What is Carbon Sequestration?

Carbon sequestration is the process of removing carbon from the atmosphere and storing it in a carbon sink, a fixed molecule in soil, oceans or plants. Because of the amounts of carbon that are stored in soils, small changes in soil carbon content can have major impacts on carbon dioxide levels in the atmosphere.

Impacts of Carbon Sequestration

  • About 25% of our carbon emissions have historically been captured by Earth’s forests, farms and grasslands. Scientists and land managers are working to keep landscapes vegetated and soil hydrated for plants to grow and sequester carbon.
  • As much as 30% of the carbon dioxide we emit from burning fossils fuels is absorbed by the upper layer of the ocean. But this raises the water’s acidity, and ocean acidification makes it harder for marine animals to build their shells. Scientists and the fishing industry are taking proactive steps to monitor the changes from carbon sequestration and adapt fishing practices.

Our Future with Carbon Sequestration

Could soil hold the key to climate change?


Soils contain inorganic carbon (calcium carbonate) and organic carbon (humus), and can be either a source or a sink for atmospheric carbon dioxide depending on how landscapes are managed. Vegetated landscapes are starting to appear as carbon sources instead of sinks in some cases. For example, if wildfire increases in a region, that carbon goes back to the atmosphere when the trees burn. When pests, such as bark beetles, come into an ecosystem, they cause the trees to die, and the trees no longer sequester carbon.

Even living plants reach a limit in their ability to sequester carbon. The process of photosynthesis is closely tied with the availability of water and the availability of nitrogen, both of which are changing due to land uses and rising global temperatures.

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