Earth observation for land representation: implementing the Paris Agreement requirements for greenhouse gas reporting

Under the Paris Agreement, Parties committed to curbing greenhouse gas (GHG) emissions to limit global warming. The Enhanced Transparency Framework (ETF) has introduced new reporting standards for all Parties, including Biennial Transparency Reports (BTRs), starting in December 2024. These reports require the submission of national GHG inventories (NGHGIs) following the Intergovernmental Panel on Climate Change (IPCC) guidelines. Reporting in the Land Use, Land-Use Change and Forestry (LULUCF) sector is challenging due to complex land dynamics and data requirements. Earth Observation (EO) has emerged as a crucial tool to improve the accessibility, accuracy, and consistency of land representation in NGHGIs. Yet, its current use in official submissions has not been systematically evaluated. The first BTRs provide a timely opportunity to analyse the global status of EO integration by all Parties. This study presents the first global assessment of EO’s application in LULUCF reporting submissions, including the first BTRs, by cataloguing countries that use EO for land representation, assessing the types of EO data, products, and tools currently employed in LULUCF reporting, and analysing their adherence to IPCC-compliant requirements. Despite progress in EO, LULUCF reporting remains heterogeneous, with only 75 of 195 Parties explicitly reporting the use of EO. Global EO products (i.e. datasets derived from satellite remote sensing, such as land cover maps) are particularly underused, featuring in only 14% of the assessed submissions. The results highlight the inadequacy and poor usability of existing products, emphasizing the need for global solutions and harmonized, scalable methodological frameworks. The study identifies key gaps in current EO-based reporting methodologies and discusses opportunities to improve reporting, focusing on compliance with ETF and IPCC requirements. Greater collaboration between EO communities and inventory compilers is recommended to align targets, improve the compliance of EO datasets, and contribute to the achievement of the Paris Agreement’s mitigation goals.