Mainstream politics, by definition, is ill equipped to imagine fundamental change. But last December in Paris, 196 governments agreed on the need to limit global warming to 1.5 degrees Celsius above pre-industrial levels — an objective that holds the promise of delivering precisely such a transformation. Achieving it will require overcoming serious political challenges, reflected in the fact that some are advocating solutions that will end up doing more harm than good.
One strategy that has gained a lot of momentum focuses on the need to develop large-scale technological interventions to control the global thermostat. Proponents of geo-engineering technologies argue that conventional adaptation and mitigation measures are simply not reducing emissions fast enough to prevent dangerous warming. Technologies such as "carbon capture and storage" (CCS), they argue, are necessary to limit damage and human suffering.
The Intergovernmental Panel on Climate Change seems to agree. In its fifth assessment report, it builds its scenarios for meeting the Paris climate goals around the concept of "negative emissions" — that is, the ability to suck excess carbon dioxide out of the atmosphere.