Regional climate engineering by radiation management: Prerequisites and prospects

Abstract

Radiation management (RM), as an option to engineer the climate, is highly controversial and suffers from a number of ethical and regulatory concerns, usually studied in the context of the objective to mitigate the global mean temperature. In this article, we discuss the idea that RM can be differentiated and scaled in several dimensions with potential objectives being to influence a certain climate parameter in a specific region. Some short-lived climate forcers (e.g., tropospheric aerosols) exhibit strong geographical and temporal variability, potentially leading to limited-area climate responses. Marine cloud brightening and thinning or dissolution of cirrus clouds could be operated at a rather local scale. It is therefore conceivable that such schemes could be applied with the objective to influence the climate at a regional scale. From a governance perspective, it is desirable to avoid any substantial climate effects of regional RM outside the target region. This, however, could prove impossible for a sustained, long-term RM. In turn, regional RM during limited time periods could prove more feasible without effects beyond the target area. It may be attractive as it potentially provides the opportunity to target the suppression of some extreme events such as heat waves. Research is needed on the traceability of regional RM, for example, using detection and attribution methods. Incentives and implications of regional RM need to be examined, and new governance options have to be conceived.

Articulating Geoengineering: Identifying an Understanding of Geoengineering Technology Through theCrutzen +10 Special IssueForum

“…What is predicted as possible : MacCracken (2016) suggests that “potential implementation is intended to reduce the severity of human-induced global warming by keeping the climate near to present or recently past conditions” (p. 652). Quaas et al (2016) suggest that regardless of continued climate engineering research, the use of climate engineering techniques may be inevitable, as desperate governments will enact them anyway (p. 619).…”

“…They also suggest examples of this, stating “Pongratz et al [2012] found that a deployment of sunshade geoengineering would increase global crop yields compared to a scenario without sunshade geoengineering by reducing the heat stress associated with GHG warming” (p. 96), and that “Nowack et al [2016] show that sunshade geoengineering could reduce ultraviolet radiation at the surface and increase surface ozone, which is harmful to human, animal, and plant health” (p. 97). Additionally, Quaas et al (2016), suggest that “regional RM during limited time periods could prove more feasible without effects beyond the target area. It may be attractive as it potentially provides the opportunity to target the suppression of some extreme events such as heatwaves.…”

“…Geoengineering is new and has some risk factors : Irvine et al (2017) offer that “given that solar geoengineering is being considered as a means to reduce the risks and impacts of climate change this begs the question: What potential deployments of geoengineering could best reduce these risks?” (p. 99). Quaas et al (2016) admit that “[SRM], as an option to engineer the climate, is highly controversial and suffers from a number of ethical and regulatory concerns” (p. 623). Finally, Reynolds et al (2016) use a quote from leading geoengineering researcher, Ken Caldeira, stating, “only fools find joy in the prospect of climate engineering” (p. 564).…”

Reflecting upon 10 years of geoengineering research: Introduction to the Crutzen + 10 special issue

“…Several contributors to this special issue highlight the design aspect of the geoengineering discussion: While Low discusses the potential for using anticipatory foresight as a way to engage stakeholders in visioning exercises for the kinds of futures "we" want, Quaas et al [2016] and MacCracken [2016] discuss the potential for the design of targeted and regionally differentiated geoengineering approaches. Quaas et al focus on regional scale economic incentives to undertake regional solar geoengineering and conclude that this may be attractive since it potentially provides the opportunity to target the suppression of some extreme events such as heatwaves.…”

Challenges and Opportunities for Integrated Modeling of Climate Engineering

“…temperature and precipitation. Especially for SRM, then, models should move away from assessing global mean temperature as the unique target, when evaluating SRM options, and include a wider set of criteria, in addition to the greater level of regional differentiation 46,47 . Inclusion of regional climate modules would be an important first step.…”