Analytical Error Estimate for the Ocean and Land Uptake of CO2 Using delta(13)CObservations in the Atmosphere

摘要

The quantity and quality of atmospheric data pertaining to the global carboncycle have improved to an extent that more realistic error estimates can now be attempted for regional sources and sinks of CO2 derived from such data. We present here a detailed error analysis of the land and ocean fluxes inferred by Ciais et at. Because the analytic expression for the fluxes is known explicitly, it is possible to use an analytical propagation of errors. In this manner, we quantify the main uncertainities associated with the three principle parameters of the model: the discrimination against (13)C by plant photosynthesis and the ocean and land isotopic disequilibria. This requires a physical, and thus partly subjective, estimate of the uncertainty of each of the three parameters.