Due to increased use of fossil fuels since the Industrial Revolution, the amount CO2 in Earth’s atmosphere has nearly doubled.
The Ocean has served to absorb about 1/3 of this pollution, but the CO2 filtering process acidifies ocean water by by lowering its pH balance.
Currently, the Ocean absorbs about 22 million tons of CO2 per day.
Acidification of the Ocean has several potentially catastrophic consequences for marine life:
- Adding CO2 to seawater affects calcifying organisms by upsetting the natural equilibrium of calcium carbonate chemistry in the ocean. This means that animals such as shellfish, sea snails and corals are not able to absorb enough calcium carbonate to build strong shells and skeletons, which effects coral reefs and food webs worldwide.
- Carbonate also dissolves existing calcified structures of organisms at a faster rate in lower pH water, thereby exacerbating the calcification problem.
- These threats to sea life also threaten the economy, since some of the most vulnerable species – clams, crabs, lobsters, mussels, shrimp and scallops – represent half of the $4 billion annual value of all fish harvested in U.S. waters.
- Additionally, sea organisms “without shells, such as anemones and jellyfish, may be especially susceptible to even the smallest changes in ocean pH because their internal pH tends to vary with that of the surrounding seawater. These organisms cannot actively regulate their internal pH as mammals do.”
- Then there are other, less obvious consequences. Lower pH levels means that the ocean will absorb less sound at low frequencies, which makes the oceanic atmosphere noisier. While sonar using mammals might be able to communicate over longer distances, they will have to deal with more background distractions.
Of course, acidification is not the only threat to the health of the ocean. Atmospheric warming, rising sea levels and overfishing are also taking their toll, threatening to disrupt delicate biological processes faster then they can adapt.
One study, for example, suggests that warming will create “dead zones” in the ocean that will be devoid of marine life for up to 2 millennia.