Abstract The majority of global emissions scenarios compatible with holding global warming to less than 2 °C depend on the large-scale use of bioenergy with carbon capture and storage (BECCS) to compensate for an overshoot of atmospheric CO2 budgets. Recent critiques have highlighted the ethical and environmental risks of this strategy and the danger of building long-term climate policy on such speculative technological scenarios emerging from integrated assessment models. Here, we critically examine both the use of BECCS in mitigation scenarios and the decision making philosophy underlying the use of integrated assessment modelling to inform climate policy. We identify a number of features of integrated assessment models that favour selection of BECCS over alternative strategies. However, we argue that the deeper issue lies in the tendency to view model outputs as objective science, capable of defining “optimal” goals and strategies for which climate policy should strive, rather than as exploratory tools within a broader policy development process. This model-centric decision making philosophy is highly sensitive to uncertainties in model assumptions and future trends, and tends to favour solutions that perform well within the model framework at the expense of a wider mix of strategies and values. Drawing on the principles of Robust Decision Making, we articulate the need for an alternative approach that explicitly embraces uncertainty, multiple values and diversity among stakeholders and viewpoints, and in which modelling exists in an iterative exchange with policy development rather than separate from it. Such an approach would provide more relevant and robust information to near-term policymaking, and enable an inclusive societal dialogue about the appropriate role for carbon dioxide removal within climate policy.

中文翻译：

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深度不确定背景下的决策——长期气候政策的替代方法

摘要 将全球变暖控制在 2 °C 以下的大多数全球排放情景取决于大规模使用生物能源与碳捕获和储存 (BECCS)，以补偿大气 CO2 预算的超调。最近的批评强调了这一战略的伦理和环境风险，以及在综合评估模型中出现的这种推测性技术情景上建立长期气候政策的危险。在这里，我们批判性地研究了 BECCS 在缓解情景中的使用以及使用综合评估模型为气候政策提供信息的决策理念。我们确定了综合评估模型的许多特征，这些特征有利于选择 BECCS 而不是替代策略。然而，我们认为，更深层次的问题在于倾向于将模型输出视为客观科学，能够定义气候政策应努力实现的“最佳”目标和战略，而不是作为更广泛的政策制定过程中的探索性工具。这种以模型为中心的决策理念对模型假设和未来趋势的不确定性高度敏感，并且倾向于支持在模型框架内表现良好的解决方案，而牺牲了更广泛的战略和价值组合。借鉴稳健决策的原则，我们阐明需要一种替代方法，该方法明确包含利益相关者和观点之间的不确定性、多重价值和多样性，并且建模存在于与政策制定的迭代交换中，而不是与政策制定相分离。