Labont seminars: Climate Crisis and Future Generations
University of Turin, 22 March 2022
Webex h 4:00-6:00 pm
Daniele Visioni (Cornell University), “Climate engineering: what do we know, what do we still need to know, and should we know it?”
Climate engineering (or climate intervention, or geoengineering) is a topic that is gaining prominence in mainstream climate policy discourse, especially as the chance of remaining below 1.5 ºC of warming above preindustrial levels fades. It is defined as any deliberate, large scale intervention in the climate system aimed at reducing the harmful effects of the increase in greenhouse gases. As an umbrella term, it usually includes both large scale methods of CO₂ removal from the atmosphere (Carbon Dioxide Removal, CDR) and methods aimed at reducing the incoming sunlight in order to cool the planet (Solar Radiation Modification, SRM). In this talk, I will give an overview of both CDR and SRM methods, and focus on the diverse sets of challenges they present: technological, ethical and related to governance. CDR or “negative emissions” are now present in almost all “net-zero” plans from both governments and private sector actors, and all major scenarios from the Intergovernmental Panel on Climate Change (IPCC) include some; but problems with their probable environmental impacts, land use, trade-offs with food production and technical challenges with their scalability need to be addressed, and uncertainties abound. SRM, while still at the fringe, may offer on the other hand a “cheap and easy” temporary solution capable to ameliorate some of the risks, but far more research would be necessary to understand its potential, limits, and novel risks, and some burning questions remain: whose hand would be on the thermostat, whose consent should be asked before SRM could even start, and can a global governance system capable of ensuring a “just” deployment ever be developed?