In the conversation about climate change, a lesser talked about but still significant phenomenon is ocean acidification. To put it succinctly, this process is where the oceans absorb the mass amounts of carbon dioxide in the air, leading to a series of chemical reactions that result in the acidification of the waters. According to the EPA, the ocean has become 25% more acidic since pre-industrial times. Let's take a closer look at exactly how this happens.
As you might expect, the process begins with carbon dioxide emission from our atmosphere. From there, the oceans absorb a good portion of it. The ocean's surface is like a giant carbon sponge. While this used to be part of the Earth's natural carbon cycle, the quantity of CO2 today is multiple times greater than in pre-industrial times.
From there, the CO2 reacts with the water to form carbonic acid. While it is a weak acid, the vast amount being created causes a significant impact. It then dissociates into bicarbonate ions and hydrogen ions. This reaction is crucial as the increase in hydrogen ions decreases the pH of the water, thus making it more acidic.
Each organism is adapted to suit the environment they are in. As anyone with a pet fish can tell you, animals are susceptible to their water's pH and require a maintained balance to function. Studies show that some fish, such as clownfish, cannot locate homes and identify predators in an acidifying environment.
Also, some hydrogen ions undergo further reactions, bonding with carbonate ions to form bicarbonate ions. Carbonate ions are used by organisms like corals, oysters, and clams to create shells. They need it to build their homes and skeletons. Without carbonate ions, their bodies become weaker and more susceptible to becoming prey.
The net result of these reactions is a decrease in water's pH, a.k .a. ocean acidification. This change in acidity wreaks havoc on the lives of countless marine animals, disrupting food chains and destroying ecosystems. However, we must remember this process is not an isolated incident but part of a bigger painting of climate change. We can mitigate this crisis by addressing the root cause of CO2 emissions and maintain a healthy ocean for future generations.
Daniel Kim (December, 2023)