Achieving net-zero emissions by 2050 will require tackling both energy-related and non-energy-related GHG emissions, which can be achieved through the transition to a circular economy (CE). The focus of climate change crisis reversal has been on the energy-related continuum over the years through promoting renewable energy uptake and efficiency in energy use. Clean energy transition and efficiency gains in energy use alone will not be sufficient to achieve net-zero emissions in 2050 without paying attention to non-energy-related CO₂ emissions. This study systematically reviews the CE literature across different themes, sectors, approaches, and tools to identify accelerators in transitioning to a CE. The study aims to understand and explore how technology, finance, ecosystem, and behavioral studies in the CE paradigm can be integrated as a decision-making tool for CE transition. The material analysis was carried out by identifying the main characteristics of the literature on CE implementation in the agriculture, industry, energy, water, and tourism sectors. Results of the literature survey are synthesized to engender clarity in the literature and identify research gaps to inform future research. Findings show that many studies focused on technology as an accelerator for CE transition, and more studies are needed regarding the CE ecosystem, financing, and behavioral aspects. Also, results show that CE principles are applied at the micro-, meso-, and macro- (national, regional, and global) levels across sectors with the dominance of the industrial sector. The agriculture, water, and energy sectors are at the initial stages of implementation. Additionally, the use of carbon capture and utilization or storage, conceptualized as a circular carbon economy, needs attention in tackling CE implementation in the energy sector, especially in hydrocarbon-endowed economies. The major implication of these findings is that for CE to contribute to accelerated net-zero emission by 2050, coordinated policies should be promoted to influence the amount of financing available to innovative circular businesses and technologies within an ecosystem that engenders behavioral change towards circularity.

Implementing a carbon pricing policy in any country remains a complex challenge, requiring the careful navigation of economic, social, and political factors to ensure policy coherence and stakeholder buy-in. Given the critical role of carbon pricing in achieving net-zero emissions by 2050, this study provides empirical evidence on the impact of carbon price implementation on carbon emission reductions globally. The study is motivated by the a priori assumption that carbon pricing policies incentivize polluters to adopt carbon-neutral technologies, leading to emission reductions. Using data from 30 jurisdictions between 1990 and 2020, comprising both developed economies and eight emerging markets where either a carbon tax, an emission trading system, or both have been implemented, we assess the effectiveness of carbon pricing mechanisms while controlling for economic growth, population, energy intensity, and environmental policy stringency. The findings confirm that carbon pricing leads to a significant reduction in emissions, with the Emission Trading System proving to be more effective in accelerating emission reductions than the carbon tax. Specifically, the Emission Trading System is associated with a 12.06% reduction in carbon emissions, compared to an 8.91% reduction under the carbon tax. These results underscore the importance of market-based mechanisms in driving decarbonization efforts. The findings also have critical policy implications, highlighting the need for tailored carbon pricing strategies that align with national economic structures and political contexts. Robustness checks and policy recommendations are provided to guide policymakers in designing effective carbon pricing frameworks to enhance climate mitigation efforts.