Ocean acidification refers to the process by which the pH level of Earth's oceans decreases due to the absorption of excess atmospheric carbon dioxide (CO2). As CO2 is emitted into the atmosphere from human activities, such as burning fossil fuels and deforestation, a significant portion of it is absorbed by the oceans. When CO2 dissolves in seawater, it reacts with water to form carbonic acid, which dissociates into bicarbonate and hydrogen ions.
