http://www.nytimes.com/2009/01/31/science/earth/31ocean.htmlJanuary 31, 2009
Rising Acidity Threatens Oceans
By CORNELIA DEAN
The oceans have long buffered the effects of climate change by absorbing a substantial portion of the greenhouse gas carbon dioxide. But this benefit has a catch: as the gas dissolves, it makes seawater more acidic. Now an international panel of marine scientists says this acidity is accelerating so fast it threatens the survival of coral reefs, shellfish and the marine food web generally.
The panel, comprising 155 scientists from 26 countries and organized by the United Nations and other international groups, is not the first to point to growing ocean acidity as an environmental threat, but its blunt language and international credentials give its assessment unusual force. It called for “urgent action” to sharply reduce emissions of carbon dioxide.
“Severe damages are imminent,” the group said Friday in a statement summing up its deliberations at a symposium in Monaco last October.
The statement, called the Monaco Declaration, said increasing acidity is interfering with the growth and health of shellfish and eating away at coral reefs, processes that would eventually affect marine food webs generally.
…Press Release:
http://www.igbp.kva.se/page.php?pid=455 Ocean acidification is accelerating and severe damages are imminent
(29 January 2009) Urgent action is needed to limit damages to marine ecosystems, including coral reefs and fisheries, due to increasing ocean acidity, according to 155 of the world’s scientific experts who will release the Monaco Declaration this Friday.
The Declaration is based on results from the Second International Symposium on the Ocean in a High-CO2 World, held at the Oceanography Museum in Monaco last October and organised by the International Geosphere-Biosphere Programme (IGBP), UNESCO’s Intergovernmental Oceanographic Commission, the Scientific Committee on Oceanic Research (
SCOR) and the International Atomic Energy Agency (
IAEA).
The ocean absorbs a quarter of the carbon dioxide emitted into the atmosphere from human activities. Observations from the last 25 years show increasing acidity in surface seawater, following trends in increasing atmospheric CO2.
“Measured recent increases in ocean acidity follow exactly what is expected from basic chemistry; meanwhile, key ocean regions reveal decreases in shell weights and corals that are less able to build skeletal material,” explains Dr. James Orr, of the Marine Environment Laboratories (MEL-IAEA), Monaco and Chairman of the symposium’s International Scientific Committee.
“The Monaco Declaration is a clear statement from this expert group of marine scientists that ocean acidification is happening fast and highlights the critical importance of documenting associated changes to marine life ”, says Professor Sybil Seitzinger, Executive Director of the International Geosphere-Biosphere Programme (IGBP), one of the sponsors of the Symposium.
According to the experts, ocean acidification may render most regions of the ocean inhospitable to coral reefs by 2050, if atmospheric CO2 levels continue to increase. It could lead to substantial changes in commercial fish stocks, threatening food security for millions of people as well as the multi-billion dollar fishing industry.
The Declaration draws attention to the “other CO2 problem”. Carbon dioxide, a greenhouse gas responsible for increases in global temperature and climate change, is also a pollutant which causes acidification of the ocean. The scientists behind the Declaration urge policymakers around the world to develop ambitious, urgent plans to cut CO2 emissions drastically to prevent severe damages from ocean acidification.
According to Dr. Hermann Held of the Potsdam Institute for Climate Impact Research, Germany, who helped craft the Declaration, “About 2 % of the Gross World Product would need to be invested in energy production, efficiency and usage to reach the stabilisation target of 450 ppm, a cost considered to be tolerable by most economists”.
“I strongly support this declaration”, says Prince Albert II of Monaco, whose environmental foundation provided support for the symposium. He added, “I hope the declaration will be heard by all the political leaders meeting in Copenhagen in December 2009”, at the United Nations Climate Change Conference, COP15.
Note to Editors: The Monaco Declaration will be released at a press conference at 11:30 on Friday 30 January at the Acropolis Convention Centre in Nice, France during the ASLO* International Aquatic Sciences Meeting. A more detailed report from the Monaco Symposium, “A report on Research Priorities for Ocean Acidification” will also be launched at this time, available from
www.ocean-acidification.net.
*Society for Advancing the Science of Limnology and Oceanography
For more information and to arrange an interview contact: Lina Hansson at the ASLO Meeting in Nice, France +33-6 2482 8718 or Wendy Broadgate at the IGBP Secretariat in Stockholm, Sweden + 46 70 966 2181,
www.igbp.net…
We scientists who met in Monaco to review what is known about ocean acidification declare that we are deeply concerned by recent, rapid changes in ocean chemistry and their potential, within decades, to severely affect marine organisms, food webs, biodiversity, and fisheries. To avoid severe and widespread damages, all of which are ultimately driven by increasing concentrations of atmospheric carbon dioxide (CO2), we call for policymakers to act quickly to incorporate these concerns into plans to stabilize atmospheric CO2 at a safe level to avoid not only dangerous climate change but also dangerous ocean acidification.
Ocean acidification is underway
The surface ocean currently absorbs about one-fourth of the CO2 emitted to the atmosphere from human activities, namely from fossil-fuel combustion, deforestation, and cement production. As this CO2 dissolves in seawater, it forms carbonic acid, increasing ocean acidity. Since industrialization began in the 18th century, surface-ocean acidity has increased by 30%. This ongoing ocean acidification is decreasing the ability of many marine organisms to build their shells and skeletal structure. Increasing acidity and related changes in seawater chemistry also affect reproduction, behaviour, and general physiological functions of some marine organisms, such as oysters, sea urchins, and squid.
Ocean acidification is already detectable
Observations collected over the last 25 years show consistent trends of increasing acidity in surface waters that follow increasing atmospheric CO2. These trends match precisely what is expected based on basic marine chemistry and continuous measurements of atmospheric CO2. A range of field studies suggest that impacts of acidification on some major marine calcifiers may already be detectable. Also, naturally high-CO2 marine environments exhibit major shifts in marine ecosystems following trends expected from laboratory experiments. Ocean acidification has altered some coastal waters to the extent that recently during spring they have become corrosive to the shells of some bottom-dwelling organisms. Within decades these shell-dissolving conditions are projected to be reached and to persist throughout most of the year in the polar oceans.
Ocean acidification is accelerating and severe damages are imminent
Currently the average concentration of atmospheric CO2 is 385 parts per million (ppm), which is 38% more than the preindustrial level of 280 ppm. Half of that increase has occurred in the last 30 years. Current CO2 emissions are greater than projected for the worst-case scenario formulated a decade ago. And along with increasing emissions, the increase in atmospheric CO2 is accelerating. By mid-century, the average atmospheric CO2 concentration could easily reach double the preindustrial concentration. 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.
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