Model‐based global projections of future land‐use and land‐cover (LULC) change are frequently used in environmental assessments to study the impact of LULC change on environmental services and to provide decision support for policy. These projections are characterized by a high uncertainty in terms of quantity and allocation of projected changes, which can severely impact the results of environmental assessments. In this study, we identify hotspots of uncertainty, based on 43 simulations from 11 global‐scale LULC change models representing a wide range of assumptions of future biophysical and socioeconomic conditions. We attribute components of uncertainty to input data, model structure, scenario storyline and a residual term, based on a regression analysis and analysis of variance. From this diverse set of models and scenarios, we find that the uncertainty varies, depending on the region and the LULC type under consideration. Hotspots of uncertainty appear mainly at the edges of globally important biomes (e.g., boreal and tropical forests). Our results indicate that an important source of uncertainty in forest and pasture areas originates from different input data applied in the models. Cropland, in contrast, is more consistent among the starting conditions, while variation in the projections gradually increases over time due to diverse scenario assumptions and different modeling approaches. Comparisons at the grid cell level indicate that disagreement is mainly related to LULC type definitions and the individual model allocation schemes. We conclude that improving the quality and consistency of observational data utilized in the modeling process and improving the allocation mechanisms of LULC change models remain important challenges. Current LULC representation in environmental assessments might miss the uncertainty arising from the diversity of LULC change modeling approaches, and many studies ignore the uncertainty in LULC projections in assessments of LULC change impacts on climate, water resources or biodiversity.

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Bioenergy is an important renewable energy carrier with uncertainties in future development due to sustainability issues. Its further development requires a robust bioenergy strategy on a national level. To provide these strategy elements, a dedicated approach was developed, which includes a new modeling framework, an impact assessment, and stakeholder involvement. Demonstrating the approach on the example of Germany, four bioenergy utilization scenarios for a period up to 2050 have been assessed using seven indicators that cover aspects from local infrastructure to global food security. The devised strategy elements address the national and international feedstock supply, promising fields of utilization, and appropriate frame conditions. The results coherently focus on a wide range of policy fields, which has not been possible in the past. IntroductionBioenergy is made from renewable biomass sources. In recent decades, it has been the most significant renewable energy carrier in Germany, Europe, and the world [1][2][3]. On a global level, bioenergy counts today for 100 % of the renewable transport fuels, over 90 % of modern renewable heat, and 8 % of renewable power [3], with a significant rise in bioenergy utilization through all sectors, which means a doubling of the use between 2006 and 2014, and significantly contribute to global greenhouse gas (GHG) emission reduction [4]. Advanced renewable energy goals and the availability of a wider spectrum of costefficient renewable energy technologies, i.e., wind power, photovoltaics, heat pumps, and e-mobility, mean the role of bioenergy in future energy systems is expected to change [5][6][7]. However, concerns have also arisen about the availability of feedstock to cover additional energy demands using bio-based energy carriers. Although biomass is a renewable resource, its availability is limited at a certain point in time, especially when environmental impacts on biodiversity, soil quality, natural carbon stocks and sinks, e.g., are taken into account [8][9][10]. Nevertheless, the rise in the demand for biomass for food production, feed production, and material use is expected to continue in the future [11][12][13][14]. It is commonly agreed that bioenergy has to be utilized in line with the goals of sustainable development; in particular, food security ranks higher than using biomass for energetic purposes [15,16].

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