How bad is the problem right now?
"Corrosive water between 600 and 700 feet deep has already been detected off the continental shelf of Washington, Oregon and Alaska" said NOAA scientist Richard Feely
So what? Why should we worry? Because the entire ocean food web could unravel. Anything that uses calcium carbonate, for shells or bones will have a hard time making shells or bones. Where acidification is severe, corrosive water will dissolve shells or bones and make it impossible to grow more.
The biggest bad news is that ocean acidification won't go away quickly, even if we reduce CO2 in the atmosphere. Some scientists say the ocean will become permanently more acidic.
“For all practical purposes, this is permanent,” said Steven Emerson, UW oceanography professor. “That’s not true of temperature. But with ocean acidification, the time scales are long.”