Climate Change - Carbon Sinks

Carbon sinks are natural systems that suck up and store carbon dioxide from the atmosphere.

The main natural carbon sinks are plants, the ocean and soil. 


Plants grab carbon dioxide from the atmosphere to use in photosynthesis; some of this carbon is transferred to soil as plants die and decompose. 

The oceans are a major carbon storage system for carbon dioxide. 

Marine life also takes up the gas for photosynthesis, while some carbon dioxide simply dissolves in the seawater.

35 billion tonnes of CO2 are produced each year by human activities.

The figure of 33.4 billion metric tonnes of carbon dioxide is for 2010.  

The remaining carbon dioxide is building up in the atmosphere.

 Atmospheric CO2 data and trend

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