Green trade, governance, finance, and energy efficiency: Shaping environmental landscape in global powerhouses

As global environmental concerns intensify, identifying the key drivers of CO₂ emissions (CO₂e) becomes vital, particularly for high-energy-consuming nations. The present study delves into the impacts of green trade (GT), energy efficiency (EF), research and development (R&D), economic growth (EG), financial expansion (FE), and population density (PD) on CO₂e across the top 20 energy-consuming countries from 2000 to 2022. We introduce three key innovations: (i) a novel environmental governance index (EGI), constructed using a distance-based and time-sensitive method, capturing governance progress under best- and worst-case trajectories; (ii) GT as a direct mitigation pathway, shifting the focus from aid-driven environmental finance to market-linked, credit-based green investment; and (iii) a refined approach to EF, highlighting reductions in carbon intensity per unit of economic output. Using the cross-sectionally augmented autoregressive distributed lags model, our findings highlight that GT and EF consistently mitigate CO₂e in both the short and long run, while EG positively impacts CO₂e. R&D and EGI effectively curb CO₂e only in the long run, whereas FE and PD increase emissions. Notably, EGI moderates these relationships-dampening the adverse effects of EG, FE, and PD, while amplifying the mitigating impact of GT, EF, and R&D. These results are further validated through the common correlated effects mean group and augmented mean group methodologies, reinforcing the consistent influence of these factors on CO₂e. The findings offer targeted, institution-sensitive policy recommendations for achieving environmental sustainability.