What is ocean acidification?
Ocean acidification is when carbon dioxide (CO2) is absorbed by the ocean, lowering it's pH, carbonate ion concentration, and saturation states of biologically important calcium carbonate minerals. These chemical reactions are deemed "ocean acidification" or OA.
- Since the beginning of the Industrial Revolution, the surface pH of the water has fallen 0.1 units
- Ocean acidity has increased by 30% since the beginning of the Industrial Revolution. This increase is 100 times faster than any change in acidity experienced by marine organisms for at least the last 20 million years.
Over the past 300 million years, the ocean's pH has been about average to basic slightly, averaging about 8.2. Today, it is around 8.1, a drop of 0.1 pH units, which is a 25-percent increase in acidity over the past two centuries