We find carbon everywhere on Earth ─ in trees, rocks, fossil fuels, oceans, and even you! Carbon doesn’t stay in one place, through. Scientists study how carbon moves from one place to another. This is the carbon cycle.
The ocean is a “carbon sink,” which means that it removes CO2 (carbon dioxide) from the atmosphere. The ocean currently absorbs about one-third of the CO2 released by the burning of fossil fuels.
However, beyond a certain level of atmospheric CO2, the ocean can no longer act as a carbon sink without it having a negative impact on marine life. When CO2 dissolves in seawater, it leads to decreased pH levels. The ocean becomes less alkaline. This is referred to as ocean acidification.