Although the Paris agreement will represent a step forward, the gap between actual global emissions and those required by science to limit global warming to 2°C is likely to grow.
- Under an optimistic—stronger pledge—scenario, the Paris agreement could achieve up to 50% of the emissions reductions necessary to move the world toward a 2°C pathway.
- If countries that have not yet announced their goals put forward relatively weak pledges, the Paris agreement could close as little as 28% of the gap between business-as-usual and the 2°C pathway.
- The biggest difference between the stronger and weaker pledge scenarios—about 4Gt, or 14% of the needed reductions—is the level of ambition expected from middle-income countries in Eastern Europe, Asia, the Middle East, and South America.
- This analysis includes only emissions mitigation that is not conditional on international finance. International mitigation partnerships should be pursued to narrow the remaining gap.