Here are a few resources for understanding basic principles behind ocean acidification. Wood Hole Oceanographic Institution does a good job of explaining these basics and also discussing future projections and effects on organisms dependent upon calcium carbonate for shells/skeletons. On another page, WHOI shows what the composition of the different carbon species (dissolved gas, carbonic acid, bicarbonate ion, and carbonate ion) looks like under pre-industrial and 2x pre-industrial levels. Note here the rise in the bicarbonate ion, as I mentioned in class.