Analyzing the Economic Factors Affecting Carbon Dioxide Emissions Using a Meta-Analysis Approach

In recent decades, the increasing degradation of the environment has prompted policymakers to adopt measures aimed at reducing environmental damage. Accordingly, the present study aims to evaluate the economic factors affecting carbon dioxide emissions—one of the most important indicators of environmental quality—in developing countries through a comprehensive review of studies published between 2000 and 2023 using a meta-analysis approach. The initial selection criteria for studies included the presence of relevant keywords in the title or abstract and the completeness of the study. After excluding irrelevant studies, 46 articles remained for the final review. The findings indicate that the most influential factors affecting CO2 emissions in the examined studies are gross domestic product (GDP), energy consumption, international trade, urbanization rate, population growth, financial development, and industrialization. Among these, GDP and energy consumption were the most frequently studied variables. Furthermore, all mean effect sizes were greater than 0.2 and less than 0.5, indicating that these factors have a moderate effect. The Environmental Kuznets Curve (EKC) hypothesis and the Pollution Haven Hypothesis (PHH) are both supported, with most studies finding that energy consumption, urbanization, and population growth have a positive effect on CO2 emissions. In contrast, financial development has an adverse impact. Based on these results, policies such as optimal energy pricing, reforming international trade regulations, improving the quality of life in rural areas, promoting financial development, and implementing environmental taxes on polluting industries could help reduce CO2 emissions.