Introduction
The Paris Agreement, adopted in 2015 under the United Nations Framework Convention on Climate Change (UNFCCC), represents a landmark international treaty aimed at combating global climate change through cooperative efforts among nations. Its primary objective is to limit the rise in global average temperature to well below 2°C above pre-industrial levels, with an aspirational goal of 1.5°C (UNFCCC, 2015). This agreement, signed by 196 parties and ratified by 195 as of 2023, has been hailed as a critical step forward in addressing the urgent threat of climate change. However, the challenges in achieving its ambitious goals are multifaceted, spanning political, economic, legal, and social dimensions. This article explores these challenges in depth, focusing on the structural and practical barriers to the successful implementation of the Paris Agreement. Additionally, it examines the legal frameworks governing treaty participation, specifically how a country can enter into such treaties under international and national law, the monist or dualist approaches to treaty incorporation, and the relevance of the Vienna Convention on the Law of Treaties (VCLT) of 1969 to the Paris Agreement. For contextual clarity, this analysis will assume a hypothetical country, referred to as “Country X,” to illustrate the legal processes and challenges related to treaty participation.
The Paris Agreement and Global Climate Goals
The Paris Agreement, adopted on December 12, 2015, during the 21st Conference of the Parties (COP21) to the UNFCCC, establishes a framework for global climate action through Nationally Determined Contributions (NDCs). These NDCs are voluntary commitments by each party to reduce greenhouse gas emissions and adapt to climate impacts, with periodic reviews to enhance ambition over time (Article 4, Paris Agreement, 2015). Unlike its predecessor, the Kyoto Protocol, the Paris Agreement adopts a bottom-up approach, allowing countries to set their own targets while fostering transparency and accountability through a global stocktake every five years (Article 14, Paris Agreement, 2015).
The primary goal of limiting global temperature rise to well below 2°C, and ideally to 1.5°C, is grounded in scientific consensus that surpassing these thresholds would result in catastrophic environmental consequences, including sea-level rise, extreme weather events, and biodiversity loss (IPCC, 2018). Furthermore, the agreement emphasizes the need for climate finance, with developed countries pledging to mobilize $100 billion annually by 2020 to support mitigation and adaptation efforts in developing nations (Article 9, Paris Agreement, 2015). Despite these commitments, the global community faces significant hurdles in translating these goals into tangible outcomes.
Challenges in Achieving Global Climate Goals
1. Disparities in National Commitments and Ambition
One of the most significant challenges of the Paris Agreement lies in the voluntary nature of NDCs. While this flexibility was crucial in securing near-universal participation, it has resulted in a wide disparity in ambition and commitment levels. According to the United Nations Environment Programme (UNEP), current NDCs are insufficient to meet the 1.5°C target, with projections suggesting a temperature rise of 2.4–3.5°C by 2100 if policies remain unchanged (UNEP, 2022). Major emitters, such as China and the United States, have made significant pledges—China aiming for carbon neutrality by 2060 and the U.S. rejoining the agreement in 2021 with a target of net-zero emissions by 2050—but implementation lags behind rhetoric. Smaller or developing nations, meanwhile, often lack the resources to meet their targets, highlighting an inequity in capacity that undermines collective progress.
2. Economic and Political Barriers
Economic considerations pose another formidable challenge. Transitioning to a low-carbon economy requires substantial investment in renewable energy, infrastructure, and technology. For many countries, particularly those reliant on fossil fuels, this shift entails economic disruption and resistance from powerful industries. For instance, coal-dependent economies face job losses and energy security concerns, creating political backlash against stringent climate policies (World Bank, 2021). Moreover, political instability or changes in government can derail climate commitments, as seen with the U.S. withdrawal from the Paris Agreement in 2020 under the Trump administration, followed by re-entry under President Biden in 2021, and a subsequent announcement of withdrawal again in 2025 (Wikipedia, 2025).
3. Insufficient Climate Finance
The commitment by developed nations to provide $100 billion annually in climate finance has not been fully realized. As of 2023, reports indicate that funding falls short of this target, with discrepancies in what counts as “climate finance” and a lack of transparency in reporting (OECD, 2023). Developing countries, which are often the most vulnerable to climate impacts, rely on this funding for adaptation and mitigation projects. The shortfall exacerbates global inequalities and hinders the trust necessary for cooperative action, as outlined in Article 9 of the Paris Agreement (2015), which emphasizes the importance of financial assistance and technology transfer.
