Solar Radiation Management Techniques Research Articles

Determining our climate policy future: expert opinions about negative emissions and solar radiation management pathways

Negative emissions technologies and solar radiation management techniques could contribute towards climate stability, either by removing carbon dioxide from the atmosphere and storing it permanently or reflecting sunlight away from the atmosphere. Despite concerns about them, such options are increasingly being discussed as crucial complements to traditional climate change mitigation and adaptation. Expectations around negative emissions and solar radiation management and their associated risks and costs shape public and private discussions of how society deals with the climate crisis. In this study, we rely on a large expert survey (N = 74) to critically examine the future potential of both negative emission options (e.g., carbon dioxide removal) and solar radiation management techniques. We designed a survey process that asked a pool of prominent experts questions about (i) the necessity of adopting negative emissions or solar radiation management options, (ii) the desirability of such options when ranked against each other, (iii) estimations of future efficacy in terms of temperature reductions achieved or gigatons of carbon removed, (iv) expectations about future scaling, commercialization, and deployment targets, and (v) potential risks and barriers. Unlike other elicitation processes where experts are more positive or have high expectations about novel options, our results are more critical and cautionary. We find that some options (notably afforestation and reforestation, ecosystem restoration, and soil carbon sequestration) are envisioned frequently as necessary, desirable, feasible, and affordable, with minimal risks and barriers (compared to other options). This contrasts with other options envisaged as unnecessary risky or costly, notably ocean alkalization or fertilization, space-based reflectors, high-altitude sunshades, and albedo management via clouds. Moreover, only the options of afforestation and reforestation and soil carbon sequestration are expected to be widely deployed before 2035, which raise very real concerns about climate and energy policy in the near- to mid-term.

Living the global social experiment: An analysis of public discourse on solar radiation management and its implications for governance

Solar radiation management techniques are a class of geoengineering methods designed to reflect some of the inbound sunlight back into space with the intended effect of arresting further warming of the planet and thus counteracting global warming. In this article we examine current debates on solar radiation management governance, clarifying a number of assumptions that persist and why these require further scrutiny. Building on existing research we articulate a more critical role that the social sciences should be playing in public engagement with solar radiation management. We develop a deliberative focus group methodology that aims to open up deliberation on the technology, focusing explicitly on the kinds of world that its deployment would bring into being. Our findings, based on an analysis of public discourse, suggest that solar radiation management would be publicly acceptable only under very specific, and highly contingent, conditions. Given the sensed implausibility of these conditions being realised in the real world, we set out the implications for solar radiation management governance. We explain why solar radiation management was perceived as likely to create a particular kind of world, one with an increased probability of geopolitical conflict, a new condition of global experimentality, and major threats to democratic governance. How to bring these issues into solar radiation management governance entails an important but challenging role for the social sciences.