Archive for June, 2011

FrameWorks helps ocean scientists communicate on climate change

We depend upon our oceans for life on this planet. Our oceans not only provide food that we eat, but they also regulate the air that we breathe. However, climate change is disrupting the ocean’s ecosystem and its abilities to provide these services.

How can scientists communicate effectively to the public about the effects of climate change in the ocean?

The FrameWorks Institute was at the Woods Hole Ocean Institute in Massachusetts recently to guide science practitioners in this important endeavor.

On the first day of our engagement, we heard a presentation from Dr. Anne Cohen about the latest research on ocean acidification. She explained how carbon dioxide released from the burning of petroleum and coal for energy and transportation is absorbed by the oceans, which acts as a carbon sink. This carbon dioxide combines with water to form carbonic acid. The increase of carbonic acid in the ocean makes it difficult for marine organisms and animals to thrive. This is leading to an ecosystem collapse for marine animals such as plankton, coral, and shellfish – all of whom play an important role in the marine foodchain.
Continue reading ‘FrameWorks helps ocean scientists communicate on climate change’

Ocean extinction trend (audio)

Increased atmospheric carbon is causing a “Deadly Trio” in the world’s oceans. Alex Rogers is Scientific Director of the International Program on the State of the Ocean. He told host Bruce Gellerman that the trifecta of global warming, ocean acidification, and deoxygenation have been associated with all of the five major extinction events in paleontological history.
Continue reading ‘Ocean extinction trend (audio)’

Ocean acidification – the next big environmental problem?

Amidst the smoke and noise of the debate over green house gases and their role in global climate change, there is another, less-known but just as insidious, effect of increased atmospheric carbon dioxide (CO2). As the amount of carbon dioxide in the atmosphere increases, the pH of the ocean is dropping – a phenomenon called “ocean acidification.”

The term “ocean acidification” is somewhat misleading. On the pH scale, seven is neutral, anything below seven is acidic, and anything above is basic. Which means ocean water is slightly basic since historically, the pH of ocean water has fluctuated between 8.1 and 8.3.
Continue reading ‘Ocean acidification – the next big environmental problem?’

No reason for complacency

Papua New Guinea has some of the most pristine and diverse coral reefs on Earth. By investigating volcanic vents, where concentrations of carbon dioxide are naturally high, Fabricius et al. (Nature Clim. Change 1, 165–169; 2011) showed that these reefs are profoundly degraded by the levels of ocean acidification predicted for the end of this century. Worryingly, however, their study may underestimate the impacts of future ocean acidification.
Continue reading ‘No reason for complacency’

Ocean acidification off the south coast of Japan: A result from time series observations of CO2 parameters from 1994 to 2008

Ocean acidification resulting from increases in present and future atmospheric CO2 levels could seriously affect diverse coastal and oceanic ecosystems. In this work, we determine that a significant trend in ocean acidification is superposed on the large seasonal and interannual variabilities of acidity in surface waters off the south coast of Honshu, Japan, based on our repeated observations of partial pressure of CO2 (pCO2), total inorganic carbon (TCO2), and pH. Multiple regression analysis of TCO2 as a function of temperature, salinity, and timing of observations shows that TCO2 increased at a rate of +1.23 ± 0.40 μmol kg−1 yr−1 for the period 1994–2008, while no long-term change has been determined for total alkalinity calculated from TCO2 and pCO2 in seawater. These results indicate that pH and the aragonite saturation state (Ωarag) are decreasing at a rate of −0.020 ± 0.007 decade−1 and −0.12 ± 0.05 decade−1, respectively. If future atmospheric CO2 levels keep increasing as predicted by the Intergovernmental Panel on Climate Change emission scenario A1FI, which postulates intensive fossil fuel use associated with very rapid economic growth, a further reduction of −0.8 to −1.0 in Ωarag is likely in the next 50 years. Such a rapid reduction of Ωarag could have negative impacts on a variety of calcareous organisms.
Continue reading ‘Ocean acidification off the south coast of Japan: A result from time series observations of CO2 parameters from 1994 to 2008′

A steward for our oceans

If we are to save the seas, we must first reform 17th century ideas of marine exploitation

When you stand on a beach looking out across an ocean, the effect can be to make you feel puny. It is easy to believe that there is little we humans can do to harm, or for that matter protect, the colossal oceans. Our perception of human impotence, of our inability to affect the oceans, is deeply rooted in the way we govern the seas today.

