My pet theory is that no matter how ridiculous a concept may be, you can find at least one person with a PhD in that field who will advocate it (e.g., a microscopic number of biologists who are creationists). So where are the marine biologists who don't think ocean acidification is a significant concern?
You'll find researchers who publish an occasional piece of good news about marine life adapting to acidifying oceans, but I'd like someone to show me a marine biologist who has gone on to make the general conclusion "meh, acidification isn't something to be worried about."
Maybe I've just missed it, that marine biologist is out there and can rescue my pet theory. Or maybe they just haven't seen the value in being the next Bozo Galileo. I think the climate denialists rarely get paid for their services but this person might be one of the exceptions. The psychological reward is still more likely, some level of acceptance of their heroism.
UPDATE: see John and John comments below for a range of opinion re whether climate denialists are "rarely" paid. I agree with John that the issue is partly definitional. Probably worth its own separate post, but I think a useful context is the anti-fluoride activists and 9-11 Truthers - there's even less money to be made in their fields, and they're still legion, even if the latter group is declining.