Climate change has become one of the most pressing global challenges, posing severe risks not only to ecological systems but also to economic development, international stability, and human well-being (IPCC, 2023). Over the past three decades, the international community has mobilized through a series of multilateral agreements, including the Kyoto Protocol (1997) and the Paris Agreement (2015), to coordinate mitigation and adaptation across national boundaries (UNFCCC, 2022). However, despite growing scientific consensus and repeated diplomatic efforts, aggregate global emissions have continued to rise, and key environmental indicators, such as biodiversity loss, sea level rise, and atmospheric CO₂ concentration, have shown persistent deterioration (DeConto et al., 2021; Chen, 2021).

This persistent gap between international ambition and environmental outcomes has prompted extensive scholarly and policy scrutiny of the structural limitations of contemporary climate governance (Keohane and Victor, 2011; Milkoreit, 2019). Existing treaty frameworks are widely criticized for weak enforcement, reliance on voluntary commitments, and vulnerability to domestic political shifts (Putnam, 2017; Axelrod and Keohane, 1985). At the same time, the geopolitical landscape has shifted toward a multipolar order characterized by power diffusion, regionalism, and competing climate interests among major actors such as the United States, China, and the European Union (Milkoreit, 2019; Snidal, 1985). In such conditions, climate regimes increasingly reflect power asymmetries, national self-interest, and domestic political constraints, often marginalizing weaker states and civil society in agenda-setting and implementation (Hale et al., 2013; Young, 2011; Hafezi et al., 2021). Yet, while the limitations of treaty-based multilateralism are well established, less attention has been given to operational governance alternatives that can function under geopolitical fragmentation rather than assuming sustained consensus.

This paper contributes to this debate by operationalizing a transition-regimes model as a complementary governance architecture to treaty-based multilateralism. Drawing on K-group theory (Snidal, 1985) and two-level game theory (Putnam, 1988), we specify how smaller coalitions of capable actors can generate momentum for mitigation through modular, power-aware arrangements that can function under strategic competition as well as cooperation. Rather than presuming U.S.–China coordination as a baseline, we treat it as one contingent configuration among several, and we outline alternative coalition pathways that can emerge through regional, sectoral, or supply-chain-based leadership. The model further clarifies the role of civil society and non-state actors as legitimacy and compliance amplifiers, and it links burden-sharing to life-cycle emissions accounting as a more politically salient fairness metric.

The paper is structured as follows. We first provide a concise synthesis of well-established explanations for the limited effectiveness of international environmental agreements, focusing on enforcement deficits, distributional conflict, and representation gaps. We then develop the transition-regimes model in detail by (i) defining its institutional logic and scope, (ii) specifying actor configurations beyond a single great-power core, (iii) outlining key mechanisms and policy instruments through which such regimes can operate, and (iv) clarifying how legitimacy can be generated through bottom-up pressures without assuming global consensus. The final section discusses feasibility conditions, trade-offs, and implications for future climate diplomacy under geopolitical fragmentation.

Climate change and environmental concerns pose significant challenges to sustainable development at both global and national levels (Hafezi and Alipour, 2020). As human activities continue to impact the planet’s ecosystems and climate, there is an urgent need for collective action to mitigate these effects. The perspective presented seeks to address the central research questions: Are international environmental agreements effective in achieving their goals? and, do economic interests ultimately undermine their success? Some answers and solutions are proposed to tackle the global challenges related to climate change, which endangers the survival of mankind and a large portion of the life that currently exists on Earth in the long run. This work offers perspective addressing a real conundrum, analogous to that of the frog placed in gradually heated water (referring to the tale of the boiling frog). It is crucial to make decisions and take actions, otherwise, we will rightly be held accountable by future generations (i.e., history) for the damage knowingly caused to our planet. Sitting on the fence or procrastinating cannot be justified any longer, difficult decisions leading to positive climate impacts need to be taken, and in fact are now long overdue. We cannot steal other generations’ futures and leave a permanently damaged environment as our legacies.

