CO2 Emissions in Air Transport: A Comparative Study Using Data Envelopment Analysis

The international community has been actively addressing the issue of reducing carbon dioxide (CO2) emissions, as evidenced by various initiatives such as Rio 92, Rio +20, the Paris Agreement, and the 2030 Agenda. These endeavors aim to promote sustainability worldwide. While air transport accounts for only 2% of anthropogenic CO2 emissions, its projected growth has spurred the exploration of new technologies to enhance aircraft efficiency. Consequently, further studies are necessary to assess the efficiency and impact of air transport on CO2 emissions in most countries. A methodology utilizing data envelopment analysis (DEA) is proposed in this study for this purpose. This methodology correlates the structure and annual air movement of 21 countries with CO2 production, considering it an undesirable output. The clustering method establishes the relationship between DEA efficiency, the number of airports, air traffic movements (landings and take-offs), and annual economic factors such as gross domestic product in these countries. Additionally, a regression analysis is conducted to examine the influence of air transport on CO2 emissions from transport systems. The findings reveal that the U.S. and China exhibit low efficiency as outliers because of their significant economic disparities. Other countries are grouped based on economic similarities, with South American nations such as Colombia and Chile showing lower air traffic movement efficiency compared with economically powerful European countries such as the UK and Germany. However, the impact of air transportation variables on CO2 emissions remains substantial.