Navigating the Fog: An Evaluation of European Airline GHG Emissions Reporting

Luis Martín-Domingo^{1, 2}; Marina Efthymiou ¹; and Miguel Mújica-Mota³

¹ Dublin City University; ² Ozyegin University; ³ Amsterdam University of Applied Sciences

Abstract

The Aviation Zero Emission by 2050 (AZERO2050) study systematically evaluates the greenhouse gas (GHG) emissions reporting practices of European airline groups, focusing on both mandatory and voluntary key performance indicators (KPIs) as shaped by evolving regulatory frameworks and the long-term ambition to reach net zero by 2050. By analysing annual and sustainability reports from 16 major airline groups, the research identifies significant progress in the disclosure of core metrics such as Total CO₂ Scope 1 emissions and Emissions Intensity, reflecting growing regulatory alignment and stakeholder expectations. However, the findings also reveal persistent gaps and inconsistencies, particularly in the reporting of Scope 2 and 3 GHG emissions, energy consumption, GHG removals, and emerging metrics related to Sustainable Aviation Fuel (SAF) and non-CO₂ effects—areas critical for tracking progress towards AZERO 2050. The proliferation of voluntary KPIs further complicates comparability due to a lack of standardization and clear definitions. These challenges are compounded by risks of greenwashing, where airlines selectively report favourable data, and greenhushing, where substantive achievements are under-communicated. The study concludes that while regulatory frameworks such as the CSRD, EU ETS, CORSIA, and ReFuelEU are driving improvements, further harmonization and methodological clarity are required to ensure transparency, comparability, and genuine progress toward aviation climate goals.

Keywords: Sustainable Aviation, Airline Emissions Reporting, Sustainability KPIs, Greenwashing, climate change.

Related paper:

Martín-Domingo, L., Efthymiou, M., & Mujica Mota, M. (2025). Airline sustainability reporting in Europe: Progress, compliance and challenges. Environmental and Sustainability Indicators, 28, 101008. https://doi.org/10.1016/j.indic.2025.101008