Nonprofit publishes road map for solar geoengineering research to inform deployment decisions

A San Francisco nonprofit, Reflective, has published a research road map for solar geoengineering, specifically stratospheric aerosol injection (SAI). The plan outlines experiments, studies, and infrastructure needed to reduce scientific uncertainties before any potential deployment. This effort aims to provide data for policymakers and researchers to make informed decisions about whether and how to use SAI to counteract climate change. The road map does not advocate for deployment but argues that research should proceed to avoid rushed decisions later.

The road map estimates that a coordinated research program would take about a decade and cost $370 million, while an uncoordinated effort could take 20 years and nearly $1.4 billion. The plan includes lab experiments, computer simulations, and observational tools to study baseline stratospheric conditions. It also proposes outdoor experiments releasing sulfur dioxide or similar materials into the stratosphere to observe effects. These experiments are contentious, with critics arguing that such a powerful technology could never be governed equitably.

Key technical uncertainties remain, such as how particles would behave in the stratosphere, whether they would spread evenly or clump and fall out. The road map also highlights the need to study regional impacts, including effects on ocean circulation, ice sheets, and crop yields. Reflective’s plan builds on its earlier work, including an open-source solar geoengineering simulator and a database of scientific unknowns. The organization has raised over $20 million and funded multiple research groups to advance this work.

The governance and ethical questions surrounding SAI are as significant as the technical challenges. Critics argue that decisions about deploying a planet-altering technology would inherently create winners and losers, raising questions about who controls it and whose interests it serves. While the road map focuses on scientific and engineering hurdles, it does not resolve these broader concerns. Engineers and researchers may need to engage with these questions if SAI moves closer to reality.