Economists need to embrace research on solar geoengineering technologies
In their Policy Forum “Opportunities for advances in climate change economics” (15 April, p. 292), M. Burke et al. highlight three areas of climate change economics research: social cost of carbon, climate policy impacts, and developing economies. They overlook an important avenue of research that affects all three: climate engineering technologies, in particular solar radiation management (SRM).
SRM is an engineered change in Earth’s radiative forcing in an effort to reduce climate changes (1). Direct costs are low (2). SRM acts quickly (years) so it reduces part of the effective inertia of the climate system, profoundly altering the dynamics of any climate policy. SRM would substantially change the profile of climate impacts, disconnecting temperature from other changes caused by CO2, such as ocean acidification. It would also alter the distribution of climate impacts and policy choices across countries (3). Importantly, SRM would introduce new risks to the equation (4).
Integrated assessment models have a damage function that is largely calibrated in terms of temperatures. Recent versions also add sea-level rise (5). This is a good approximation when damages from carbon concentrations and temperature are linked. SRM would change this relationship by reducing temperature without lowering carbon concentrations. Integrated assessment models must recognize the newly differentiated impacts. Naïvely introducing SRM into these models without further consideration would bias the results toward implementation of SRM.
SRM is an important part of the future climate policy research agenda, as illustrated by the latest National Academy of Sciences report (6, 7). Economists need to embrace research on SRM technologies, recognize their capacity to disrupt the climate policy agenda, focus on understanding the new impacts and risks introduced, and integrate this new understanding into models and policy design.
Full text: “Modeling the effects of climate engineering”
Keith, David, Gernot Wagner, and Juan Moreno-Cruz. “Modeling the effects of climate engineering.” Science 352 (6293): 1526-7 (24 June 2016) 10.1126/science.aag1630.