Introduction
The Paris Agreement, adopted on December 12, 2015, during the 21st Conference of the Parties (COP21) to the United Nations Framework Convention on Climate Change (UNFCCC), represents a historic international treaty aimed at addressing the global challenge of climate change. With a central goal of limiting the increase in global average temperature to well below 2°C above pre-industrial levels and pursuing efforts to limit the increase to 1.5°C, the Agreement seeks to unite nations in a cooperative framework for climate change mitigation, adaptation, and finance (United Nations, 2015). As of February 2023, 195 members of the UNFCCC are parties to the Agreement, underscoring its near-universal acceptance (Wikipedia, 2025). However, despite its ambitious objectives, the Paris Agreement faces significant challenges in achieving global climate goals. These challenges include disparities in national commitments, enforcement mechanisms, financial and technological barriers, and varying legal frameworks for treaty incorporation across countries.
This article examines the multifaceted challenges of the Paris Agreement in meeting its global climate goals. It delves into the legal mechanisms for treaty-making and incorporation into national law, with a focus on a hypothetical country (referred to as “this country”) to illustrate how international commitments translate into domestic action. The discussion also explores whether this country follows a monist or dualist approach to treaties, the specific provisions of the Paris Agreement that govern state participation, and the relationship between the Paris Agreement and the Vienna Convention on the Law of Treaties (VCLT) of 1969. Finally, it considers how this relationship may inform other countries on entering treaties associated with the Paris Agreement.
The Paris Agreement: Structure and Objectives
The Paris Agreement is built on the foundation of the UNFCCC, adopted in 1992, which established an overarching framework for international cooperation on climate change. Unlike its predecessor, the Kyoto Protocol, which imposed binding emission reduction targets on developed countries, the Paris Agreement adopts a more flexible approach through Nationally Determined Contributions (NDCs). Under Article 4 of the Paris Agreement, each party is required to prepare, communicate, and maintain successive NDCs that represent their highest possible ambition in mitigating greenhouse gas emissions (United Nations, 2015). These contributions are not legally binding in terms of specific targets, but the procedural obligations—such as reporting and reviewing progress—are mandatory, creating a hybrid structure of binding commitments and voluntary action (Carbon Brief, 2015).
The Agreement’s primary objectives are outlined in Article 2, which emphasizes strengthening the global response to climate change through temperature limitation, adaptation to climate impacts, and ensuring financial flows consistent with low greenhouse gas emissions and climate-resilient development (United Nations, 2015). Additionally, Articles 9, 10, and 11 address financial assistance, technology transfer, and capacity-building, respectively, to support developing countries in meeting their climate goals. Despite these comprehensive provisions, the Paris Agreement struggles with implementation due to varying national capacities, political will, and legal frameworks.
Challenges in Achieving Global Climate Goals
1. Disparities in National Commitments and Ambition
One of the primary challenges facing the Paris Agreement is the disparity in the ambition and implementation of NDCs across countries. While the Agreement encourages parties to enhance their contributions every five years under Article 4(9), there is no mechanism to enforce the stringency of these targets. Studies indicate that current NDCs, even if fully implemented, are insufficient to meet the 1.5°C or 2°C targets, potentially leading to a temperature rise of 2.4–3.5°C by 2100 (UN Environment Programme, 2022). Major emitters, such as the United States, which withdrew from the Agreement in 2020, rejoined in 2021, and announced another withdrawal in 2025, highlight the volatility of political commitment (Wikipedia, 2025). Such fluctuations undermine global efforts and create uncertainty for collaborative climate action.
Developing countries, while contributing less to historical emissions, face challenges in balancing economic growth with emission reductions. The principle of “common but differentiated responsibilities” under Article 2(2) of the UNFCCC, reiterated in the Paris Agreement, acknowledges these disparities but does not provide enforceable solutions to bridge the gap between developed and developing nations’ contributions.
2. Enforcement and Accountability Mechanisms
Unlike traditional treaties with punitive measures, the Paris Agreement relies on a transparency framework under Article 13 to promote accountability. Parties are required to submit biennial transparency reports on their progress toward NDCs, which are subject to technical expert review. However, the lack of sanctions for non-compliance raises concerns about the Agreement’s effectiveness. As Voigt (2023) notes, while climate litigation at international and national levels has increased, leveraging the Paris Agreement in legal proceedings remains complex due to its non-binding nature on specific targets (Voigt, 2023). This “soft law” approach, while fostering broader participation, risks diluting accountability.
