Physicist Proposes New Solution for Global Warming

Published August 1, 2006

In the summer blockbuster of 1998, Armageddon, Bruce Willis led a crew of courageous malcontents on a space expedition to destroy an asteroid on a collision course with the Earth. The movie is science fiction, of course, but the concept that man could employ technology to avert such a natural disaster is anything but fantasy. Research is underway on several fronts to prepare to deflect our inevitable appointment with an asteroid.

This summer’s catastrophe movie, An Inconvenient Truth, casts man as villain rather than problem solver. However, if one accepts the premise Al Gore promotes in the film–that disasters are just around the corner as a consequence of industrialization–one must wonder: Where are the technological knights in shining armor?

Enter Dr. Gregory Benford, a science fiction author and physicist on the faculty of the University of California at Irvine Department of Physics and Astronomy. Benford has been an advisor for NASA, the U.S. Department of Energy, and the White House Council on Space Policy. At the June 2006 Skeptics Society conference at the California Institute of Technology, Benford, with this reporter in attendance, proposed a plan to shield the Earth from the sun’s radiation–controlling the climate on purpose instead of by accident.

Benford’s proposal involves suspending thousands of one-micron particles high in the stratosphere (approximately 82,000 feet above the Earth) to reflect solar radiation. Benford formulated the plan with colleagues from Stanford University and Lawrence Livermore National Laboratory.

Kyoto Agreements Flawed

Benford’s widely publicized January 21, 2005 San Diego Union-Tribune article with Martin Hoffert, “Fear of Reason,” criticized Michael Crichton’s climate contrarian novel State of Fear on several fronts. That led to expectations Benford might use the Skeptics address to promote plans for limiting carbon dioxide (CO2) emissions. Instead, he came out swinging in the other direction, suggesting drastic limits on fossil fuel combustion intended to stabilize atmospheric CO2 were not likely to be adhered to and were undesirable.

Benford dismissed as unrealistic the possibility that alternative forms of energy could supplement nuclear power to meet the world’s foreseeable energy needs for the next 50 years. He acknowledged the possibility that people may be able to remove carbon dioxide from the atmosphere and sequester or store it underground in porous rock formations, but said he sees more promise in the unexplored frontier of directly managing solar radiation.

Cooling Effect Well-Known

First, Benford revisited a plan he had suggested earlier to control solar radiation by placing a 1000-kilometer-wide mylar lens between the Earth and sun. But Benford’s newest idea is even simpler: Creating a particulate shield that takes advantage of the same kind of modeled climate responses to relatively minor changes in atmospheric composition that are driving belief in manmade climate change in the first place.

The cooling effect of atmospheric sulphate aerosols has led many climate modelers to suggest these particles have been counteracting global warming. Despite much research supporting this cooling effect, global warming alarmists have downplayed the suggestion that this knowledge could be employed usefully. Stephen Schwartz, an atmospheric chemist at Brookhaven National Labs, said, “This is an attractive thought, but it cannot work in the long run because aerosols are so short-lived in the atmosphere, whereas greenhouse gases accumulate over time.”

But Benford and his scientific team, expanding on research suggesting a significant albedo, or reflection, effect of one-micron sulphates, suggest lofting a shield of designer particles–one possibility being diatomaceous earth, commonly mined for filtration and pest control–crushed uniformly to the requisite particle size. Benford suggests the shield could be deliberately fashioned to increase solar reflection in the ultraviolet (UV) spectrum, thus limiting warming and the potentially harmful effects of UV radiation on plants and animals while maintaining the wavelengths beneficial to photosynthesis.

By choosing the right particles and height in the atmosphere, the principal downside of sulphate aerosols–acid rain–can be avoided, Benford maintains. Dispersing the shield in the stratosphere would place it largely above the water vapor cycle.

Much Less Costly

Benford thinks the shield could be established and maintained for the relatively paltry sum of a billion dollars a year. If so, direct management of solar radiation could accomplish an order of magnitude more than the Kyoto treaty while costing several hundred times less.

Benford proposes testing the idea with a relatively small-scale experiment over the Arctic, where he believes stratospheric circulation patterns would confine a first deposition of particles, allowing their effect to be carefully studied. Some financially capable sources were sufficiently impressed by the presentation in Pasadena to approach Benford to discuss funding the research, according to Dr. Michael Shermer, the conference host and publisher of Skeptic magazine.

A great deal of research must be conducted before Benford’s idea could be implemented if it should prove to be feasible. Nevertheless, his supporters assert, if there truly is an impending climate change problem, why not investigate means to fix it directly and in a manner that does not severely punish world economies?

Benford does not foreswear some Earth-based strategies–such as making roads and buildings in lighter colors to reflect more solar radiation–or discount the value of energy efficiency and improved alternatives to fossil fuels. But he is convinced by energy demographics that, rather than limit fossil fuel consumption, we should have near-term technologies on the shelf to shield the world from severe warming should any of the worst-case scenarios actually appear likely.


Brian Bishop ([email protected]) is Rhode Island State Director for the Alliance for America and director of Rhode Island Wise Use.