Dimming the Sky

As climate change accelerates, some scientists are researching ways to alter our climate to slow down warming. But the method, called solar geoengineering, comes with some serious risks. 

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  • Gabrielle Sierra
    Director, Podcasting

Asher Ross - Supervising Producer

Markus Zakaria - Audio Producer and Sound Designer

Rafaela Siewert - Associate Podcast Producer

Episode Guests
  • David Keith
    Professor, Applied Physics, Harvard John A. Paulson School of Engineering and Applied Sciences, Professor of Public Policy, Harvard Kennedy School
  • Shuchi Talati
    Fellow, Solar Geoengineering Research, Governance, and Public Engagement, Union of Concerned Scientists
  • Gernot Wagner
    Climate Economist, Columbia Business School

Show Notes

Given the grim reality of the climate crisis, some scientists are seeking to artificially manipulate the environment to limit the impacts of global temperature rise. One idea is to release aerosols into the stratosphere to reflect sunlight back into space. While the method could buy the world some time to lower carbon emissions, it presents serious scientific and political risks.


Note: This episode was rebroadcast on September 30, 2020.


From CFR


The World May Need Geoengineering, and Geoengineering Needs Governance,” Terrence Mullan


Geoengineering Is Inevitable in the Face of Climate Change. But at What Cost?,” Stewart M. Patrick


The Anticipatory Governance of Solar Radiation Management,” Oliver Geden and Susanne Droge


Read More


Can Bringing Back Mammoths Help Stop Climate Change?,” Smithsonian Magazine 


The Next Big Volcano Could Briefly Cool Earth. NASA Wants to Be Ready.,” New York Times


White House Urges Research on Geoengineering to Combat Global Warming,” New York Times


The Very Optimistic New Argument for Dimming the Sky,” Atlantic


What Happens If We Stop Solar Geo-Engineering—and Then Suddenly Stop?,” Atlantic


Risks of Controversial Geoengineering Approach ‘May Be Overstated’,” Scientific American


Watch or Listen


This Climate Pioneer Is Trying To Stop The Arctic From Melting,” VICE News


Can geoengineering save the planet from climate change?,” CBC’s The National


Could solar geoengineering counter global warming?,” Economist


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