Consider the following: on an annual basis,C exchange from photosynthesis is 120 Gt,decomposition is 60 Gt,respiration is 60 Gt,ocean uptake of CO2 is 92 Gt of C,ocean release is 91 Gt C,release of C to the atmosphere from anthropogenic sources (fossil fuel use and land use change)is 6 Gt,and the atmosphere is increasing by 3.2 Gt of C.If terrestrial processes are responsible for the remaining C for net balance of the C cycle,then which of the following is likely?

Question

Quizplus · Accepted Answer

The net increase in atmospheric carbon is 3.2 Gt. The ocean is a net sink of 1 Gt (92 Gt uptake - 91 Gt release). Anthropogenic sources add 6 Gt. Therefore, the terrestrial surface must be a net sink of 1.8 Gt to balance the carbon cycle (6 Gt - 3.2 Gt - 1 Gt = 1.8 Gt).

Consider the Following: on an Annual Basis,C Exchange from Photosynthesis