4. Enforcement and Compliance Issues
The Paris Agreement lacks a robust enforcement mechanism, relying instead on transparency and peer pressure to encourage compliance. While the Enhanced Transparency Framework under Article 13 mandates regular reporting and review of NDCs, there are no legal penalties for non-compliance (Paris Agreement, 2015). This inherent tension between ambition and accountability, as noted in recent analyses, means that countries may prioritize short-term economic or political gains over long-term climate goals (Nature Communications, 2023). Without binding enforcement, the agreement’s effectiveness hinges on the goodwill of its parties, which is often insufficient in the face of competing national interests.
5. Scientific and Technological Gaps
Finally, the pace of technological innovation and deployment remains a barrier. Achieving net-zero emissions requires breakthroughs in carbon capture, renewable energy storage, and sustainable agriculture, among others. While progress has been made, the scale and speed of deployment are inadequate to meet the Paris Agreement’s timelines. Additionally, the IPCC warns that delaying action increases the reliance on unproven technologies, such as geoengineering, which carry significant ethical and environmental risks (IPCC, 2022). These scientific uncertainties compound the challenge of aligning global efforts with the agreement’s temperature goals.
Legal Framework for Entering Treaties: The Case of Country X
To understand how countries engage with the Paris Agreement, it is essential to examine the legal frameworks that govern treaty participation at both international and national levels. Using the hypothetical Country X as a case study, this section explores the processes by which a state can legally enter into treaties like the Paris Agreement under the UNFCCC, the distinction between monist and dualist approaches to treaty incorporation, and the translation of international obligations into national law.
Treaty-Making Power and International Law
Under international law, the ability of a state to enter into treaties is governed by the Vienna Convention on the Law of Treaties (VCLT) of 1969, a foundational document that codifies the rules of treaty formation, interpretation, and termination. Article 6 of the VCLT establishes that every state possesses the capacity to conclude treaties, typically exercised through heads of state, government, or foreign ministers (VCLT, 1969). For Country X, entering the Paris Agreement would involve expressing consent to be bound by the treaty, either through signature followed by ratification, acceptance, approval, or accession, as outlined in Article 11 of the VCLT and Article 20 of the Paris Agreement (2015).
The Paris Agreement, as a treaty under the UNFCCC, specifies in Article 20 that it is open for signature by states that are parties to the UNFCCC, and it enters into force for a state upon depositing an instrument of ratification or accession with the UN Secretary-General, who serves as the depositary (Paris Agreement, 2015). For Country X, assuming it is a party to the UNFCCC, the process would involve formal signature during the designated period (April 22, 2016, to April 21, 2017, at the UN Headquarters) or subsequent accession, followed by ratification through domestic procedures.
Monist vs. Dualist Approaches in Country X
The incorporation of international treaties into national law varies depending on a country’s legal system, which can be classified as monist or dualist. In a monist system, international law is automatically part of domestic law upon ratification, requiring no further legislative action. In contrast, a dualist system treats international and domestic law as separate; treaties must be transposed into national legislation to have legal effect domestically.
For the purposes of this analysis, let us assume Country X adopts a dualist approach, which is common in many common law jurisdictions. In such a system, after the executive branch ratifies the Paris Agreement internationally, the treaty does not automatically become enforceable within Country X. Instead, the legislature must pass domestic laws to implement the treaty’s obligations, such as emissions reduction targets or adaptation policies. This process can be slow and subject to political opposition, particularly if climate policies conflict with economic priorities. For example, Country X’s parliament might need to enact laws establishing a carbon pricing system or renewable energy mandates to align with its NDC under Article 4 of the Paris Agreement (2015). Failure to pass such legislation could result in a gap between international commitments and domestic action, a challenge faced by many dualist states.
In contrast, if Country X were a monist state, the Paris Agreement would directly form part of national law upon ratification, potentially streamlining compliance but raising concerns about sovereignty and the lack of democratic scrutiny over international obligations. Regardless of the system, the effectiveness of treaty implementation in Country X would depend on institutional capacity, judicial enforcement mechanisms, and public support for climate action.
Translation into National Law
In a dualist framework, translating the Paris Agreement into national law in Country X would involve several steps. First, the executive would negotiate and ratify the treaty at the international level. Next, the government would propose legislation to parliament to incorporate the agreement’s provisions, such as setting legally binding emissions targets, establishing regulatory agencies for climate monitoring, or allocating funds for adaptation projects as per Articles 7 and 9 of the Paris Agreement (2015). This legislative process ensures that international commitments are enforceable in domestic courts and aligned with existing legal frameworks. However, delays or amendments during this process could weaken the country’s ability to meet its NDCs, illustrating a key challenge in dualist systems.
Moreover, even in monist systems, supplementary legislation or regulations may be necessary to operationalize broad treaty obligations. For instance, Article 13 of the Paris Agreement requires parties to report on their progress through the Enhanced Transparency Framework (2015). Country X, whether monist or dualist, would need to establish administrative mechanisms to collect and submit emissions data, demonstrating the practical complexities of treaty implementation beyond legal incorporation.
