Ocean acidification results from the solubility of CO2 in oceans increasing the H+ concentrations, and depletion of bicarbonates concentrations.
Therefore, human activities which increases the concentration of CO2 in the atmosphere, will raise the atmospheric CO2 concentration. CO2 is constantly being absorbed by green plants maintaining its concentration through carbon cycle,Therefore massive deforestation which removes green plants, cutting down photosynthesis is one of human activities which raises CO2 levels of the atmosphere.The CO2 dissolves in the oceans to raise its acidic levels.Lower pH.
Another source is fossil fuels emissions which add more CO2 to the atmosphere.
