Many countries have implemented national climate policies to accomplish pledged Nationally Determined Contributions (NDCs) and contribute to the Paris Agreement's temperature objectives. This study uses a public policy database and multi-model scenario analysis to show that current policies leave a significant emissions gap (22.4–28.2 GtCO₂eq by 2030) compared to pathways aligning with the well-below 2°C and 1.5°C goals. Full NDC implementation would reduce this gap by a third, highlighting both implementation and ambition gaps. Accelerated renewable technology implementation and efficiency improvements are crucial, particularly in emerging and fossil fuel-dependent countries.

Mark Roelfsema, Heleen L van Soest, Mathijs Harmsen, Detlef P van Vuuren, Christoph Bertram, Michel den Elzen, Niklas Höhne, Gabriela Iacob, Volker Krey, Elmar Kriegler, Gunnar Luderer, Keywan Riahi, Falko Ueckerdt, Jacques Després, Johannes Emmerling, Stefan Frank, Oliver Fricko, Matthew Gidden, Florian Humpenöder, Daniel Huppmann, Shinichiro Fujimori, Kostas Fragkiadakis, Keii Gi, Kimon Keramidas, Alexandre C Köberle, Lara Aleluia Reis, Pedro Rochedo, Roberto Schaeffer, Ken Oshiro, Zoi Vrontisi, Wenying Chen, Gokul C Iyer, Jae Edmonds, Maria Kannavou, Kejun Jiang, Ritu Mathur, George Safonov, Saritha Sudharmma Vishwanathan