The urgency of addressing climate change has led to the exploration of solar geoengineering (SGE)—a collection of technologies that cool the planet by reflecting a fraction of sunlight back into space. One of the most prominent concerns with SGE is that it may crowd out greenhouse gas mitigation efforts. This paper examines how advances in SGE technologies may impact mitigation. We conduct a social dilemma experiment with treatments that vary how effective SGE is at reducing climate damages and the level of certainty about its effects. Results indicate SGE generally leads to increased cooperation on mitigation, but importantly, we find that mitigation levels decrease significantly as SGE technologies become more effective and less uncertain. At an individual level, agents that stand to benefit the most tend to decrease mitigation, while those that are vulnerable to SGE act to diminish the role of SGE by increasing mitigation.
Cherry et al. (Tue,) studied this question.