ODEÓN workshop: co‐creation of research on climate intervention techniques through citizen engagement

A broad set of methods and technologies that aim to deliberately alter the climate system in order to alleviate the impacts of climate change. Most, but not all, methods seek to either (1) reduce the amount of absorbed solar energy in the climate system (Solar Radiation Management) or (2) increase net carbon sinks from the atmosphere at a scale sufficiently large to alter climate (Carbon Dioxide Removal). 'Climate intervention' is now recommended as the preferred terminology because it clearly states the problem in question (climate) and that solutions are not always necessarily related to 'engineering'. Also, it has been shown that non-scientists find this terminology easier to understand and hold less negative connotations with the phrase. This terminology was communicated to the attendees at the beginning of the workshop. The main objective of the workshop was to use the feedback from citizens to develop a co-creation approach for the research project, in which the research goals are informed or modified according to citizens' concerns. The workshop attendees included representatives of the environmental departments of local city councils and NGOs, such as Friends of the Earth and Engineers without Borders; MSc and PhD students in Aerospace Engineering and Atmospheric Physics; the Environment Office Manager of the University of Vigo; and social media influencers in environmental protection. The Social Council of the University of Vigo supported the workshop with a monetary contribution. The workshop began with Juan Añel and Laura de la Torre (principal investigators of the project) who presented a brief introduction on climate intervention techniques. This included showing different approaches for solar radiation management, carbon capture and chemical removal of methane, as well as key side effects. It also explained the physical and chemical fundamentals of such methods with basic, non-scientific language. They highlighted the current worldwide framework and state-of-the-art climate intervention research and governance, such as The Oxford Principles (https://www.geoengineering.ox.ac.uk/www.geoengineering.ox.ac.uk/oxford-principles). Finally, they showed the participants some preliminary ODEÓN research results on the potential impacts of sulphate aerosol injection (SAI) on the solar photovoltaic energy resource over the Iberian Peninsula. SAI is a climate intervention technique where sulphate aerosols are injected into the Earth's stratosphere, resembling the impacts of major volcanic eruptions. The presence of these aerosols reduces the amount of solar irradiance that reaches the Earth's surface, therefore lowering the temperature of Earth at the surface. Each group was given 45min to discuss these questions using sketches, drawings and paperboards. Afterwards, they were asked to report their choices to the rest of the room (Figure 1). The two groups decided to imagine futures in which two specific techniques were used at global scale. One group selected to focus on solar radiation management through the placement of Moon dust in the Lagrange's L1 point. The L1 point is a space between the Earth and the Sun where objects can be placed indefinitely due to the gravitational equilibrium. The dust particles act as light reflectors or absorbers that redistribute solar radiation—reducing the solar irradiance reaching the Earth's surface (providing a cooling effect). The other group selected the addition of chlorine to the atmosphere as their technique, which can increase the frequency of chemical reactions that reduce the overall concentration of methane (a potent greenhouse gas). As part of the workshop, some stakeholders were interviewed individually to produce a small documentary for outreach purposes of the ODEÓN project. These will be published in 2024 by UVigoTV, the online TV channel of the University of Vigo. They were asked about their previous knowledge of climate interventions before the workshop, their views on such techniques, the research developed under the project and, finally, their opinions on the workshop. Finally, Juan Añel presented on the planning of the research project, prospective topics and pending work. The attendees suggested that the study of the potential impacts of climate intervention on energy and air quality could be complemented, or even replaced by other studies, such as impacts on precipitation and agriculture, which they perceived as highly relevant for Spain. Attendees felt this would improve the outreach of our research, as they are topics that the general public is more familiar with and more closely impact their daily life. It was agreed that as Spain is highly dependent on agriculture and tourism, understanding the economic impact of climate interventions on these sectors would be crucial. It was quite surprising from the organisers' point of view that the attendees were not directly against funding research on climate intervention, despite the known views of some sectors (e.g., the Solar Geoengineering Non-Use Agreement) who are against such research. When this was highlighted by the research team, some participants acknowledged that they felt funding research into climate interventions was not a main priority for climate research. However, they were pleased that a citizen engagement workshop was held and that they were consulted on the design of the research. The workshop was a successful experience, and the representation from a variety of stakeholders provided different views on the perception and application of climate intervention techniques. The discussion spanned impacts on ocean life, air quality, governance and inequality issues. Regarding future steps, a second workshop is expected to be held in 2024, with a different, larger group of stakeholders from diverse backgrounds. A learning outcome to consider for the next workshop is to frame the problem without imposing prior perceptions or constraints on the attendees, for instance, without highlighting the side effects of climate intervention techniques. We speculate that sharing the unexpected nature associated with the 'illusion of control' before engagement exercises may have resulted in a more critical audience response to technology testing. Finally, in the spirit of the co-creation research approach, the goals of the ODEÓN project have been modified, and additional research on water sources, atmospheric rivers and precipitation will be prioritised over the study of impacts on air quality. This has been chosen as the most feasible of the workshop suggestions, given the expertise of the research team, budget and time constraints. J.A.A. wrote the first draft of the manuscript. Then all the authors provided feedback, criticism, and edits to the different versions of the manuscript. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.