GeoengineeringWe need laws on geoengineering, and soon

Humans have been accidentally altering the planet’s climate for thousands of years. Soon, it may be possible alter it intentionally.

The deliberate, large-scale manipulation of climate is called geoengineering. The term encompasses a variety of proposals, from pulling carbon dioxide out of the atmosphere to reflecting sunlight back into space in an attempt to slow the earth’s warming. Global geoengineering tactics haven’t yet been deployed, but as climate change starts to spin out of control, support for some forms of geoengineering seems to be growing.

However, there’s a lot that can go wrong when it comes to modifying the complex global climate system, and the world is not prepared for the problems that might result. A new book coming out April 21 points out the major holes in national and international geoengineering regulation, and lays out a framework for improvement. The book, titled Climate Engineering and the Law: Regulation and Liability for Solar Radiation Management and Carbon Dioxide Removal, was co-edited by Michael Gerrard from Columbia’s Sabin Center for Climate Change Law and Tracy Hester, a graduate of Columbia Law School who now teaches at the University of Houston Law Center. Gerrard is also chair of the faculty of the Earth Institute.

The book draws a distinction between different types of climate engineering strategies. Techniques that simply pull carbon dioxide from the air are unlikely to have global side effects, so they don’t need to be regulated internationally, Gerrard says.

However, solar radiation management projects, which would block some sunlight from reaching the earth—for instance, by dumping tiny reflective particles into the upper atmosphere—could have harmful consequences around the globe. Famously, the 1991 Mount Pinatubo volcanic eruption spewed so much ash into the air that it temporarily cooled the global thermostat by one degree Fahrenheit. However, the eruption is also thought to have shifted precipitation patterns, causing floods along the Mississippi River and droughts in the African Sahel. Deploying solar radiation management techniques could have similar side effects. Such proposals don’t receive much support from the scientific community.

Who decides whether a geoengineering project should go forward, and what approvals should be required? What happens if something does go wrong—who is at fault, and what compensation should be provided? These are just some of the questions addressed in the book. State of the Planet’s Sarah Fecht interviewed Gerrard to find out more.