The Paris Agreement and the Vienna Convention on the Law of Treaties (VCLT) 1969
The relationship between the Paris Agreement and the VCLT of 1969 is critical to understanding how countries enter into and interpret their obligations under this treaty. The VCLT, often described as the “treaty on treaties,” provides the legal framework for the formation, application, and termination of international agreements. While the Paris Agreement itself is not a party to the VCLT—since only states can be parties to treaties—the VCLT’s principles apply to the Paris Agreement as customary international law, binding on all states regardless of whether they have ratified the VCLT (ICJ, 1971).
Applicability of VCLT Principles
The Paris Agreement, as a treaty concluded after the entry into force of the VCLT, falls under its purview for states that are parties to the convention. Key provisions of the VCLT, such as those on treaty interpretation (Articles 31–33), reservations (Articles 19–23), and entry into force (Article 24), guide how countries like Country X interact with the Paris Agreement. For instance, under Article 31 of the VCLT, the Paris Agreement must be interpreted in good faith, in accordance with the ordinary meaning of its terms and in the context of its object and purpose—namely, to combat climate change through global cooperation (VCLT, 1969; Paris Agreement, 2015).
Notably, the Paris Agreement allows states to join through ratification or accession without reservations, as per Article 20, aligning with the VCLT’s emphasis on the integrity of treaty commitments (Paris Agreement, 2015). This structure ensures that all parties adhere to the same obligations without modifications, a design choice intended to foster equity but which may deter participation by states seeking flexibility.
Implications for Other Countries
The application of VCLT principles to the Paris Agreement offers valuable lessons for other countries on how to properly enter into treaties under the UNFCCC. First, it underscores the importance of formal consent through signature, ratification, or accession, ensuring that treaty obligations are legally binding under international law (Article 11, VCLT, 1969). Countries must follow their constitutional processes for treaty-making, whether monist or dualist, to avoid discrepancies between international commitments and national capacity to implement them.
Second, the VCLT’s rules on interpretation and compliance can guide countries in navigating disputes or ambiguities within the Paris Agreement. For example, disagreements over the scope of climate finance obligations under Article 9 could be resolved using the VCLT’s interpretive framework, promoting consistency and fairness (Paris Agreement, 2015; VCLT, 1969). Finally, the VCLT’s recognition of customary international law ensures that even non-parties to the convention are bound by its core principles, providing a universal standard for treaty engagement that can encourage hesitant states to join the Paris Agreement without fear of legal inconsistency.
Broader Implications and Recommendations
The challenges facing the Paris Agreement are emblematic of the broader difficulties in achieving global cooperation on climate change. The disparities in national ambition, economic constraints, and lack of enforcement mechanisms highlight the need for innovative solutions to bridge gaps in implementation. Strengthening climate finance mechanisms, enhancing technological transfer, and fostering public-private partnerships are essential steps to support vulnerable nations and accelerate decarbonization efforts globally.
From a legal perspective, the interplay between international treaties like the Paris Agreement and national laws underscores the importance of aligning domestic systems with global commitments. Countries like Country X, whether monist or dualist, must ensure that treaty obligations are not only ratified but also effectively integrated into enforceable national policies. This requires robust institutional frameworks, transparent governance, and public awareness to sustain momentum for climate action.
Furthermore, the guiding role of the VCLT in treaty-making processes offers a blueprint for other countries engaging with the Paris Agreement. By adhering to established international legal norms, states can build trust and legitimacy in their climate commitments, fostering a collective approach to addressing this existential threat. Future amendments or successor agreements to the Paris Agreement should consider incorporating stronger enforcement mechanisms, inspired by other multilateral treaties, to ensure accountability without compromising participation.
Conclusion
The Paris Agreement stands as a pivotal instrument in the global fight against climate change, uniting nations under a shared goal of limiting temperature rise and building resilience to its impacts. However, the challenges in achieving these objectives—ranging from insufficient ambition in NDCs to economic barriers, inadequate financing, and enforcement gaps—reveal the complexities of translating international consensus into actionable outcomes. Legally, the process of entering into treaties like the Paris Agreement, as illustrated through the hypothetical Country X, depends on both international norms under the VCLT and domestic approaches to treaty incorporation, whether monist or dualist. The application of VCLT principles to the Paris Agreement further informs how countries can and should engage with such treaties, ensuring clarity and consistency in their obligations. As the world grapples with the urgent need for climate action, overcoming these challenges will require not only political will and economic innovation but also a commitment to legal frameworks that facilitate meaningful cooperation and accountability.
References
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