Facts4Paris: if every country matches the US pledge, in 2025 world emissions will be 6% higher than they were in 2010.
If countries were to choose targets comparable with those of the US (where comparabability is determined either according to a 'common but differentiated per-capita convergence' scheme or to an 'equal cumulative per-capita' approach) world emissions would be 6% higher in 2025 than they were in 2010. For a least-cost 2°C trajectory, world emissions need to be 15% below 2010 emissions, or 10% above 1990 levels by 2025. Check out www.mitigation-contributions.org to explore the outcomes of such calculations for a G20 country of your choice using different comparability approaches.
Source: See our new Nature Climate Change paper for methods and data.