Oceans are turning acidic as a result of increased Carbon dioxide emission. As they act as sponge for these emissions so the level of carbon dioxide is found to be increasing in them. What actually happens? Due to absorption of carbon dioxide pH is lowered, hence acidic, and you know what is the major issue? The pH scale is logarithmic, this means that impact of minor drop in pH can have profound impacts.
Thus oceanic ecosystem as a whole is being disturbed as a result of ocean acidification. Calcifers (oysters, shell-fish etc) suffer most, because carbonate and acidity are inversely related, and these animals require carbonate for building and strengthening their shells. Corals have been reported to show decline in growth in presence of acidic media.
Similarly lowering of pH effects health of several fishes, as they are incapable of breathing. However, some plants and predators are positively effected. Loss of habitat for some oceanic creatures, such as turtles, is another unfavorable consequence.
Oceans play a vital role in sustaining biosphere. Thus, to cope with this predicament measures such as inhibition of oil exploration in water bodies and shifting to green technology (renewable) are the only best solutions we are left with.
(Picture credits: Clams on the “No” Shell)