger and will have a better chance of surviving climate change. Tiffany and Co. is forming new partnerships with fashion designers, scientists and conservation organizations to raise awareness of the urgent need for coral conservation.
Dawn M. Martin, president of SeaWeb, said, "Corals belong in the ocean, not in our homes or in our jewelry boxes. Consumers and the fashion industry can play an important role in the ocean's recovery by simply avoiding purchases of red and other corals. These jewels of the sea are simply too precious to wear."
In 2008, scientists, conservationists and governments will mobilize around the world to celebrate the International Year of the Reef (IYOR), a worldwide initiative to raise awareness of the importance of corals and coral reefs. The 11th International Coral Reef Symposium will be held July 7-11, 2008, in Fort Lauderdale, Florida. Over 2,500 attendees from academic, government and conservation organizations are expected to attend to discuss the latest coral science and its implications for the survival of these international treasures.
Try this on for size:
"James Zachos, professor of Earth sciences at the University of California, Santa Cruz, led an international team of scientists that analyzed marine sediments deposited during a period of extreme global warming known as the Paleocene-Eocene Thermal Maximum (PETM), in which temperatures rose by as much as 10 degrees in a relatively short period of time. Sediment cores drilled from the ocean floor revealed an abrupt change in ocean chemistry at the start of the PETM 55 million years ago, followed by a recovery that took at least 80,000 years."
"This absorption of carbon dioxide by the world's oceans will have a significant impact on marine organisms if past events are any indication of the future. When carbon dioxide dissolves in water it makes the water more acidic by stripping out carbonate ions, which are essential for marine organisms to build calcium carbonate shells and exoskeletons. During the PETM, ocean acidification likely caused a mass extinction of phytoplankton -- microorganisms key to the prehistoric food chain."
What the article doesn't state -- but which you can confirm by reading the link below -- is that the PETM was caused by a massive and rapid increase in atmospheric methane, which oxidized to CO2. Enjoy.
Totally outside of anything that can happen on the Earth,
Not really; depends on how much dry ice you add. I did the experiment in aquatic chemistry as an undergrad where you create the simple seawater carbonate buffer system (leaving out some of the minor stuff, like boric ion), and then just breathe into the flask. The increase in CO2 simply from your exhalations is sufficient to alter the pH of the system. But for that you have to wait 3-4 days. Dry ice will do it faster, because it will put a lot more carbonic acid into the system.
You'll need a decent pH meter.
Adding CO2 increases acidity, not pH. And if you increase carbon (through CO2)...you get...more carbonate (that ol'mass balance thingy).
My intial point is that the oceans have always been saturated at various levels and temps that are well within the CO2 concentrations that have existed in the past. Corals have been there all during that time.
The diagram on page 2 of that pdf is overly simplistic and misleading. It ignores the rest of the local system which includes the decrease in bicarb and increase in carbonate with increased CO2 partial pressure. IOWs the local system will not have CO32- decreasing to keep a constant alkalinity. The alkalinity will go up, and the pH change will stay the same, or change much less.
The trick they pulled is doing it in glass, instead of a reef with local and global mineral deposits and dead coral, which they later discuss in the text. Also note that as the corals themselves grow, HCO3- -> CO32- + H+, which increases the local dissolution rate.
Nevertheless, the rest of the paper and the summary shows there is nothing to the claim, "the corals are facing a serious problem".
That is a very interesting experiment. This is Friday, so it is too late for my wife to bring home some dry ice from the hospital. However, on Monday, I should be able to do this experiment.
Question: How will the pH of saltwater alter in a 100% CO2 atmosphere?
My guess is that the pH will not change, but you got me rather curious. This is an experiment that I will perform.
Beam me up Scotty. I think I will go to Vulcan. At least there they are "logical". I think...
Would you like me to video this experiment, so that you can insure that I did it correctly?
I hope all the G-W douches, beginning with Al Gore, chain themselves in protest to the nearest coral reef.
Hey, that is what the dinosaurs must have done. They were so big and were breathing SO much CO2 into the air that they decided to commit mass suicide to save the planet! I mean some of those things were very big and just imagine how much CO2 each one of them spewed into the air! That has to explain it.
Don't know. If so, that means it's been high & dry at least four times during the roughly 100k year ice cycles. It's also mean the in the last half a million years the very existence of the reef is the exception, not the rule.
In the last million years our current climate in it's entirety is the exception. 100,000 years of cold, 10 - 14 thousand of warm, if I recall correctly.
This WEATHER CONTROL scheme that the green libs are selling is an attempt to control that which they do not understand for gain of money or power, and as such are nothing more than traveling rainmakers of the past scamming small towns and communities of their savings then moving on to the next sucker.
Sounds like a great new lucrative cottage industry. You know, I AM a marine biologist.
Not necessary. But don't forget to seal the flask.
You might find this interesting supporting material:
And have fun!
Of course I will seal the flask. This experiment is to test the pH change of saltwater in a 100% CO2 atmosphere.
I just read a study that gave empirical evidence showing that 1000ppm CO2 actually helped the coral grow faster and larger. I’ll get back to this thread later. Is this another unverifiable computer model?
This paper is pretty weak. They did a literature survey and made this hypothesis with no supporting research or evidence.
They are calling for more funding and research to test their hypothesis.
Mammoth site sounds cool too! I hope to make a cross country trip some day through the northern plains, Just to see how much open space there still is.
Stay Warm up there.
Coral has survived billions of years of volcanoes, asteroid impacts, super continent breakups, solar insolation variations, oceanic plate subduction, etc.
That makes no sense. CO2 dissolves in water according to it's pressure. The other gasses don't matter in the first approximation.
The equation that determines the concentration of a gas in water is:
pGAS = kGAS * NGAS / NH2O
Where N is the number of moles/volume. A mole is the weight of substance/it's molecular weight. So...
pCO2 = kCO2 * NCO2 / NH2O
Each gas dissolves according to it's pressure. If dry ice is used, the pressure is 760 mm Hg(torr), or 14.7 PSI. The normal pressure for CO2 at 380ppmv is 0.29 torr, or 0.0056 PSI. Note hte total pressure of the atmosphere, 14.7 PSI, is a sum of the pressures for each gas in the atmosphere. So 20% oxygen means the oxygen pressure, pO2 is 0.2*14.7=2.9PSI