3. Financial and Technological Barriers
Financial support and technology transfer are critical to the success of the Paris Agreement, particularly for vulnerable nations. Article 9 mandates developed country parties to provide financial resources to assist developing countries with mitigation and adaptation, with a collective goal of mobilizing $100 billion annually by 2020, extended to 2025. However, reports indicate that this target has not been consistently met, with funding often falling short of commitments (OECD, 2022). Moreover, access to clean energy technologies remains limited in many regions, hindering the transition to low-carbon economies as envisioned under Article 10.
4. Legal and Institutional Challenges
The incorporation of international treaties like the Paris Agreement into national law varies widely due to differences in legal systems. The following sections explore these challenges by examining the legal framework for treaty-making in a hypothetical country and the broader implications for global adherence to the Agreement.
Legal Framework for Treaty-Making in “This Country”
To understand how international commitments like the Paris Agreement are operationalized, it is necessary to examine the legal mechanisms for entering treaties in a specific national context. For the purposes of this analysis, “this country” serves as a representative case to highlight the procedural and legal intricacies of treaty incorporation. Although specific details about “this country” are not provided in the prompt, a generic framework based on common state practices will be applied, with the assumption that it is a UNFCCC member state and a signatory to the Paris Agreement.
Process of Entering Treaties
The Paris Agreement, under Article 20, stipulates that it is open for signature by states and regional economic integration organizations that are parties to the UNFCCC. Signature indicates intent to be bound, while ratification, acceptance, or approval, as outlined in Article 21, finalizes a state’s consent to be legally bound by the treaty. The Agreement entered into force on November 4, 2016, after at least 55 parties accounting for at least 55% of global greenhouse gas emissions deposited their instruments of ratification (United Nations, 2015).
In “this country,” the process of entering treaties typically involves several stages, reflecting international norms. First, the executive branch, often through the head of state or government, signs the treaty to express preliminary commitment. Following signature, the treaty must be submitted to the national legislature for approval or ratification, depending on the country’s constitutional requirements. While the Paris Agreement does not specify domestic procedures for ratification, it implies under Article 27 that states must adhere to their internal legal processes to ensure compliance with treaty obligations.
Monist or Dualist Approach
Countries adopt either a monist or dualist approach to the incorporation of international law into domestic law. In a monist system, international treaties automatically become part of national law upon ratification, without the need for additional legislation. In contrast, a dualist system requires separate legislative action to translate treaty provisions into domestic law. For the purposes of this analysis, it is assumed that “this country” follows a dualist approach, a common framework among many states, particularly those with a common law tradition.
In a dualist system, after ratification of the Paris Agreement, “this country” would need to enact specific legislation to implement its commitments, such as laws regulating greenhouse gas emissions or establishing carbon pricing mechanisms in line with its NDCs under Article 4. This process can be time-consuming and subject to political resistance, potentially delaying compliance with international obligations. For instance, if the national legislature prioritizes economic concerns over environmental targets, enabling legislation may be weakened or deferred, undermining the country’s ability to meet its climate goals.
Incorporation into National Law
In “this country,” the incorporation of the Paris Agreement into national law would typically involve drafting and passing domestic statutes that align with the treaty’s provisions. This may include creating regulatory bodies to monitor emissions, establishing funding mechanisms for adaptation projects as per Article 9, or setting legal standards for renewable energy adoption under Article 10. The dualist approach ensures that international commitments are adapted to the domestic legal context, but it also risks inconsistency if national laws do not fully reflect the treaty’s objectives. For example, if “this country” enacts lenient emission standards despite ambitious NDCs, it may technically comply with procedural reporting under Article 13 but fail to contribute meaningfully to global climate goals.
Moreover, judicial interpretation plays a role in dualist systems. National courts in “this country” may need to reconcile domestic laws with international obligations, especially in cases of climate litigation inspired by the Paris Agreement. As Voigt (2023) highlights, the Agreement’s influence in domestic legal proceedings is growing, but its non-binding elements limit its enforceability (Voigt, 2023).
The Paris Agreement and the Vienna Convention on the Law of Treaties (1969)
Relationship with the VCLT
The Vienna Convention on the Law of Treaties (VCLT), adopted in 1969, is a foundational instrument in international law that codifies the rules governing the formation, interpretation, and termination of treaties. While the Paris Agreement does not explicitly state whether it is a party to the VCLT, it operates within the broader framework of international treaty law as established by the VCLT. The VCLT applies to treaties between states, and since the Paris Agreement is a multilateral treaty negotiated under the UNFCCC, its creation, entry into force, and binding nature are implicitly governed by VCLT principles (United Nations, 1969).
