Climate Action: The Feasibility of Climate Intervention on a Global Scale

Today’s CO₂ emissions are 60% greater than those in 1992 when Rio Earth Summit participants first agreed to act to prevent climate change. The failure to curb emissions is not due to a dearth of technical know-how; the climate intervention toolbox is full of strategies from mitigation to geoengineering and adaptation. Rather, it is due to a lack of political will exacerbated by gaps in our understanding of the complexity that reigns over the earth’s climate system. As we creep ever closer to crossing planetary thresholds and tipping points, time is running out to take the requisite actions to avoid global crises. Future efforts to slow, stabilize or reverse climate change must involve deployment of all possible interventions. The technical and political feasibility of climate action at a global scale rests on deep knowledge of how the climate system can be adjusted by these interdependent tools. Geoengineering entails two broad classes of endeavors with entirely different aims: carbon dioxide removal from the atmosphere and albedo modification to reduce the amount of sunlight hitting the earth’s surface. Many geoengineering options are the ultimate exercise of the engineering mentality deployed at massive scales in both time and space to buy time, despite the many actions that could be employed to actually solve the climate problem. This chapter explains and analyzes from a science and engineering perspective the multitude of available climate tools and considers potential challenges, uncertainties, and unexpected consequences of engineering climate adjustments at a global scale.