全球变化知识资源中心

The wide spectrum of national priorities and attendant climate positions among parties to the United Nations Framework Convention on Climate Change (UNFCCC) have been a hallmark of international climate negotiations. The Paris Agreement was lauded as a landmark step toward global climate action because it represented a consensus of more than 190 countries. Taken in a vacuum, however, the agreement masks important differences in climate positions and capabilities among its signatory parties. Because the nationally determined contributions (NDCs) are the key instruments of post-Paris climate commitments, analysis of salient themes revealed in the NDCs is critical to understanding the dynamics of climate negotiations. We present a quantitative content analysis of 165 NDCs to investigate convergence and divergence in the positions of UNFCCC parties and party groupings. We use a hierarchical cluster analysis based on references to key terms of climate discourse to measure the internal cohesion of traditional party groupings and emergent coalitions. Our analysis shows that the greatest difference in NDC content occurs between the Annex I (composed mainly of the Umbrella Group, European Union, Environmental Integrity Group, and unaffiliated parties) and non-Annex I countries. Furthermore, we show that the landscape of climate priorities is considerably more complex than a binary Annex I-non-Annex I divide, as indicated by convergence on climate action between large developing economies and smaller, less developed, active negotiator groupings. Understanding congruence and disparities among NDCs, and their potential to promote cooperation or division among parties, will be critical to developing equitable and sustainable long-term climate solutions.