Economic value of improved quantification in global sources and sinks of carbon dioxide

On average, about 45 per cent of global annual anthropogenic carbon dioxide (CO2) emissions remain in the atmosphere, while the remainder are taken up by carbon reservoirs on land and in the oceans-the CO2 'sinks'. As sink size and dynamics are highly variable in space and time, cross-verification of reported anthropogenic CO2 emissions with atmospheric CO2 measurements is challenging. Highly variable CO 2 sinks also limit the capability to detect anomolous changes in natural carbon reservoirs. This paper argues that significant uncertainty reduction in annual estimates of the global carbon balance could be achieved rapidly through coordinated up-scaling of existing methods, and that this uncertainty reduction would provide incentive for accurate reporting of CO 2 emissions at the country level. We estimate that if 5 per cent of global CO2 emissions go unreported and undetected, the associated marginal economic impacts could reach approximately US$20 billion each year by 2050. The net present day value of these impacts aggregated until 2200, and discounted back to the present would have a mean value exceeding US$10 trillion. The costs of potential impacts of unreported emissions far outweigh the costs of enhancement of measurement infrastructure to reduce uncertainty in the global carbon balance.