Feasibility of Space-Based Monitoring for Governance of Solar Radiation Management Activities

Substantive research has begun into proposed schemes to synthetically increase the earth's albedo (reflectivity) as a potential improvised measure to mitigate impacts of global warming if emission reductions are not sufficient or if the climate response is more extreme than anticipated. The authors of this paper do not take a position on whether Solar Radiation Management (SRM) should be used as a strategy to respond to climate change. However, future international agreements regarding development, testing, and implementation of SRM schemes will not be enforceable without effective means of monitoring and verification, especially since the relatively low cost of injecting reflective particles such as sulfur into the upper atmosphere will allow individual nations - perhaps even private corporations or other groups - to experiment on their own. This paper discusses monitoring requirements and the feasibility of space-based remote-sensing systems for detecting and monitoring particle injection into the upper atmosphere. Our preliminary findings suggest that detecting clandestine unilateral small-scale precursor particle-injection with satellite instruments may not be practical. This conclusion suggests that future treaty negotiations will need to consider alternative means of monitoring such activities.