Ocean acidification climate change fears overblown, studies show
By Ian Wishart
31 March 2012
The UN IPCC has tried to drum up panic by suggesting rising CO2 absorption in the oceans is affecting the pH balance, making the seas more “acidic” and killing coral and other marine life. But the latest scientific studies are actually suggesting other factors may be at play.
“An international team of scientists has solved a mystery that has puzzled marine chemists for decades,” explained the University of Miami in 2009.“They have discovered that fish contribute a significant fraction of the oceans’ calcium carbonate production, which affects the delicate pH balance of seawater. The study gives a conservative estimate of three to 15 percent of marine calcium carbonate being produced by fish, but the researchers believe it could be up to three times higher.”
Now this is an exceptionally important study. Rising CO2 levels in the oceans cause chemical reactions that can start to harm shellfish and other marine life by dissolving their shells and exoskeletal structures. In theory. However, it appears fish can and do use the surplus CO2 in the oceans, along with calcium-rich surface waters, to create calcium carbonates, which help keep the oceans alkaline.
If you’ve owned a fish tank you’ll know fish quickly create their ideal pH level, and the same thing applies on a much bigger scale in the oceans.
“Until now,” continues the University of Miami study, “scientists believed that the oceans’ calcium carbonate, which dissolves in deep waters making seawater more alkaline, came from marine plankton.
The recent findings published in Science explain how up to 15 percent of these carbonates are, in fact, excreted by fish that continuously drink calcium-rich seawater. The ocean becomes more alkaline at much shallower depths than prior knowledge of carbonate chemistry would suggest which has puzzled oceanographers for decades.
The new findings of fish-produced calcium carbonate provides an explanation: fish produce more soluble forms of calcium carbonate, which probably dissolve more rapidly, before they [are able to] sink into the deep ocean.”
This is important, because the UN IPCC study teams have claimed the calcium carbonates produced by plankton (which sink to the ocean floor) take millions of years to re-balance the oceans, but this new study shows fish produce a much more rapidly acting form of the alkaline that can benefit the upper layers of the oceans immediately.
“The digestive systems of fish play a vital role in maintaining the health of the oceans and moderating climate change,” reported Reuters news agency on the peer-reviewed study.
“Bony fish produced a large portion of the inorganic carbon that helps maintain the oceans’ acidity balance and was vital for marine life, they said.
“The world’s bony fish population, estimated at between 812 million and 2 billion tons, helped to limit the consequences of climate change through its effect on the carbon cycle.
“ ‘This study is really the first glimpse of the huge impact fish have on our carbon cycle – and why we need them in the ocean’, researcher Villy Christensen and colleagues wrote.
“Calcium carbonate is a white, chalky material that helps control the acidity balance of sea water and is essential to the health of marine ecosystems and coral reefs.”
The probable reason for decreasing alkalinity, then, is overfishing, not CO2 emissions.(footnote 442) If we strip-mine the seas of alkaline-producing fish, we should hardly act surprised when we find less alkalinity in the seawater after a few decades of bad fishing practice. (footnote 443)
Then there’s this recent bombshell published in the journal Geology: that increasing levels of CO2 in the ocean are actually helping some shellfish thrive: (footnote 444)
In a striking finding that raises new questions about carbon dioxide’s (CO2) impact on marine life, Woods Hole Oceanographic Institution (WHOI) scientists report that some shell-building creatures – such as crabs, shrimp and lobsters – unexpectedly build more shell when exposed to ocean acidification caused by elevated levels of atmospheric carbon dioxide (CO2).
Because excess CO2 dissolves in the ocean – causing it to “acidify” – researchers have been concerned about the ability of certain organisms to maintain the strength of their shells. Carbon dioxide is known to trigger a process that reduces the abundance of carbonate ions in seawater – one of the primary materials that marine organisms use to build their calcium carbonate shells and skeletons.
The concern is that this process will trigger a weakening and decline in the shells of some species and, in the long term, upset the balance of the ocean ecosystem.
But in a study published in the Dec. 1 issue of Geology, a team led by former WHOI postdoctoral researcher Justin B. Ries found that seven of the 18 shelled species they observed actually built more shell when exposed to varying levels of increased acidification. This may be because the total amount of dissolved inorganic carbon available to them is actually increased when the ocean becomes more acidic, even though the concentration of carbonate ions is decreased.
“Most likely the organisms that responded positively were somehow able to manipulate…dissolved inorganic carbon in the fluid from which they precipitated their skeleton in a way that was beneficial to them,” said Ries, now an assistant professor in marine sciences at the University of North Carolina.
“They were somehow able to manipulate CO2…to build their skeletons.”
In truth, it’s a simple reminder of something the climate changers either forget or deliberately ignore when crafting their dumbed-down scary soundbites: when one species can no longer take the heat in the kitchen, another one rises up from the shadows swiftly to take its place that’s more resilient and even thrives in the new conditions.
The moral of the story? Life appears far more adaptable than you hear about on the TV news. The next time you hear a Greenpeace lobbyist, or a TV reporter for that matter, sensationally warning of the dangers of ocean acidification, you can be forgiven if you choose to roll all over the floor in fits of laughter.
“Fishdunnit! Mystery solved”, University of Miami news release, based on a study published in Science, 16 January 2009
www.bbsrc.ac.uk/news/archive/2009/090116-pr-marine-carbon-cycle.aspx