This project aims at embedding climate engineering into the context of established mitigation options. It is based on the hypothesis that most societies would not decide on climate engineering in isolation but rather under the impression of the feasibility of mitigation and adaptation options and an integrated view on the pros and cons of various technologies. This requires further research because costs, risk profiles and benefits of available options vastly differ. However the current scientific debate lacks such an integrated view. Climate engineering is typically analyzed more or less in isolation without reference to mitigation options. This project aims at closing this gap by comparing selected climate engineering options to strategies that rest on reducing emissions at their source and formulating conditions for their integration in a portfolio of response measures based on ethics and decision analysis. The project aims to determine under what points of view, supported by arguments from moral philosophy, does climate engineering have the potential to complement or even partly substitute mitigation measures, or whether based on our current knowledge it is more of an illusion than a remedy.
The project focuses on carbon dioxide removal options, in particular afforestation, enhanced weathering, and direct air capture, but will also look at stratospheric aerosol injection as a key solar radiation management option. For all technologies, techno-economic parameters will be defined in order to embed them in a decision analytic framework. Furthermore, impacts and side effects will be summarized to define risk profiles of the different technologies. Based on philosophical frameworks, various scenarios of normative assessments will be carried out. We define normative thresholds and rules of aggregation of technologies’ effects. This allows for an integrated assessment of mitigation and climate engineering given stabilization targets ranging from 1.5° to 3°C global mean surface temperature, and the formulation of preferable response strategies under various approaches to account for uncertainty in the outcomes of various technologies. By this means, a consistent analysis of synergies and conflicts between economic development, food and energy demand, climate change as well as climate policy in different world regions will be facilitated. In a nutshell, our research project will provide crucial information to societies and decision-makers, allowing them to weigh the consequences of embracing or neglecting climate engineering as well as giving them a concrete picture of the challenges and ethical trade-offs the different technological options imply.