Strategic logic of unilateral climate intervention

Climate change and unabated greenhouse gas emissions are increasing the possibility that the world will turn to climate intervention to curb ever-increasing global temperatures. This paper uses game theory to elucidate the conditions that might make a state more or less likely to begin unilateral, as opposed to internationally coordinated, climate intervention (UCI). We solve this game for several specific scientific, economic, and climatological conditions that change the likelihood of a government starting its own climate intervention deployment program without the participation of the broader international community. Specifically, we demonstrate that the plausibility of UCI is linked to perceptions of three key elements: (1) the effectiveness of climate intervention strategies, (2) the sensitivity of specific governments to punishment by other states, and (3) satisfaction with climate and weather in the present. We conclude by discussing how this formal game theory model informs the design of future Earth system model simulations of UCI, international agreements related to climate intervention, and the development of solar climate intervention technologies.