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The Threat of Ocean Acidification

The Threat of Ocean Acidification

Figure 1. Ocean acidification (, 2022).


More than 70% of the surface of our world is covered by oceans, which is essential for regulating the temperature, sustaining a variety of ecosystems, and preserving life. Ocean acidification, a developing issue, is casting a shadow on the health of these enormous bodies of water. Approximately 525 billion tons of CO2 has been absorbed by the ocean from the atmosphere, or 22 million tons each day at the moment (Bennet, 2018). The behavior of organisms that do not produce calcium can also be impacted by these changes in ocean chemistry. More acidic conditions reduce a fish's capacity to detect predators. The entire food chain may be in danger if these organisms are threatened (National Oceanic and Atmospheric Administration, n.d.).

What is Ocean Acidification?

The combustion of fossil fuels and changes in land use have led to an increase in the atmospheric concentration of carbon dioxide (CO2) for more than 200 years (National Oceanic and Atmospheric Administration, n.d.). About 30% of the CO2 that is released into the atmosphere is absorbed by the ocean, and as atmospheric CO2 levels rise, so do ocean CO2 levels. Ocean acidification is the term for a long-term decline in the ocean's pH, which indicates a higher acidity (Lai, 2022). Hydrogen ions (H+), a type of chemical proton, are mostly responsible for aggravating ocean water's acidity. The water becomes more acidic as hydrogen ion concentrations increase. Water and carbon dioxide can mix to form carbonic acid, which can further split into hydrogen ions and increase the acidity of the water. The pH level of ocean water will naturally change depending on seasonal and regional conditions. For instance, due to carbon dioxide dissolving easily in colder temperatures, the pH is typically lower in cold water. Ocean acidification is

thus observed to be particularly prevalent in the polar areas.

Figure 2. Increase of CO2 levels in the ocean (International Atomic Energy Agency, 2022).

The Effects of Ocean Acidification

Marine ecology is endangered by ocean acidification. Numerous marine creatures are particularly vulnerable in an ocean that is more acidic because acidic water eliminates carbonate ions, an essential component of shells and skeletons (Lai, 2022). Carbonate ions play a crucial role in the formation of structures like coral skeletons and seashells (National Oceanic and Atmospheric Administration, n.d.). For calcifying animals including oysters, clams, sea urchins, shallow water corals, deep sea corals, and calcareous plankton, declines in carbonate ions can make creating and sustaining shells and other calcium carbonate structures problematic (National Oceanic and Atmospheric Administration, n.d.). Ocean acidification may cause changes in marine species' growth, development, abundance, and survival. Large undersea structures known as coral reefs, which are made of the coral-like skeletons of colonial marine invertebrates, are immensely vital to our planet since they house one of its most biodiverse ecosystems (Lai, 2022). It is crucial to conserve them because they provide protection to coastlines and serve as supplies of nitrogen and other nutrients for marine food systems. Unprecedented rates of mass coral bleaching , which are primarily brought on by ocean acidification, are worrisome. Even though fish do not possess shells, the impacts of acidification still affect them. A fish's cells frequently absorb carbonic acid to bring the pH of the seawater into harmony with the lower pH of the surrounding water (Bennet, 2018). This causes acidosis, a condition where the pH of the fish's blood fluctuates. A fish must work its body into overdrive to restore its chemistry because it is likewise pH sensitive. It will use more energy to remove the additional acid from its blood in order to accomplish this. This drains the energy a fish needs for other activities like digestion, swimming quickly to fend off predators or obtain food, and reproduction.

Figure 3. Branching corals in acidic water (Plaisance, n.d.).

What can be done now?

The best strategy to slow down ocean acidification is to address climate change by finding ways to drastically cut back on the consumption of fossil fuels (Union of Concerned Scientists, 2019). We can greatly lessen the impact to marine ecosystems if we significantly decrease our emissions that contribute to global warming and we limit future warming. We may all help by lessening our personal environmental impact. To lessen our carbon footprint, we can buy locally produced goods, recycle our waste, use fewer plastics, choose renewable energy to power our homes, and if possible, refrain from using fossil fuel-powered vehicles (Lai, 2022). We can contribute to maintaining the well-being of our oceans by making small, gradual changes.


Bennett, J. (2018, December 18). Ocean Acidification. Smithsonian Ocean.

Lai, C. (2022, July 21). What Is Ocean Acidification?

National Oceanic and Atmospheric Administration. (2021, February 26). What is Ocean

Acidification?; National Oceanic and Atmospheric


Revolution. (2013, October 30). Solutions | Revolution. Revolution |.

Union of Concerned Scientists. (2019, January 30). CO2 and Ocean Acidification | Union of

Concerned Scientists.; Union of Concerned Scientists.

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