Taking stock of global progress towards achieving the Paris Agreement requires consistently measuring aggregate national actions and pledges against modelled mitigation pathways1. However, national greenhouse gas inventories (NGHGIs) and scientific assessments of anthropogenic emissions follow different accounting conventions for land-based carbon fluxes resulting in a large difference in the present emission estimates2,3, a gap that will evolve over time. Using state-of-the-art methodologies4 and a land carbon-cycle emulator5, we align the Intergovernmental Panel on Climate Change (IPCC)-assessed mitigation pathways with the NGHGIs to make a comparison. We find that the key global mitigation benchmarks become harder to achieve when calculated using the NGHGI conventions, requiring both earlier net-zero CO2 timing and lower cumulative emissions. Furthermore, weakening natural carbon removal processes such as carbon fertilization can mask anthropogenic land-based removal efforts, with t
The Blue Carbon Accounting Model (BlueCAM) is a tool for tidal restoration projects established under the Tidal Restoration for Blue Carbon method (2022) of the Australian voluntary carbon market. The commentary of Gallagher discussed that BlueCAM did not subtract allochthonous carbon, which is carbon in wetland soils from external sources, either terrestrial or marine sources, from estimated net abatement. This approach was used because all organic carbon preserved in a restored wetland soil, irrespective of its source, is deposited because the wetland was restored, and thus all carbon preserved above the baseline is “additional.” As restoration projects develop, further characterization of different soil carbon fractions as suggested by Gallagher may improve BlueCAM. BlueCAM is transparent, conservative, and importantly is feasible for implementation, as well as being consistent with the Intergovernmental Panel for Climate Change guidelines for National Greenhouse Gas Inventories
Diagnosing anthropogenic carbon emissions: A carbon dioxide checkup of Earth s health phys.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from phys.org Daily Mail and Mail on Sunday newspapers.