What is ocean acidification?
Ocean acidification (OA) is the absorption of carbon dioxide into seas around the world. Much of the carbon dioxide comes from the acts of humans since the beginning of the Industrial Revolution. When carbon dioxide (CO2) is dissolved in seawater (H2O), it creates carbonic acid (H2CO3). The carbonic acid immediately dissolves into H+ ions (acidic), that, eventually, increase the pH of oceans, and biocarbonate (HCO3-, basic). Almost all types of marine life are affected by this
catastrophe in some way, yet they aren’t the only ones being hit. Shellfish, oysters, and other calcifying organisms are the foundation of many fishing businesses in America. Due to OA, the productivity of these corporations have declined dramatically since 2005 (PMEL).
It can’t be that bad, right?
Wrong. Most marine ecosystems are being constantly damaged since they are gaining carbon dioxide directly from the ocean. Bill Dewey of Taylor Shellfish Farms says that, “Because of natural tide and wave patterns, the Pacific Northwest Coast has been hit hardest, with corrosive water being brought up controlled for commercial purposes. But all of a sudden, the oyster larvae began dying by the billions (Sreenivasan). The acidic water from the Pacific Ocean that was being pumped into the hatcheries was to blame. The corrosive waters destroyed the oyWrong. Most marine ecosystems are being constantly damaged since they are gaining carbon dioxide directly from the ocean. Bill Dewey of Taylor Shellfish Farms says that, “Because of natural tide and wave patterns, the Pacific Northwest Coast has been hit hardest, with corrosive water being brought up ster shells before they could begin to form causing the larvae to die immediately (Sreenivasan “Ocean Acidification’s”).
Alright, so it’s bad. Any other animals affected?
Phytoplankton and zooplankton have the same problems that oysters do. They have trouble creating enough calcium carbonate to support themselves. Most calcifying organisms in acidic waters do. This can have a strong negative impact on the marine food chain due to the fact that phytoplankton and zooplankton are the
basis for the entire food chain in oceans. Coral reefs are also heavily affected by the dropping pH levels of oceans because they are unable to grow their carbonate skeletons due to the higher carbon dioxide rates. Also, the increase in carbon dioxide led to warmer water temperatures, yet corals are more accustomed to cooler waters. This causes a process called bleaching to occur. Other affected animals such as cephalopods (i.e. squid) are sensitive to the increase in carbon dioxide because their bodies require large amounts of oxygen to the blood for swimming which is diminished by lowered blood pH levels (“Other Marine Animals?”). Yet there are some marine mammals that have not been pressured as much as their sea brethren. Mammals (i.e. whales, seals) are not directly affected because they breathe air, yet in the long run they will be impacted due to the changes in food webs (Hood).
By: Kathryn Samuel
A coral reef exposed to increased levels of carbon dioxide which led to bleaching
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