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RMI conducted pilots with BCG, Roland Berger, and Estuaire to compare contrail accounting methods. The results show that a bottom-up, flight-specific approach is significantly more accurate than the standard 1.7x multiplier, revealing that 2% of flights cause 80% of contrail impacts. The report advocates for a phased transition toward high-fidelity accounting to enable targeted corporate travel policies and alignment with emerging EU regulations.

The briefing distinguishes between attributional accounting, which allocates emissions responsibility, and consequential assessment, which estimates how specific corporate actions change total greenhouse gas emissions. It argues that while attributional reporting is necessary for inventories, it fails to quantify real-world abatement or value actions like grid storage. By adopting modernized consequential methods, companies can prioritize interventions—such as siting solar projects in coal-heavy regions—that drive faster grid decarbonization.

The document outlines how different international organizations estimate fossil-fuel subsidies, highlighting the distinction between the 'Inventory Approach' used by the OECD and GSI and the 'Price-Gap Approach' used by the IEA and IMF. It notes that estimates vary based on the types of support included, the countries and fuels covered, and the time periods analyzed. While most focus on direct fiscal incentives, the IMF's 'post-tax' measure uniquely includes implicit support from the failure to charge for environmental damages and externalities.

The study found that the closed static chamber (CSC) approach typically underestimates soil CO2 fluxes compared to the closed dynamic chamber (CDC) system when using long sampling periods, but provides comparable results when sampling is limited to the initial 15 minutes.