This paper concludes the collection on an extended scenario exercise that examined governance challenges and potential responses for solar geoengineering. It synthesizes the experiences of eight participant groups who worked with four scenarios of unauthorized use of solar geoengineering. It draws both substantive insights about solar geoengineering risks and governance and methodological insights for the use of scenario exercises to explore this issue, as well as identifying major uncertainties and questions raised by the exercise. Prominent themes include the need for strategic sequencing of actions by those initiating and responding to solar geoengineering challenges; the nature and foundations of potential opposition; the widespread interest in normalizing or domesticating a disruptive intervention after the fact; the importance of embedding solar geoengineering actions in the broader context of climate policy and the difficulty of doing so given their disruptive character; and the importance and likely structure of negotiations to move from initial disruptive action, whatever its initiators and form, to expand participation and embed solar geoengineering decisions in a broadly legitimate multilateral governance structure. In the closing section, we propose directions for further scenario-based explorations of solar geoengineering and its governance challenges.

本文总结了一个扩展场景练习的集合，该练习检查了太阳能地球工程的治理挑战和潜在响应。它综合了八个参与小组的经验，他们处理了四种未经授权使用太阳能地球工程的场景。它汲取了关于太阳能地球工程风险和治理的实质性见解，以及使用情景演练探索这个问题的方法论见解，以及确定演练中提出的主要不确定性和问题。突出的主题包括那些发起和应对太阳能地球工程挑战的人需要对行动进行战略排序；潜在反对的性质和基础；对事后破坏性干预正常化或驯化的广泛兴趣；将太阳能地球工程行动纳入更广泛的气候政策背景的重要性以及鉴于其破坏性特征而这样做的难度；以及谈判的重要性和可能的​​结构，从最初的破坏性行动（无论其发起者和形式如何）转变为扩大参与并将太阳能地球工程决策嵌入广泛合法的多边治理结构中。在结尾部分，我们提出了进一步基于场景的太阳能地球工程及其治理挑战的探索方向。扩大参与并将太阳能地球工程决策嵌入广泛合法的多边治理结构中。在结尾部分，我们提出了进一步基于场景的太阳能地球工程及其治理挑战的探索方向。扩大参与并将太阳能地球工程决策嵌入广泛合法的多边治理结构中。在结尾部分，我们提出了进一步基于场景的太阳能地球工程及其治理挑战的探索方向。