International environmental agreements have evolved through successive rounds of multilateral negotiation aimed at coordinating collective responses to transboundary environmental risks. Despite broad participation and repeated political commitments, these arrangements have consistently struggled to translate ambition into durable emissions reductions. Their design has remained heavily reliant on voluntary pledges, weak enforcement, and short political time horizons, making them vulnerable to shifts in domestic priorities and economic pressures. As a result, climate diplomacy has increasingly taken the form of symbolic coordination rather than structurally transformative governance.

The limited effectiveness of international accords is further illustrated by the fact that the most significant short-term reductions in emissions over recent decades occurred not through negotiated climate policy, but as unintended consequences of economic disruption, such as the 2009 financial crisis and the COVID-19 lockdowns. This underscores the extent to which emissions trajectories remain structurally coupled to economic activity rather than governed by treaty commitments.

Another drawback of multinational accords is their fragility and lack of long-term binding commitments, allowing countries to withdraw from them (e.g., the United States’ exit from the Paris Agreement) or dilute their commitments based on national interests promoting economic growth. Economic growth typically necessitates increased energy consumption, and as the energy mix for the most populous nations is still dominated by fossil fuels, this inevitably leads to greater atmospheric pollution (Hafezi et al., 2021). Consequently, the altruistic objectives of preserving favorable conditions on Earth for ecosystems to thrive are undermined by national economic growth drivers. At the level of international environmental agreements, it is clear that “money talks,” especially for some nations, and, unfortunately, at the expense of others. Thus, a dichotomy exists between environmental aspirations and economic growth objectives in many countries. At this point, the central challenge is no longer whether treaty-based climate regimes suffer from structural limitations, as this is well established, but whether alternative governance architectures can operate effectively under conditions of geopolitical competition, economic asymmetry, and limited trust. Addressing this question requires moving beyond critique toward the design of transition regimes that are capable of mobilizing action without presuming consensus.

A central challenge in international climate negotiations arises from persistent conflicts of interest among developed, developing, and less developed economies. While game-theoretic approaches suggest that durable cooperation requires mutually beneficial outcomes, such models often abstract from power asymmetries, divergent development trajectories, and unequal exposure to climate risks. In practice, climate negotiations unfold among actors with highly uneven bargaining power and time horizons, making universal, symmetric commitments politically unstable.

It is instructive to examine the sources of historical cumulative CO₂ emissions from countries responsible for the largest emissions reported from 1850 to 2021 (Figure 1). Two main contributions can be identified: (1) CO₂ emissions related to fossil fuel consumption (grey bars); and (2) CO₂ emissions related to land-use change and deforestation (green bars). From 1950, fossil fuel-related CO₂ emissions increased about 3.85 times, from 6.5 Gt in 1950 to 25.1 Gt in 2000. In contrast, land-use-change-related CO₂ emissions experienced about a 22% decrease from about 5.5 Gt in 1950 to 4.3 Gt in 2000. These statistics underscore the significance of fossil fuels and increased energy demand for economic and population growth in their contributions to CO₂ emissions growth. However, such aggregate national accounting obscures the political nature of responsibility attribution, as it embeds implicit assumptions about production, consumption, and benefit-sharing that are themselves contested.

National contributions to CO₂ emissions are not as clear-cut as the Figure 1 statistics suggest. A more relevant approach involves analyzing national contributions to emissions in a more holistic manner. One such method is to incorporate a life-cycle analysis related to the production and consumption of key commodities and services. This would involve considering the extraction of raw materials at one end of the life cycle along various supply chains, through processing, manufacturing, and distribution, to post-consumption recycling of waste materials (termination of life cycle). Thus, emissions recorded by resource-rich nations (through extraction and distribution processes) should not be attributed solely to the producing nations but also partially shared with those nations consuming, transporting and trading the commodities and services. Recording net or life-cycle contributions to CO₂ emissions would provide a more accurate recognition of the nation’s most responsible for such emissions.