For instance, the VCLT’s Article 11 on the means of expressing consent to be bound aligns with the Paris Agreement’s provisions on signature and ratification under Articles 20 and 21. Similarly, the VCLT’s Article 26, which enshrines the principle of pacta sunt servanda (agreements must be kept), reinforces the legal obligation of parties to the Paris Agreement to adhere to their commitments, even if specific targets within NDCs remain non-binding. Furthermore, the VCLT’s rules on interpretation (Articles 31–33) guide how ambiguities in the Paris Agreement, such as the discretionary nature of financial contributions under Article 9, are resolved in international dispute resolution or advisory opinions.
Implications for Other Countries
The relationship between the Paris Agreement and the VCLT provides valuable insights for other countries on how to properly enter into treaties related to the Agreement. First, adherence to VCLT principles ensures that states follow internationally recognized procedures for treaty-making, such as negotiation, signature, and ratification, as seen in the Paris Agreement’s entry into force under Article 21. Countries must ensure that their domestic processes align with these steps to avoid legal challenges to their participation.
Second, the VCLT’s emphasis on good faith (Article 26) encourages countries to commit to the Paris Agreement with genuine intent to fulfill their obligations. This is particularly relevant for states with dualist systems, where domestic incorporation may lag behind international commitments. By referencing the VCLT, countries can establish robust legal frameworks to translate NDCs into enforceable national policies, thereby enhancing accountability.
Finally, the VCLT’s provisions on reservations (Articles 19–23) are instructive for countries considering limited participation in treaties like the Paris Agreement. While the Agreement itself prohibits reservations under Article 27, understanding VCLT rules on treaty flexibility can guide states in negotiating future climate accords or protocols under the UNFCCC framework. For non-parties or states reconsidering membership, such as Iran or the United States, the VCLT offers a legal pathway to re-engage with the Paris Agreement through formal accession or re-ratification processes.
Broader Challenges and Future Directions
Beyond the legal intricacies of treaty-making, the Paris Agreement faces systemic challenges that require innovative solutions. One such challenge is the integration of non-state actors, such as corporations and civil society, into climate action. While the Agreement focuses on state parties, subnational and private sector initiatives can complement NDCs, especially in countries with federal or decentralized systems. Encouraging such multi-level governance could address implementation gaps, though it requires coordination to avoid fragmentation.
Another area of concern is the adequacy of adaptation frameworks under Article 7. With climate impacts intensifying, particularly for small island developing states and least developed countries, the Paris Agreement’s emphasis on resilience must be matched with concrete support mechanisms. Scaling up the Green Climate Fund and other financial instruments remains critical to achieving a balance between mitigation and adaptation.
Geopolitical tensions also threaten the Agreement’s success. The re-withdrawal of the United States in 2025, as reported in various sources, exemplifies how domestic politics can destabilize international cooperation (Wikipedia, 2025). Building resilience into the Paris Agreement framework—through diversified leadership and decentralized implementation—could mitigate the impact of such exits. Furthermore, enhancing the role of international courts and human rights bodies in climate litigation, as discussed by Voigt (2023), could provide an additional layer of accountability.
Conclusion
The Paris Agreement stands as a landmark in international climate governance, uniting nearly all nations under a shared commitment to combat climate change. However, achieving its global climate goals remains fraught with challenges, including disparities in national ambition, weak enforcement mechanisms, financial and technological barriers, and varying legal frameworks for treaty incorporation. By examining the legal processes in a hypothetical dualist country (“this country”), this article has highlighted the complexities of translating international obligations into domestic action, underscoring the need for robust legislative and judicial mechanisms to support the Agreement’s objectives.
The relationship between the Paris Agreement and the Vienna Convention on the Law of Treaties (1969) further illuminates the importance of adhering to established norms of international law in treaty-making. For other countries, this relationship serves as a reminder to align domestic processes with global standards, ensuring that commitments under the Paris Agreement are both legally sound and practically implementable. As the world approaches critical deadlines for climate action, addressing these challenges through enhanced cooperation, innovative financing, and strengthened accountability will be essential to realizing the transformative potential of the Paris Agreement.
References
- Carbon Brief. (2015). Explainer: The legal form of the Paris climate agreement. Retrieved from Carbon Brief website.
- OECD. (2022). Climate Finance Provided and Mobilised by Developed Countries in 2016-2020. OECD Publishing.
- United Nations. (1969). Vienna Convention on the Law of Treaties. United Nations Treaty Series, vol. 1155, p. 331.
- United Nations. (2015). Paris Agreement. Adopted at the 21st Conference of the Parties to the UNFCCC. Retrieved from UNFCCC website.
- UN Environment Programme. (2022). Emissions Gap Report 2022. UNEP.
- Voigt, C. (2023). The power of the Paris Agreement in international climate litigation. Review of European, Comparative & International Environmental Law, 32(3), 345-356. doi:10.1111/reel.12514.
- Wikipedia. (2025). Paris Agreement. Retrieved from Wikipedia website.
