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Image of palm trees against the backdrop of a cityscape by Nodar Chernishev via Canva

Affirming Subnational Diplomacy via Paris: California’s Climate Leadership

Dec 1, 2023


Note from the CPD Blog Manager: Relevant research in this blog received the support of the Research Center in Political Science, University of Minho, through national funds granted by the Portuguese Foundation for Science and Technology and the Portuguese Ministry of Education and Science (UIDB/CPO/00758/2020 & UI/BD/152791/2022). 

As patterns of global agency are no longer limited to unitary structures, California has been pointed out as a prominent case of global climate leadership. Whereas the role of regional governments in traditional diplomacy has been to reflect the guidelines of their national state, a more polycentric climate regime gives space for regional authorities to use their self-governing capacities to pursue their own subnational climate diplomacy strategy towards a shared goal.

Although states remain in the spotlight as central parties of the United Nations Framework Convention on Climate Change, the deterioration of monocentric (i.e., action by the state as a unitary power) arrangements proposed in Kyoto led the Paris Agreement to a central acknowledgment: if global climate governance is to achieve a successful functioning, a more polycentric approach favoring societal “self-coordination” by all sorts of actors is essential. Nonetheless, the encouragement of new forms of governing triggered by a large-scale global challenge such as climate change gives an opportunity for a wide set of actors to position themselves as agents of climate governance or possible leaders. Given this formal action space, one may also spot a functional breach in conventional diplomacy which was long suffering from cracks.

In the absence of a governmental central authority at the global level to provide global public goods, self-organizing and functional dynamics by governance agents interacting beyond inter-state regimes may get around the difficulties of spatially defined jurisdictions. Although dynamics of self-governance are embedded in larger and broader contexts beyond the climate agenda, subnational climate diplomacy represents the affirmation of a political position in climate governance that may anticipate (i.e., move first), bypass (i.e., set contrary standards), or surpass (i.e., set higher ambitions) in comparison with parent’s state climate standards.

Overall, California’s diplomacy efforts have been a significant asset in affirming its climate leadership in the Paris Agreement.

Despite being non-party stakeholders of the Paris Agreement, many regional actors have been following cities’ example and are largely expanding their initiatives of domestic action that are actively reinforced by external climate diplomacy. By setting their own mitigation and adaptation climate action plans, both internally and externally, in the execution of climate targets aligned with Paris’ goals, regional governments in federal and decentralized systems are using their competencies to perform self-governance within a favorable polycentric context that is recognized by the climate regime. An illustration of this reality is presented by the State of California, which has been evidenced as a full-fledged climate agent and an autonomous subnational diplomacy actor in global climate governance. With or without Washington’s support, California has projected itself as an expert in climate matters. By sharing best practices, gaining support for its initiatives and building a worldwide network of like-minded peers, California has made use of its legislative space of functional autonomy (in climate policy and international agency) to position itself as a global climate leader.

During the last decades, California has deployed its own tools and mechanisms to fight against climate change, noticing the potential of diplomacy efforts to achieve its internal climate ambitions through bilateral and multilateral climate agreements with foreign partners. California’s early projection goes back to Governor Schwarzenegger and the Global Warming Solutions Act of 2006, the cap-and-trade program with Québec, and the Regions of Climate Action (R20) network, among other initiatives. Yet, one may point out that its autonomous functional agency in climate governance was finally proclaimed when its climate strategy led by Governor Jerry Brown bypassed President Trump’s withdrawal from the Paris Agreement. From here, the U.S. Climate Alliance was established, America’s Pledge, Under2Mou, Regions4, along with many other coalitions, multilateral and bilateral agreements that finally affirmed California’s climate actorness globally and vis-à-vis the U.S.

With a settled role as a climate leader in the performance of self-governance beyond state action, California’s commitment to the Paris Agreement was no surprise to close followers. A brief review of California’s climate policies demonstrates that it is indeed implementing key provisions of the Paris Agreement in its own jurisdiction. As an example, the AB32 Scoping Plan (updated every five years), California’s Adaptation Strategy (2018), or the State Implementation Plans (SIP’s) in line with California’s Greenhouse Gas Emissions Inventory Program (CARB) support Articles 4.1, 4.2., 4.4., 4.9, and 4.19 from the treaty on emission reductions and reporting. Nonetheless, as the Agreement comprises a two-level matrix of climate action between the domestic and international spheres, this American state also evidences compliance with the Agreements premises among which, Articles 6.1., 6.4., 6.8., 7.1., 7.5, 7.7., 10.2. concerning external cooperation on implementing emission targets, cooperation on adaptation policies, or cooperation on good practices.

Overall, California’s diplomacy efforts have been a significant asset in affirming its climate leadership in the Paris Agreement. By engaging with international partners on various climate domains the state increases (1) its capacity to implement domestic policy ambitions on climate action but also (2) its influence over the course of climate governance as it can change the behavioral patterns of its followers.

It is undeniable that California has made its case as an actor of local implementation and of global-reaching influence in achieving global shared goals. Ultimately, the affirmation of subnational diplomacy through a more polycentric climate context is a direct reflection of broader debates on a structural and system-wide fragmentation that is taking place at the global level through contention, competition and collaboration governance dynamics


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