Quote:If the pH of the ocean decreased by 0.1 I'd say it has become less caustic, since it's still very alkaline.


As far as adversely affecting development, the pH of an ecosystem can change by 0.3 over the course of a day, so sea life is used to various levels of the pH. I might add that the whole claim that corals will be harmed if the pH is slightly lower is ridiculous. Corals have existed on Earth since before the dinosaurs, and the pH and CO2 levels have varied a whole lot more than the result of any man-made CO2 increase will ever achieve.

In regards to the rate of change:


One of the first detailed datasets to examine how pH varied over a period of time at a temperate coastal location found that acidification was occurring much faster than previously predicted, with consequences for near-shore benthic ecosystems. Thomas Lovejoy, former chief biodiversity advisor to the World Bank, has suggested that "the acidity of the oceans will more than double in the next 40 years. This rate is 100 times faster than any changes in ocean acidity in the last 20 million years, making it unlikely that marine life can somehow adapt to the changes. It is predicted that, by the year 2100, the level of acidity in the ocean will reach the levels experienced by the earth 20 million years ago.


Current rates of ocean acidification have been compared with the greenhouse event at the Paleocene–Eocene boundary (about 55 million years ago) when surface ocean temperatures rose by 5–6 degrees Celsius. No catastrophe was seen in surface ecosystems, yet bottom-dwelling organisms in the deep ocean experienced a major extinction. The current acidification is on a path to reach levels higher than any seen in the last 65 million years, and the rate of increase is about ten times the rate that preceded the Paleocene–Eocene mass extinction. The current and projected acidification has been described as an almost unprecedented geological event. A National Research Council study released in April 2010 likewise concluded that "the level of acid in the oceans is increasing at an unprecedented rate." A 2012 paper in the journal Science examined the geological record in an attempt to find a historical analog for current global conditions as well as those of the future. The researchers determined that the current rate of ocean acidification is faster than at any time in the past 300 million years.


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Wow, that sounds wonderful. Thank goodness you are here to supply your folksie, homespun pseudo science or else we might actually get worried.

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