Carbon sink
Topic: Climate Change: Causes, Evidence and the Global Response · NCERT: Class 11, Ch 11 "World Climate and Climate Change"
Meaning
A carbon sink is anything that absorbs more CO2 than it releases. Forests, oceans and soils are the main sinks. Plants take in CO2 to grow, and seawater dissolves it. Oceans take up about a quarter of human emissions and land about 30%. When forests are cut, the sink weakens and more CO2 stays in the air. NCERT says CO2 takes 20–50 years to adjust to changes in sources and sinks, but much CO2 stays in the air for centuries.
Example
India's climate pledge (NDC) aims to create an extra forest carbon sink of 2.5–3 billion tonnes of CO2-equivalent by 2030. It plans to do this through more forest and tree cover, for example under the Green India Mission.
Don't confuse with
- Carbon source: anything that releases more CO2 than it absorbs, such as burning fossil fuels or a cleared forest.
- Carbon capture and storage (CCS): a technology that captures CO2 from factories or the air and stores it underground. A carbon sink is usually natural.
Related concepts
- Greenhouse effect
- Greenhouse gases
- Global warming potential
- Methane
- Nitrous oxide
- Chlorofluorocarbons
- Tropospheric ozone
- Climate sensitivity
- Carbon budget