Earth Magazine has a new claim about ocean acidification :-
Human emissions of carbon dioxide are currently acidifying the oceans at a rate unprecedented in the last 300 million years — since well before the dinosaurs evolved — according to a study published today in Science. More acidic water can dissolve the shells of many marine organisms, including reef- and shell-building species, such as clams, oysters and corals, as well tiny organisms that form the base of the food chain.
However the potential for alarm, or even serious consideration, is somewhat inhibited when we learn :-
An international team of about 20 researchers, led by geochemist Bärbel Hönisch at Columbia University’sLamont-Doherty Earth Observatory, conducted a literature review to compile a record of ocean pH levels extending back to the Permian, the longest acidification timeline put together to date.
So it's some kind of reading group telling us what they've read. They should get out more.