claim: “[ … ]The impact on calcification, metabolism, growth, fertility and survival of calcifying marine species when pH is lowered up to 0.3 units [ … ] is beneficial, not damaging.
evidence: The German Advisory Council on Global Change stated : In order to prevent disruption of the calcification of marine organisms and the resultant risk of fundamentally altering marine food webs, the following guard rail should be obeyed : the pH of near surface waters should not drop more than 0.2 units below the pre-industrial average value in any larger ocean region ( nor in the global mean ).