Ocean acidification, effects on calcification

Ocean acidification, a consequence of the ocean’s increased absorption of CO₂ from the atmosphere, causes shifts in multiple components of the carbonate system in seawater. One of the best-known impacts of ocean acidification on coral reefs is the reduced rate of calcification in corals and coralline algae. Calcification rates of both groups are expected to decrease significantly with further increases in atmospheric CO₂ concentrations, and dissolution of reef rock and sediments will increase. The direct effects of ocean acidification on organism survival and ecosystem functioning are not well known, but loss of reef habitat and architectural complexity are expected outcomes. Findings from multiple fields of study (paleontology, paleoecology, chemical oceanography, biochemistry, isotope geochemistry, etc.) suggest that ocean acidification will lead to decreased calcium carbonate production, a shift from reef-building toward reef destruction, and reduced biodiversity of reef ecosystems.