A Moderate-Resolution, Long-Term Global Radar-Based Forest Above-Ground Biomass Dataset from 1993 to 2020

Abstract. Understanding global carbon dynamics and budgets under climate change, land-use shifts, and increasing disturbances remains challenging due to the limitations of existing coarse spatial resolution and short-term or discontinuous biomass datasets. In this study, we generated a new global annual forest above-ground biomass dataset at 8.9 km spatial resolution from 1993 to 2020. This dataset is derived from satellite radar backscatter data and integrates background climate constraints to accounts for regional differences and improve the accuracy of global above-ground biomass mapping. Our dataset estimates an average global forest above-ground biomass carbon stock of 191 ± 2.5 PgC, aligning with other global estimates. We observed an increase in global forest above-ground biomass carbon stocks from 1993 to 2020 at a rate of 0.29 PgC yr⁻¹. Tropical Africa, temperate and boreal forests are the primary contributors to global forest above-ground biomass carbon stock gains from 1993 to 2020. In contrast, gross above-ground biomass carbon losses are predominantly observed in tropical America and Asia forests, particularly since 2000. This long-term, temporally continuous, and moderate-resolution dataset provides a new benchmark for quantifying biomass carbon dynamics and integrating these processes into Earth System Models. The above-ground forest biomass dataset is openly accessible, alongside this manuscript.