A less explored but structurally important issue concerns the allocation of emissions associated with early-stage technology development. Innovation processes undertaken primarily in industrialized economies have historically generated significant emissions, while simultaneously producing technologies and knowledge that diffuse globally and reduce marginal emissions elsewhere. This creates a governance dilemma: attributing such emissions exclusively to early industrializers overstates national responsibility, while simple per capita allocation fails to capture unequal access to technological benefits. For countries still striving to industrialize, assigning the costs of historical innovation-related emissions risks entrenching developmental asymmetries. From a governance perspective, this reinforces the limitations of territorially bounded accounting and supports the case for life-cycle-based metrics that can distribute responsibility in a manner compatible with differentiated development trajectories.

Concerns regarding sovereignty, enforcement, and strategic manipulation are well founded and have long constrained the effectiveness of universal climate agreements. These constraints do not undermine the case for alternative governance architectures; rather, they define the conditions under which such alternatives must operate. Transition regimes explicitly accommodate partial participation, differentiated obligations, and non-coercive enforcement mechanisms, relying on incentives, conditional access, and reputational effects rather than formal legal compulsion. From a governance perspective, life-cycle-based metrics are not merely fairness adjustments; they enable modular burden-sharing arrangements that are better suited to transition regimes operating without universal agreement.

Another factor concerns how the economically developed world should support developing and underdeveloped nations to help them achieve targeted economic growth and improve their living standards. This includes facilitating access to sufficient, relatively low-cost, clean energy sources. In the current world, many nations, particularly developing ones, opt for the cheapest or most accessible energy solutions. Unfortunately, many of these solutions are the least environmentally friendly (e.g., coal without carbon capture). The position taken, and the modifications demanded to the final COP26 statement by India exemplify how conflicts of interest can lead to lobbying, attenuation, refusal, and even withdrawal from international environmental commitments.

Such conflicts of interest primarily arise from the economic drivers influencing national policy decisions. This suggests that economic solutions, such as CO₂ emission taxes, are required. The fairest way to implement such a fiscal solution would be to use net (life-cycle) emissions, with the proceeds of the taxes raised allocated to provide financial and technical assistance to less developed nations, thereby helping them meet environmental commitments while combating poverty by ensuring a certain level of economic growth. To implement such a fiscal system, fair and unbiased international regulators with enforcement powers would be necessary. Moreover, this system would need to be accountable and demonstrate tangible emissions reduction benefits. Such systems are, of course, of no use if they just work on paper and/or are subject to manipulation by vested interests.

In sum, conflicts of interest in climate governance are not anomalies to be resolved through better negotiation alone; they are structural features of a fragmented global political economy. Any viable response must therefore move beyond uniform treaty obligations toward governance models that can operate through differentiated responsibilities, flexible coalitions, and politically salient metrics of contribution. These conditions form the analytical foundation for the transition-regimes model developed in the following sections.

Political systems and their relationship with sustainability have faced criticism due to the complex nature of balancing various interests and the long-term consequences of policy decisions. Major challenges related to sustainability and political systems include addressing the negative impacts of climate change, fostering sustainable development, and managing the trade-offs between short-term gains and long-term environmental and social goals. In his book titled “Sustainability,” Portney investigates the concept of sustainability, focusing on urban sustainability programs, and analyzes a range of case studies through qualitative and quantitative methodologies (Portney, 2015).

To tackle unsustainability social movement is crucial which is represented in a political context as democracy. Interestingly, Chapman et al. (2023) showed that civil interpretation of social complexity and understanding of democracy complexity significantly affect how they demand and support democracy. So experiencing democracy in the real world increases the possibility of demanding democracy and governmental responsibility (e.g., transparency) (Huang et al., 2013). Although regime type influences democracy and demand for it at the individual level, it has been proved that individual activities and support for democracy are important predictors of the democratization of society regardless of regime type (Chapman et al., 2023).

