An Evaluation of Space-Based Geoengineering Approaches

Space-based geoengineering has been proposed as a lower-risk but higher-cost alternative to terrestrial solar irradiation management approaches such as stratospheric aerosol injection. However, due to its high mass and therefore high number of required rocket launches, existing approaches have not been considered as serious alternatives. Emerging alternatives such as ultra-low mass sunshade designs and in-space manufacturing using in-situ resources might change this verdict. Hence, the objective of this MSc. thesis is to evaluate emerging approaches. To this end, an extensive literature review identified 18 geoengineering evaluation criteria and two sustainability frameworks, revealing several research gaps, such as the global warming potential of the high number of rocket launches, which was subsequently addressed. Due to the added complexity of in-space manufacturing using in-situ resources at scale, and increased overall weight of in-space resource-based space systems, it is concluded that an advanced Earth-manufactured concept such as the Realistic Sunshade System seems more feasible and rational short- and midterm.