Carbon balance of the Atmosphere.
Forests and oceans absorb 5 billion ton/year (3 forests and 2 oceans), while human activity adds 9 billion ton/y by burning fossil fuels. Litosphere (rocks and solid hearth) adds 0,1. The result is an average increase of carbon to the atmosphere of 4,1 billion ton/y.
Future trends: oceans will decrease their absorpion capacity because of an increased water temperature; litosphere will increase its emission flux because of permafrost unfreezing.
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