Developing a foundation for science-based decision-making on climate intervention

Eight of the top ten warmest years on record have come in the last decade, and 2020 may become the hottest year ever. Extreme weather events such as hurricanes and wildfires are becoming more commonplace. Satellite images show rising risk that the West Antarctic ice sheet will collapse, driving up sea levels. Experts predict these and other changes in the climate could create hundreds of millions of climate migrants by 2050.

As temperatures rise, so does the possibility that Earth’s climate system will cross critical thresholds, resulting in abrupt changes with catastrophic consequences for people and the natural systems they rely on. It is possible that some of these changes could occur in the next 10-30 years, faster than even the most aggressive measures for reducing or removing greenhouse gases are likely to take effect.

International climate policy has primarily focused on reducing greenhouse gas emissions and more recently on measures to actively remove them from the atmosphere. While essential, these measures may act too slowly to address near-term hazards. But scientists and policymakers have begun to consider more rapid measures to reduce warming such as increasing the reflection of sunlight from the atmosphere by dispersing particles in the stratosphere or using sea salt mist to brighten clouds – solar climate intervention (SCI).

In our last piece together, we discussed a paper by international climate law experts Sue Biniaz and Dan Bodansky that examined the ability of existing international bodies to evaluate and govern solar climate intervention. They found that any decision-making regarding SCI would require a scientifically rigorous assessment of “two safeties,” the safety of the global climate and the safety of possible interventions to reduce or arrest warming.

In their new paper published by C2ES and SilverLining, Biniaz and Bodansky discuss the nature of the research required to support this science-based decision-making and address common objections to undertaking it.

Currently, there are enormous gaps in our knowledge about near-term climate risks and potential climate interventions. Research supplies information for governments, stakeholders, and the general public to understand the likely outcomes associated with various responses, including interventions, in order to make decisions about options for protecting communities and sustaining a stable climate.

Today, we do not know enough. According to the authors, to make decisions that best promote safety, we must better understand: 1) the risks of abrupt changes, 2) the efficacy, feasibility, and safety of potential interventions, and 3) the comparative risk and benefits of different types of intervention versus no intervention at all. This, in turn, requires substantial research in both climate prediction and study of specific interventions with significant investments in earth system observations, climate models and data studies, technology R&D, small-scale experiments, and technology prototypes and operational designs.

Climate change is a fast-moving problem that is already causing substantial loss of life and health and massive economic harm. Research to better predict climate and catastrophic extremes and changes is of enormous value. Starting from an incredibly low base of knowledge, better understanding of potential rapid responses to arrest or reduce warming is essential.

In the past, a number of objections have led to suppression of this research. The authors address many of these objections, thoughtfully and compellingly. Broadly speaking, though, no objections can overcome the justice, economic and safety imperatives of providing more and better information on options for responding to climate change.

As Biniaz and Bodansky highlight in the paper, the COVID-19 pandemic has demonstrated the importance of preparation and science-based decision-making to promote public safety. We must invest in climate intervention research now to be better prepared and avoid the worst outcomes in another global crisis.

Research that improves our understanding of the risks of catastrophic changes and our ability to respond safely and effectively to them can generate enormous social benefits.

It will contribute to more democratic and equitable decision-making on climate. It will promote social justice by identifying new avenues to reduce climate change risk for people living in vulnerable communities. It will reduce the risk of geopolitical tensions over climate interventions caused by uncertainty, mistakes, or rogue actors. Perhaps most importantly, It will better enable us to sustain a safe climate for future generations.