Climate pledges under Paris Agreement cover what fraction of greenhouse gas…

Under the Paris Agreement (2015), countries submit voluntary climate pledges called Nationally Determined Contributions (NDCs). International bodies such as UNEP and the UNFCCC Secretariat periodically compare the sum of these pledges against the emissions cuts a well-below-2°C pathway actually requires, producing an ‘emissions gap’ assessment.

The UNEP Emissions Gap Report (2017) and UNEP's related 2018 assessment found that the NDCs submitted under the Paris Agreement deliver only about one-third of the emissions reductions needed to stay on a well-below-2°C pathway — equivalently, UNEP concluded nations would need to roughly triple their pledged ambition to close the remaining gap. This shortfall is why the Agreement built in a five-year ‘ratchet’ cycle, requiring each new round of NDCs to be more ambitious than the last.

Why the other fractions do not fit:

• 2/3 would mean pledges already cover most of the required cuts, contrary to UNEP's repeated finding that nations must roughly triple their pledged ambition to reach the well-below-2°C pathway.

• 1/2 assumes an even split between what is pledged and what is missing, but the quantitative UNEP/UNFCCC synthesis of NDCs found a considerably larger shortfall than an even half.

• 3/4 would mean pledges nearly close the gap on their own, which conflicts with the very rationale for the Agreement's five-year ratchet mechanism of progressively strengthened NDCs.