In the 17th century Hugo Grotius developed the doctrine of the “freedom of the seas”, in the face of Portuguese and Spanish claims to sovereignty over vast areas of ocean. He argued that nobody could own the seas, which had been “created by nature for common use”; and was convinced that there were enough fish to go around, that the ocean could deal with what we threw at it and that the bounty was vast enough to share without ownership. The trouble is that then there were perhaps half a billion people – but now there are more than 6 billion of us exploiting what we now know are limited resources.

Continue reading ‘A steward for our oceans’

Seafish welcomes IPSO recommendations

Seafish has welcomed recommendations from the International Programme on the State of the Ocean (IPSO) to mitigate threats facing the marine environment.

Head of Environment, Philip MacMullen, said there is a strong need for concerted actions to address negative human impacts:

“The highly respected IPSO team identify hypoxia, anoxia, ocean warming and acidification as key stressors of the marine environment. As an industry, we share their concerns because these are the most fundamental threats to the marine food web.

“Seafish and the UK seafood industry support the six actions identified by IPSO to better manage our marine environment. We plead for the political will to drive through good governance of our marine resources.”

The IPSO report contained strong warnings on climate change and ocean acidification.
Continue reading ‘Seafish welcomes IPSO recommendations’

Will ion channels help Coccolithophores adapt to ocean acidification?

Phytoplankton come in a wide variety of shapes, sizes, and taxa, but the single-celled coccolithophores are among the most unusual. While most plankton congregate near upwellings of nutrient-rich water from the ocean floor, coccolithophores can also thrive in nutrient-poor waters. Widely dispersed throughout the oceans, these aquatic algae play an important, if not completely understood, role in carbon deposition and marine geochemical cycling and can create massive blooms visible from the sky. Their name derives from their beautiful, tiny, calcium carbonate–based scales, called coccoliths. These scales form a coat around the cells and are often produced in excess. When cells die or when blooms naturally collapse, the scales sink to the ocean floor.

Unlike other marine organisms that create calcium carbonate structures, like coral, coccolithophores produce their scales in an intracellular compartment and then secrete them to the surface. The internal calification process requires calcium and inorganic carbon as inputs. Studies indicate the algae rely on HCO3− as a carbon source for calcification, and the process of scale-building releases a mole of H+ inside the cell for every mole of calcium carbonate that is precipitated. In this issue of PLoS Biology, Alison Taylor and colleagues describe coccolithophore ion channels that allow H+ to diffuse out of the cell, showing how the cells avoid acidification. They further suggest that H+-transporting ion channels may be much more widely distributed than previously believed.
Continue reading ‘Will ion channels help Coccolithophores adapt to ocean acidification?’

Ocean chemistry: Cushion against acidification

When sulphur and nitrogen gases from ship fuel and other local sources of combustion end up in coastal waters, they strongly diminish ocean acidification by carbon dioxide.

Keith Hunter at the University of Otago in Dunedin, New Zealand, and his colleagues used a simple chemical model to compare the effects of sulphur and nitrogen oxides and ammonia on seawater chemistry with that of CO2. Results from three case studies — in the North Sea, the Baltic Sea and the South China Sea — suggest that, after chemical re-equilibration, the net effect of the gases on ocean chemistry is negligible.

Continue reading ‘Ocean chemistry: Cushion against acidification’

We need to change course: Ocean life is at risk of unprecedented extinction

Destructive fishing practices, pollution, biodiversity loss, spreading low-oxygen “dead zones” and ocean acidification are having synergistic effects across the board.

When you stand on a beach looking out across an ocean, the effect can be to make you feel puny. It is easy to believe that there is little we humans can do to harm, or for that matter protect, the colossal oceans. Our perception of human impotence, of our inability to affect the oceans, is deeply rooted in the way we govern the seas today.

The crux of the problem is that the rate of changes in ocean systems is accelerating and outstripping what was expected just a few years ago. Destructive fishing practices, pollution, biodiversity loss, spreading low-oxygen “dead zones” and ocean acidification are having synergistic effects across the board – from coastal areas to the open ocean, from the tropics to the poles.
Continue reading ‘We need to change course: Ocean life is at risk of unprecedented extinction’


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Ocean acidification in the IPCC AR5 WG II

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