Fixing the Sky (42 page)

He was clearly interested in both inadvertent climatic effects—such as might be created by industrial emissions, rocket exhaust gases, or space experiments gone awry—and purposeful interventions, whether peaceful or done with hostile intent. Echoing von Neumann's 1955 warning about technology, Wexler continued: “Even in this day of global experiments, such as the world-wide Argus electron seeding of the Earth's magnetic field at 300 miles height, man and machinery orbiting the Earth at 100 miles seventeen times in one day, and 100 megaton bombs—are we any closer to some idea of the approaches which could lead to an eventual ‘solution' [to the problem of climate control]?” (3). He noted “a growing anxiety” in the public pronouncements that “Man, in applying his growing energies and facilities against the power of the winds and storms, may do so with more enthusiasm than knowledge and so cause more harm than good.”
⁷²

Wexler was well aware that any intervention in the Earth's heat budget would change the atmospheric circulation patterns, the storm tracks, and the weather itself, so, as he pointed out, weather and climate control are not two different things. After presenting some twenty technical slides on the atmosphere's radiative heat budget and discussing means of manipulating it, Wexler concluded with a grand summary of highly speculative techniques to heat, cool, or otherwise restructure the atmosphere:

One of the most stunning aspects of Wexler's lectures was his awareness that catalytic reactions of chlorine and bromine could severely damage the ozone layer. Wexler was concerned that inadvertent damage to ozone might occur if
increased rocket exhaust polluted the stratosphere or if near-space “seeding” experiments went awry: “The exhausts from increasingly powerful and numerous space rockets will soon be systematically seeding the thin upper atmosphere with large quantities of chemicals it has never possessed before or only in small quantities.”
⁷⁴
He was also concerned that the cold war and the space age might provide rival militaries with both the motivation and the wherewithal to damage the ozone layer. He cited a 1961 study by the Geophysics Corporation of America on possible harm to the Earth's upper atmosphere caused by the oxidizers in rocket fuel. He was also aware that Operations Argus and Starfish, Project West Ford, and Project High Water constituted recent significant interventions in the near-space environment that were accompanied by unknown and unquantified risks.

On the topic of purposeful damage, Wexler turned to the 1934 presidential address to the Royal Meteorological Society, in which the noted geoscientist Sydney Chapman had asked, “Can a hole be made in the ozone layer?”
⁷⁵
That is, can all or most of the ozone be removed from the column of air above some chosen area? Chapman was thinking of an event that would provide a window for astronomers to extend their observations some hundreds of angstroms farther into the ultraviolet without the interference of atmospheric ozone. Possible health effects of human exposure to shortwave radiation did not appear to Chapman to be an important issue, since the hole he was contemplating would be localized, probably in a remote area (he suggested Chile), and would be short-lived, somewhere between a day and an hour, timed for the benefit of astronomers only. Cutting such a hole, Chapman continued, would require “the discharge of a deozonizing agent” perhaps by airplanes, balloons, or rockets. Chapman proposed two possibilities: a large amount of a one-to-one destructive agent such as hydrogen that would reduce O
₃
molecules to O
₂
or “some catalyst which, without itself undergoing permanent change, could promote the reduction of large numbers of ozone molecules in succession” (134). Although the choice of the agent would have to be left to the chemists, Chapman concluded that “the project of making a [temporary] hole in the ozone layer [a 90 percent reduction for the benefit of astronomers] does not seem quite impossible of achievement” (135).

In November 1961, Wexler gathered weather bureau staff for a briefing on ozone depletion and circulated this memo, titled “Deozonizer”:

Bill Malkin suggested that Wexler might wish to raise the possibility with the country's national defense research arm, “that serious consideration be given to the possibility of artificially and temporarily altering (up or down) the ozone concentration over an area, as a most effective weapon.”
⁷⁷
Using the radiation model of Syukuro Manabe and F. Möller, Wexler was able to calculate a catastrophic 80°C (144°F) stratospheric cooling that would occur with no ozone layer.
⁷⁸

