By moving goods and people over large distances, air transport facilitates international trade and tourism and thus contributes to economic growth and job creation. At the same time, it also comes with environmental challenges, largely related to air emissions and their impact on global warming. Air transport has been disproportionately negatively affected by the COVID-19 pandemic with associated reductions in air emissions. However, recent projections show that, in the absence of accelerated technological developments and more ambitious policy measures, aviation-related carbon dioxide (CO2) emissions will grow again at a rapid pace after the pandemic. This paper describes a new OECD database providing near-real-time and global information on aviation-related CO2 emissions, with allocations across countries following either the territory or the residence principle. This database provides a public good for both statistical measurement and environmental policy analysis. On the statistical front, it will facilitate the compilation of global Air Emission Accounts according to the System of Environmental Economic Accounting (SEEA), bring granular and timely information on a significant source of CO2 emissions, and allow tracking their evolution during and after the COVID-19 pandemic. The comparison with official statistics that are available with a significant delay and at lower frequency demonstrates the accuracy of the OECD estimates. On the environmental policy front, it is expected that the OECD database will help monitor the impact of technological developments and policy measures to curb aviation-related CO2 emissions in the future.