Comparative assessment of potential impacts, side-effects and uncertainties of CE measures and emission-reduction efforts (ComparCE-2)

ComparCE项目的主要目标是综合评估各种气候工程（CE）措施和减排努力，同时考虑到评估所依据的地球系统模式模拟的不确定性。我们希望解决各种紧迫的问题，我们认为目前为止在CE评估的背景下遗漏了这些问题。作为第一步和中心步骤，将调查哪些评估指标和指标在环境行政方面是重要的，从而对整个优先方案是重要的，以及它们与气候变化评估指标有何不同。在气候变化这一领域已经有了研究，但对于欧盟委员会的辩论来说，这一评估是缺失的。从与国际CE研究小组的交流中，很明显，未来的CE部署可能包括不同CE措施的组合。因此，在这个项目中，我们解决的问题是，地球系统将如何对CE测量的组合做出反应，以及不同的信号是否仍然可以归因于某种技术。在此背景下，我们将讨论环境污染措施的有效性如何取决于背景气候状态，以及部署的时间可能如何相关。此外，为了能够对环境污染的影响进行区域分析，以及对区域环境污染信号的检测和归因，将研究环境污染造成的稳健变化模式。这一点特别重要，因为区域极端气候与当地社区息息相关。此分析还将通知度量查找过程。此外，将在地球系统变化速度的范围内处理环境行政活动的终止问题，以便为生物影响评估研究提供资料。最后，由于评估气候对碳排放技术的响应的唯一工具是模型，我们认为对碳排放辩论的重要贡献是对关键模型不确定性的全面评估。这些将被量化，以确定度量的概率密度函数的变化，例如，给定不同的未来场景，通过某个阈值的概率。该项目的结果将对模型、情景和度量的不确定性下的联合缓解- ce情景进行全面评估，并将与SPP中的伙伴项目进行迭代讨论。

The main objective of the ComparCE project is a comprehensive assessment of the various Climate Engineering (CE) measures and emission-reduction efforts, taking into account uncertainties in the earth system model simulations on which the assessment is based. We want to address various urgent questions, that we feel are missing in the context of CE assessment so far. As a first and central step it will be investigated which assessment metrics and indicators are of importance in the CE context, and thus to the entire priority program, and how they differ from climate change assessment metrics. There has been research in this field for climate change but for the CE debate this assessment is missing. From exchanges with international CE research groups, it became clear, that a future deployment of CE would likely consist of a combination of different CE measures. Therefore in this project we address the question, of how the Earth system will react to a combination of CE measures and whether the distinct signals can still be attributed to a certain technique. In this context it will be addressed how the effectiveness of a CE measure depends on the background climate state, and how e.g. the timing of a deployment might be of relevance. Furthermore, robust patterns of changes due to CE will be investigated in order to enable regional analysis of CE impacts, as well as detection and attribution of signals of regional CE. This is of special importance since the regional climate extremes are of relevance for the local communities. This analysis will also inform the metrics finding process. Additionally, termination of CE will be addressed in the context of the rates of changes in the earth system to inform biological impact assessment studies. Finally, since the only tools to assess climatic responses to CE techniques are models, we feel that an important contribution to the CE debate is a thorough assessment of key model uncertainties. These will be quantified determining changes in the probability density functions of metrics e.g. the probability of passing a certain threshold given different future scenarios. Results of this project will provide a comprehensive assessment of joint mitigation-CE scenarios under uncertainty of models, scenarios and metrics, which will be discussed iteratively with partner projects in the SPP.