carbon sink

carbon cycle

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July 17, 2026

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A carbon sink is a location, such as the ocean, soil, or forest, that stores carbon, particularly carbon dioxide. These sinks are crucial components of the carbon cycle, which describes how carbon atoms continually travel from the atmosphere to the Earth and then back into the atmosphere.123

Human activities, like burning fossil fuels, release carbon into the atmosphere, increasing carbon dioxide concentrations and contributing to global warming. Natural processes, such as photosynthesis, allow terrestrial ecosystems to absorb carbon dioxide, with forests acting as significant carbon sinks. The ocean is the largest carbon sink, holding far more carbon dioxide than the atmosphere. However, environmental changes like drought can reduce the effectiveness of these natural sinks.21

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carbon sequestration
Carbon sources and carbon sinks
…Earth’s atmosphere are known as carbon sinks. For example, deforestation is a source of carbon emission into the atmosphere, but forest regrowth is a form of carbon sequestration, with the forests themselves serving as carbon sinks. Carbon is transferred naturally from the atmosphere to terrestrial carbon sinks through photosynthesis; it…
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…Earth’s atmosphere are known as carbon sinks. For example, deforestation is a source of carbon emission into the atmosphere, but forest regrowth is a form of carbon sequestration, with the forests themselves serving as carbon sinks. Carbon is transferred naturally from the atmosphere to terrestrial carbon sinks through photosynthesis; it…
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climate change
Tectonic activity
(A carbon sink is any process that removes carbon dioxide from the atmosphere by the chemical conversion of CO₂ to organic or inorganic carbon compounds.) Carbonic acid, formed from carbon dioxide and water, is a reactant in dissolution of silicates and other minerals. Weathering rates are…
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(A carbon sink is any process that removes carbon dioxide from the atmosphere by the chemical conversion of CO₂ to organic or inorganic carbon compounds.) Carbonic acid, formed from carbon dioxide and water, is a reactant in dissolution of silicates and other minerals. Weathering rates are…
Read More

global warming
Carbon dioxide
…oceanic processes also act as carbon sinks. One such process, called the “solubility pump,” involves the descent of surface seawater containing dissolved CO₂. Another process, the “biological pump,” involves the uptake of dissolved CO₂ by marine vegetation and phytoplankton (small free-floating photosynthetic organisms) living in the upper ocean or by…
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…oceanic processes also act as carbon sinks. One such process, called the “solubility pump,” involves the descent of surface seawater containing dissolved CO₂. Another process, the “biological pump,” involves the uptake of dissolved CO₂ by marine vegetation and phytoplankton (small free-floating photosynthetic organisms) living in the upper ocean or by…
Read More