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A comprehensive assessment of European forest-based biomass harvest potentials, their future utilization and implications on international wood product markets and forest carbon dynamics requires the capability to model forest resource development as well as global markets for wood-based commodities with sufficient geographical and product detail and, most importantly, their interactions. To this aim, we apply a model framework fully integrating a European forest resource model and a global economic forest sector model. In a business-as-usual (BaU) scenario, European Union harvests increase seven percent by 2030 compared to past levels (485 million m3 on 2000-2012 average and 517 million m3 in 2030). The subsequent annual carbon stock change is a ten percent reduction by 2030 compared to 2000-2012 average (equal to 119.3 Tg C yr-1), corresponding to decreasing carbon-dioxide removal by the European forests. A second, high mobilization scenario (HM), characterized by the full utilization of the potential wood supply and a doubling of EU wood pellets consumption, was designed to explore potential impacts on forest carbon dynamics and international wood product markets under intensive exploitation of biomass resources. In the HM scenario, harvest increases by 55% (754 million m3 in 2030) compared to the BaU scenario. Fuelwood accounts for this increase in harvest levels as overall competition effects from increased wood pellets consumption outweighs synergies for material uses of wood, resulting in slightly reduced harvests of industrial roundwood. As expected, this increasing harvest level would significantly impair carbon-dioxide forest sequestration from the atmosphere in the medium term (-83% in 2030, compared to 2000-2012 average).

International audience; Robust estimates of CO2 budget, CO2 exchanged between the atmosphere and terrestrial biosphere, are necessary to better understand the role of the terrestrial biosphere in mitigating anthropogenic CO2 emissions. Over the past decade, this field of research has advanced through understanding of the differences and similarities of two fundamentally different approaches: “top-down” atmospheric inversions and “bottom-up” biosphere models. Since the first studies were undertaken, these approaches have shown an increasing level of agreement, but disagreements in some regions still persist, in part because they do not estimate the same quantity of atmosphere–biosphere CO2 exchange. Here, we conducted a thorough comparison of CO2 budgets at multiple scales and from multiple methods to assess the current state of the science in estimating CO2 budgets. Our set of atmospheric inversions and biosphere models, which were adjusted for a consistent flux definition, showed a high level of agreement for global and hemispheric CO2 budgets in the 2000s. Regionally, improved agreement in CO2 budgets was notable for North America and Southeast Asia. However, large gaps between the two methods remained in East Asia and South America. In other regions, Europe, boreal Asia, Africa, South Asia, and Oceania, it was difficult to determine whether those regions act as a net sink or source because of the large spread in estimates from atmospheric inversions. These results highlight two research directions to improve the robustness of CO2 budgets: (a) to increase representation of processes in biosphere models that could contribute to fill the budget gaps, such as forest regrowth and forest degradation; and (b) to reduce sink–source compensation between regions (dipoles) in atmospheric inversion so that their estimates become more comparable. Advancements on both research areas will increase the level of agreement between the top-down and bottom-up approaches and yield more robust knowledge of regional CO2 budgets.