Designing an Atmospheric Monitoring Network to Verify National CO 2 Emissions

To achieve net-zero carbon emissions by 2050, it is vital to prioritize climate action and monitor the progress of policies with accurate emission estimates. As CO 2 emission estimates can be independently verified using atmospheric CO 2 measurements, the need for optimal CO 2 monitoring networks has increased. This study proposed an experimental method for designing national-scale atmospheric CO 2 monitoring networks. We used gridded data for fossil fuel CO 2 emissions, facilitating the selection of emission grids as potential monitoring sites. First, we determined the appropriate number of CO 2 monitoring sites, which increased in proportion to the magnitude and variability of CO 2 emissions within the region. Subsequently, the emission grids corresponding to the region were arranged in descending order of emissions. Grids were then selected at regular intervals as potential monitoring sites, aligning with the predetermined number of sites. This selection process ensured that monitoring sites were evenly distributed, ranging from areas with high emissions to those with lower emissions. Lastly, as a verification step to assess the suitability of this potential network, a transport model simulating meteorological conditions was employed to evaluate its coverage to detect the influence of CO 2 emissions. This method was applied to South Korea, and 96 candidate monitoring sites were created. The optimal CO 2 monitoring network distributed evenly across South Korea could evaluate variations in CO 2 emissions. The simple monitoring network design method proposed in this study can accelerate the installation of a national CO 2 monitoring network, ultimately enabling the verification of CO 2 emissions and supporting climate policies.