Dear David Lum,

I applaud your skepticism. You raise an interesting question regarding volcanic activity: with all the sulphuric acid pouring into the sea in Hawaii, why are calcareous organisms still present if oceanic acidification is such an issue?

In the absence of data for Hawaii, the answer seems to be that aragonitic saturation is much higher in tropical seas than near the poles. There may be an effect but it would not be as dramatic as in colder waters. In addition, epochs of intense global volcanic activity have been tied to massive die-offs, such as during the Paleocene-Eocene Thermal Maximum 55 million years ago (with carbon dioxide increase and ocean acidification being among the prime suspects).

The model used by Orr, et al, predicts spreading areas of undersaturation in circumpolar regions during the next 90 years. An animation can be seen (together with images of other calcified marine organisms) at http://www.ipsl.jussieu.fr/~jomce/acidification/

Here's a more directly shell-related finding that I don't remember being discussed on Conch-L yet: living pteropod shells start dissolving rapidly with undersaturation conditions projected for the year 2100. There are SEM images of damage to a Clio pyramidata shell available in a Nature article that can be found online as a pdf. (Vol 437|29September2005|doi:10.1038/nature04095)

Work in your home state of Hawaii shows that decreased alkalinity hampers the growth of coralline algae (often seen as pink dots on shells and rocks). The team at Kane'ohe Bay points out that coralline algae may sometimes be more essential to reef-building than coral itself due to its binding quality.

But the original article I cited actually measured an increase in acidity -- across one large coastline. So, the changes are not as likely to be just hypothetical or isolated.

When you questioned the integrity of the scientists who've been doing this research, I thought to myself, "Now, there's a food fight ("food-chain fight"?) I'd like to see." Those publicity-seeking, money-grubbing, sensationalistic people who call themselves scientists and publish in Nature or Science will have to step into the ring against the selfless, impartial executives at ExxonMobil and the "Clean Coal" leaders (who bring us frequent TV reminders on how to mine an oxymoron). What a match-up!

The investigations into the question of acidification are just beginning. It's a complex matter with many variables and mitigating processes. There need to be hard questions.

Some people have concluded that since there's uncertainty, nothing should be done. That suits the fossil fuel interests just fine. However, it's been pointed out that the costs of doing nothing and being wrong far outweigh the costs of doing something and being wrong.

David Kirsh
Durham, NC



"It makes you feel good to know that there are other people who are afflicted like you." --Harvey Pekar

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