Solar Radiation Management

This discussion was co-authored by J. Eric Bickel, Assistant Professor, The University of Texas at Austin.

Measures to reduce greenhouse gas (GHG) emissions have dominated public discourse about responses to man-made climate change. However, major institutional and political hurdles dim the prospects for controlling emissions.

Solar Radiation Management (SRM) appears to promise at least some capacity to offset manmade warming. SRM would seek to manage physical processes that reflect sunlight back into space. For example, researchers have envisioned adding to the layer of aerosols already present in the lower stratosphere. All else remaining equal, global mean temperatures would fall even though GHG levels would not. By lessening the rise in temperature, SRM might avoid some of the risks of global warming.

No one is proposing to deploy SRM systems at this point. The technologic concepts have not yet been proven to be either effective or safe. And an eventual decision to deploy SRM would probably require a good deal of hard bargaining among the world’s major powers.

Nonetheless, SRM might greatly lower the damages that could be caused by warming as well as the costs of the GHG control measures that would otherwise be justified to avoid those damages. Compared to the scale of the possible benefits, the costs of an R&D effort are trivial. In sum, if climate change poses a serious potential threat, then, it is prudent for the United States to pay the very modest costs of an R&D program to learn more about SRM’s potential benefits and risks.  

What is the potential for SRM as a tool to address climate change?  Should SRM research be part of the U.S. policy approach to GHG emissions and climate change issues?