Green Glossary: Carbon Sink

A carbon sink is a "reservoir that absorbs or takes up released carbon from another part of the carbon cycle." Carbon behaves in such a systematic manner in four regions of the Earth: the atmosphere, terrestrial biosphere (usually including freshwater systems), oceans, and sediments (including fossil fuels)." This all becomes relevant in an ecological sense when we discover that by absorbing carbon, carbon sinks offset carbon dioxide emissions.

The folks at Wise Geek explain that the process by which a carbon dioxide sink removes carbon from the air is termed "carbon sequestration." They add: "During this processes the carbon is separated and stored while leaving the oxygen. Trees and plants naturally absorb carbon dioxide for photosynthesis, sequestering the carbon and converting it into mass while releasing the oxygen back into the atmosphere."

A common example of a natural carbon dioxide sink is an immature forest. This is because "young vegetation needs significantly more carbon dioxide to build its mass."