The newly developed Multi-ensemble Biomass-burning Emissions Inventory (MBEI): Characterizing and unraveling spatiotemporal uncertainty in global biomass burning emissions

Abstract. Against the backdrop of global climate change, the spatiotemporal patterns of biomass burning are undergoing significant changes. However, large discrepancies among different emission inventories hinder a consensus on the true magnitude and long-term trends of global emissions. This study constructs a framework for estimating biomass burning emissions by integrating bottom-up and top-down approaches with various combinations of multi-source data inputs, resulting in the development of the Multi-ensemble Biomass-burning Emissions Inventory (MBEI). Leveraging this framework, we develop the MBEI global emission dataset covering the period 2003–2023, which comprises eight sub-inventories and provides emission estimates for 11 representative greenhouse gases, aerosols, and atmospheric pollutants, including CO₂, PM_2.5, BC, NO₂, and others. A unique feature of MBEI is its ability to quantify the uncertainty in biomass burning emission estimates across various spatial scales, achieved by calculating the average emissions and their Max-Min band at a 0.1° grid scale from these sub-inventories. The analysis reveals that the global annual CO₂ emissions from biomass burning are approximately 7304 (4400–9657) Tg, with the maximum value being more than double the minimum. Furthermore, the uncertainty in global biomass burning emissions exhibits significant spatial heterogeneity: in low-emission regions such as Australia and the Middle East, the ratio of maximum to minimum emission estimates can reach 6–7 fold, whereas in traditional hotspots like Africa and South America, this ratio is lower, around 1.9 fold. In terms of temporal trends, global emissions showed a decreasing trend from 2003 to 2013, primarily driven by a reduction in burning activities in tropical regions. This trend, however, reversed to an increase from 2013 to 2023, with the primary drivers being intensified burning in northern high-latitude regions and the frequent occurrence of extreme events. Finally, a comparison with existing inventories confirms the reliability of the MBEI dataset. At both global and regional scales, the average of our inventory is centrally positioned among other inventory estimates in most years, offering a more robust central estimate for assessing biomass burning emission intensity during extreme event years. Moreover, its maximum-minimum range encompasses the estimates of other inventories across most regions and time periods. This capability to characterize uncertainty enables the integration of the new datasets MBEI into analytical frameworks, such as atmospheric chemistry models and exposure risk assessments, thereby enhancing the reliability of global biomass burning dynamics analyses and the robustness of the conclusions. The Multi-ensemble Biomass-burning Emissions Inventory (MBEI) dataset is publicly available at https://doi.org/10.5281/zenodo.17128279 (Liu and Yin, 2023).