Ocean Acidification: Another Failing Scare Story?

Source: Courtesy of Master Resource

by Chip Knappenberger
January 6, 2010

As projections of catastrophic climate changes are being beaten down by the far less than catastrophic actual climate response, other calamities that may result from our untoward use of fossil fuels are being offered up for our consideration. Besides the well-worn pitfalls of our failure to achieve energy independence, or to be the first to grasp green technologies, a new problem is being worked into the mix?ocean acidification.

Ocean acidification. Sounds bad doesn?t it. Much worse than say, ?the oceans are becoming less basic? which is a more accurate, but less worrisome-sounding description. In either case, it is used to describe the situation in which the oceans absorb an increasing amount of carbon dioxide as the atmospheric partial pressure of CO2 increases. The dissolution of CO2 in the oceans has the net effect of increasing the hydrogen ion concentration which drives the ocean?s pH lower. The pH of the global oceans averages about 8.1 so it is considered a base rather than an acid (acids have pH values less than 7.0) and has perhaps dropped by 0.1pH units (a logarithmic scale) since the Industrial Revolution.

The reason we are being told that this is bad, is that it potentially disrupts some ocean ecosystems, primarily coral reefs and other calcifying organisms. The idea is that a lower pH interferes with the production of shells and/or causes the shells of some organisms to dissolve?leading to thinner, weaker defenses and other detrimental effects increasing the vulnerability of these organisms and jeopardizing the livelihood of other organisms that depend on them leading to a downward spiral of ever-increasing breadth.

Eager to bring this to the attention of the general public and shore up the public?s waning concerns about global warming (and rally them behind anti-greenhouse gas legislation), the National Resources Defense Council (NRDC) produced a 21-minute movie titled ?Acid Test: The Global Challenge of Ocean Acidification? narrated by Sigourney Weaver. Here is taste of what is inside:

Carbon dioxide pollution is transforming the chemistry of the oceans, rapidly making the water more acidic. In decades, rising ocean acidity may challenge life on a scale that has not occurred for tens of millions of years. So we confront an urgent choice, to move beyond fossil fuels or to risk turning the ocean into a sea of weeds.

Scary scenario. But as with most good horror movies, the real world proves to be a much more benign locale.

The folks over at the Science and Public Policy Institute have taken it upon themselves to look a bit more closely into the ocean acidification story and see just what the scientific literature has to say about how organisms are actually responding to changes in ocean pH rather than just talk about how they may respond.

What SPPI finds is neither newsworthy nor catastrophic, simply that, as has always been the case, the aquatic organisms of the world?s oceans are very adaptable and are able to respond to environmental changes in such a way as to avoid large-scale detrimental impacts.

The SPPI conclusions are derived from the body of peer-reviewed articles published in the scientific literature. SPPI has described and summarized the literature on the subject of ocean acidification in a series of thoroughly referenced publications, including two books published within the past year, CO2, Global Warming, and Coral Reefs , and CO2, Global Warming, and Species Extinctions: Prospects for the Future , both written and compiled largely by Dr. Craig Idso after a tedious amount of time spent surveying the peer-reviewed literature.

Additionally, SPPI has just announced its release of a strong critique of the NRDC documentary (also based upon Dr. Idso?s efforts). Here is the summary:

So what?s the story here? Are coral reefs really in their last decades of existence? Will the shells of other calcifying marine life also dissolve away during our lifetimes? The NRDC film certainly makes it appear that such is the case; but a little scientific sleuthing reveals nothing of substance in this regard. In fact, even a cursory review of the peer-reviewed scientific literature reveals that an equally strong case ? if not a more persuasive one ? can be made for the proposition that the ongoing rise in atmospheric CO2 concentration will actually prove a boon to calcifying marine life. Sadly, however, the NRDC chose to present an extreme one-sided, propagandized view of ocean acidification; and in this critique we present the part of the story that they clearly don?t want you to know.

From there the SPPI report goes on the describe the results of well over 100 articles that together do not paint an overly dire picture of the future of the world?s oceans as a result of the increasing atmospheric CO2 burden. Neither corals nor other calcifying organisms seem to display an overall negative response, and in fact, there is some evidence that some responses may in fact be positive as atmospheric CO2 levels increase.

The SPPI report concludes:

In conclusion, based on the many real-world observations and laboratory experiments described above, it is clear that recent theoretical claims of impending marine species extinctions, due to increases in the atmosphere?s CO2 concentration, have no basis in empirical reality. In fact, these unsupportable contentions are typically refuted by demonstrable facts.

And further,

Finally, if there is a lesson to be learned from the materials presented in this document, it is that far too many predictions of CO2-induced catastrophes are looked upon as sure-to-occur, when real-world observations show such doomsday scenarios to be highly unlikely or even virtual impossibilities. The phenomenon of CO2-induced ocean acidification is no different. Rising atmospheric CO2 concentrations are not the bane of the biosphere; they are an invaluable boon to the planet?s many life forms.

Overall the SPPI report makes for a fascinating (although quite technical) read. I recommend it to anyone who wants to get into the nitty-gitty details of how marine organisms from corals, to phytoplankton, to fish respond to changes in the ocean?s chemistry as a result from atmospheric CO2 enrichment. By the end, after turning page after page full of examples from the scientific literature that seem to run counter to the ocean-acidification-is-most-certainly-going to-be-bad mantra, you really begin to wonder whether ocean acidification is any more than much ado about nothing.