Cities represent the largest part of society where climate change clearly displays its negative consequences. For instance, climate change-induced extreme weather events and sea-level rise is likely to result in mass migrations from many low-lying coastal cities (although in most cases such Hurricane Katrina migrations were just temporary, still uncertainties are existing). Additionally, increased healthcare costs can be attributed to urban air pollution, which exacerbates respiratory and cardiovascular diseases (Anenberg et al., 2018). Young (2011) highlights concerns about sustainability motivating actions based on limiting or reducing consumption, defining consumption and waste reduction as the ultimate solutions to improve sustainability. However, resistance has emerged in response to these measures.

The first source of resistance is initiated and supported by developing and less developed economies that are on the path to improving their quality of life. Global treaties, such as the Paris Agreement, force these nations to slow down development, at least in its current form, which are likely to create some tensions between the goals of economic growth and environmental sustainability.

The second source of resistance is rooted in the economy. Sustainable development requires the full participation of economic parties, as economic directions affect human well-being in the long run. From a politician’s perspective, there is a trade-off between choosing to follow optimal future-oriented decisions (e.g., CO₂ taxes) and satisfying short-term social and economic needs, which are more likely to result in future re-election. This dilemma is exemplified by the U.S. withdrawal from the Paris Agreement in 2017, prioritizing economic interests over global climate goals (Keohane and Victor, 2011).

While the solution may appear simple, the path toward sustainability is difficult due to the need to consider multiple agents with various interests and even significant conflicts. To address these challenges, policymakers must engage in open dialogue with stakeholders, develop flexible strategies to balance economic growth and environmental concerns and transparently prioritize long-term sustainability in decision-making processes.

Expectations that the post–Cold War international order would converge toward liberal cooperation have proven overly optimistic. Over the past two decades, democratic backsliding, rising authoritarianism, and strategic competition have reshaped the conditions under which global cooperation occurs (Diamond, 2008). Climate governance now unfolds within a fragmented political landscape characterized by asymmetric power, divergent development priorities, and declining trust. These conditions fundamentally constrain the design space of any effective climate governance architecture.

Under conditions of geopolitical fragmentation, transition regimes are most likely to emerge through coalitions of actors with sufficient economic, technological, and regulatory capacity to shape incentives beyond their borders. While cooperation among dominant powers can significantly enhance regime effectiveness, it should be treated as a facilitating rather than a necessary condition. Transition regimes may also arise through partial, issue-specific, or regionally anchored coalitions that operate without comprehensive great-power alignment.

Snidal proposed the K-group theory, where K demonstrates the number of dominant nations that support a specific regime (Snidal, 1985). The optimum number for such group theory is one (e.g., K = 1), however, as long as that one nation can manage collective actions, regardless of the other states in the group. The K-group theory discusses why the U.S. and China have become less willing to cooperate since 2015 (Milkoreit, 2019). It seems likely that annual global greenhouse gas emissions have not yet peaked. For example, global atmospheric CO₂ concentrations and sea level continue to rise (DeConto et al., 2021; Chen, 2021). As time goes by without those emissions being abated the greater the environmental consequences will be for the planet. Hence, the need to initiate transition regimes to adapt to and effectively mitigate the key impacts of climate change requires urgent consideration.

K-group theory offers a useful lens for understanding how small coalitions can initiate collective action under conditions of asymmetric power. However, in the context of climate governance, K-groups should be conceptualized as flexible configurations rather than fixed hegemonic cores. At least three configurations are analytically plausible: (i) a cooperative core configuration, in which major emitters coordinate on limited but high-impact measures; (ii) competitive miniliteralism, where multiple coalitions pursue overlapping mitigation pathways under strategic rivalry; and (iii) regional or sector-specific K-groups, organized around supply chains, technologies, or regulatory standards. These configurations are not mutually exclusive and may evolve over time. Each configuration involves trade-offs between speed, inclusiveness, and durability, underscoring that transition regimes prioritize functional effectiveness over formal universality.