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  • Ocean acidification

Ocean acidification

Scientists are becoming increasingly worried about ocean acidification, a direct result of the increase in atmospheric CO2 levels. On 30 June 2005, the Royal Society of London published a Report on why this is important:

  • carbon dioxide from the atmosphere dissolves in the ocean, and makes it acid.
  • This is inevitable with high carbon dioxide, no fancy models are involved.
  • The oceans are already 30% more acid that before fossil fuel burning started
  • Acidification will kill corals, and probably make many other species (like squid) extinct
  • The overall effects are unknown - there has been no period like this in the last 2 Million years

The UK Royal Society has commented that �the effects of ocean acidifcation have potentially catastrophic consequences for marine life� .

There is an equilibrium between atmospheric CO2 and the CO2 dissolved in seawater: as atmospheric levels increase, so do the levels of CO2 dissolved in the ocean waters, especially in the surface waters where most ocean life flourishes. The dissolved CO2 reacts with the seawater to form carbonic acid (H2CO3), increasing the water acidify (i.e. reducing pH). The exact results of this are unknown, but are potentially disasterous as common marine organisms, such as the fishes we use as food, may be unable to survive.

It is important to note that the issue of seawater acidification is not related to global warming - there is no dispute about the reality of ocean acidification, only about the consequences.

Researchers at Lawrence Livermore National Laboratory published a paper in the science journal Nature, suggesting that continued  increases in atmospheric CO2 could alter ocean pH values - an effect greater than any experienced in the past 300 million years (Caldeira, K. & Wickett, M.E., 2003, Nature, v. 425. p. 365).

As a consequence, research programmes have been started by several organizations: the International Global Biosphere Programme (IGBP); the Scientific Committee on Oceanic Research (SCOR); the Commission On Atmospheric Chemistry and Global Pollution (CACGP); and the International Council for Science (ICS).

One outcome was a Symposium on The Oceans in a High-CO2 World in May 2004, sponsored by SCOR and the Intergovernmental Oceanographic Commission (IOC�part of UNESCO). The resulting report � Priorities for Research on the Ocean in a High-CO2 World � concludes that more research in this area is urgently needed.

A member of the Royal Society working group, Dr Carol Turley of the Plymouth Marine Laboratory, presented a paper on the impact of increasing ocean acidification on marine ecosystems at the scientific conference Avoiding Dangerous Climate Change held on 1-3 February 2005 at the Met Office in Exeter, UK. This can be downloaded in pdf format by clicking here.

Dr Turley said ocean acidification represented �potentially a gigantic problem for the world.� She added: �It�s urgent indeed to warn people what�s happening. Many of the marine species we rely on to eat could well disappear. In cartoon terms, you could say people should prepare to change their tastes, and switch from cod and chips, to jellyfish and chips.� (The Independent)

Ocean acidifcation could change the ocean ecosystems, driving our marine food species to extinction. It is essential to reduce atmospheric CO2, even if you do not believe in climate change !

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Last modified: 16 Apr, 2009
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