Seeking further advice on how to cut a “hole” in the ozone layer, Wexler turned to chemist Oliver Wulf at Caltech, who suggested that “from a purely chemical viewpoint, chlorine or bromine might be a ‘deozonizer.'”
⁷⁹
Wulf and Wexler exchanged numerous letters between December 1961 and April 1962 and met face-to-face in March, and Wulf met with Chapman in April. All these exchanges point to the conclusion (a stunning one, given the received history of ozone depletion) that chlorine or bromine atoms might act in a catalytic cycle with atomic oxygen to destroy thousands of ozone molecules. For example, Wulf wrote in early January 1962, “chlorine or bromine photosensitized decomposition [of ozone] might come closest to a reaction in which a small amount of added material would cause a relatively large amount of decomposition.”
⁸⁰
Wexler replied immediately, adding that he even had a delivery system in mind “à la West Ford dipoles” but had “no intention of suggesting or backing any such proposal.”
⁸¹

Wexler estimated that a 100-kiloton bromine “bomb” would destroy all ozone in the polar regions, and four times that amount would be needed near the equator. In a handwritten note composed in January 1962 he scrawled the following (figure 7.6):

And in another note (figure 7.7):

These are essentially the basis of the modern ozone-depleting chemical reactions.

7.6 (
top
) Harry Wexler's handwritten note on ozone depletion, January 1962. (WEXLER PAPERS)

7.7 (
bottom
) Harry Wexler's handwritten note on bromine reactions, January 1962. (WEXLER PAPERS)

Wexler's rough note of December 20, 1961, jotted down during a telephone conversation with Wulf, constitutes an ozone-depletion Rosetta Stone.
⁸²
It links Chapman's 1934 speech, Wulf, rocket fuel emissions, ozone-destroying reactions triggered by chlorine and bromine as catalysts, particulates, methane destruction, and an estimate that a minuscule amount of atomic bromine could cause immense harm (figure 7.8).

In the summer of 1962, Wexler accepted an invitation from the University of Maryland Space Research and Technology Institute to present a lecture titled “The Climate of Earth and Its Modifications” and might, under normal circumstances, have prepared his ideas on geoengineering and ozone destruction for publication. However, he was cut down in his prime by a sudden heart attack on August 11, 1962, during a working vacation at Woods Hole. The documents
relating to his career—from his early work at MIT, his work as liaison to the IAS meteorology project, his research into all sorts of new technologies, to his final speeches on ozone depletion and climate control—headed into the archives, probably not to be seen and certainly not to be reevaluated until today.

7.8 Harry Wexler's “Rosetta Stone” note, linking Sydney Chapman, Oliver Wulf, rocket fuel, and catalytic ozone-destroying reactions triggered by chlorine and bromine. (WEXLER PAPERS)

The well-known and well-documented supersonic transport (SST) and stratospheric-ozone-depletion issues date only to the 1970s and do not include Wexler's role. The idea that bromine and other halogens could destroy stratospheric ozone was published in 1974, while chlorofluorocarbon production expanded rapidly and dramatically after 1962.
⁸³
Had Wexler lived to publish his ideas, they would certainly have been noticed and could have led to a different outcome and perhaps an earlier coordinated response to the issue of stratospheric ozone depletion. Recently, I have been in correspondence with three notable ozone scientists about Wexler's early work: Nobel laureates Sherwood Rowland and Paul Crutzen and current National Academy of Sciences president Ralph Cicerone. They are uniformly interested and quite amazed by Wexler's insights and accomplishments.

Remarkable, too, is the fact that with all his sophistication and the leading roles he played in the development of computer modeling, satellite monitoring, and many, many other technical fields, Wexler still opened his 1962 lectures by quoting extensively from Zworykin's “Outline of Weather Proposal” (1945) and von Neumann's response to it. A colleague who heard Wexler's lecture in Boston wrote that climate engineering constituted “a delightful area of mental gymnastics. Let's hope the entire world is satisfied to play the game on this plane until the state of meteorological knowledge is truly adequate for big league experimentation.”
⁸⁴
Wexler replied, “I hope that before we get into large experimentation that not only will the state of meteorological knowledge be much more advanced than it is now, but also the state of our socio-political affairs as well.”
⁸⁵
Remember, it was not Paul Crutzen in 2006 but Harry Wexler about fifty years before who first claimed that climate control was now “respectable to talk about,” even if he considered it quite dangerous and undesirable.