Gardens into Deserts

http://www.thegreatonwardpress.com/9980/05/index19article4.html

Boulder, [Colorado,] was a good spot for the conference on “Causes of Climate Change” that convened there in August 1965. The meeting was scarcely noticed by most scientists at the time, but in retrospect it was a turning point.

The organizers had deliberately brought together experts in everything from volcanoes to sunspots, presided over by the oceanographer Roger Revelle. Lectures and roundtable discussions were full of spirited debate as rival theories clashed, and Revelle needed all his exceptional leadership skills to keep meeting on track. The conference was convened mainly to discuss the many rival explanations of the ice ages in the comfortable traditional mode. Instead, it exploded with new ideas that pointed to a novel and foreboding way of looking at the future of climate. The planet’s climate, the scientists agreed, could not be treated in the old fashion like some simple mechanism that kept itself stable. It was a complex system, precariously balanced. The system showed a dangerous potential for dramatic change, on its own or under human technological intervention, and quicker than anyone had supposed.

At the Boulder meeting not only the climate, but ways of studying it, appeared in a new light. The familiar unchanging climatology of statistical compilations held no appeal for these scientists. They were trying to build up their knowledge from solid mathematics and physics, aided by new techniques drawing on fields from microbiology to nuclear chemistry. But science alone could not explain the deep shift in views about one of the fundamental components of human experience. Events had been altering the thinking of everyone in modern society.

Is human technology a force of geophysical scope, capable of affecting the entire globe? Surely it is not, thought most people in 1940. Surely it is, thought most in 1965. The reversal was not because of any changes in what scientists knew about global warming. The public’s rising concern for human impacts came from more visible connections between technology and atmosphere. One of these was a growing awareness of the dangers of atmospheric pollution. In the 1930s, citizens had been happy to see smoke rising from factories: dirty skies meant jobs. But in the 1950s, as the economy soared and life expectancy lengthened in industrialized countries, a historic shift began, from worries about poverty to worries about chronic health conditions. Doctors were learning that air pollution was mortally dangerous for some people. Meanwhile, in addition to smoke from coal-burning factories came exhaust from the rapidly proliferating automobiles. A “killer smog” that smothered London in 1953 demonstrated that the stuff we put into the air could actually slay several thousand people in a few days.

The public’s attention was also drawn to the air by the news of attempts to make rain by “seeding” clouds. Scientists openly speculated about the technical tricks, such as spreading a cloud of particles at a selected level in the atmosphere to interfere with solar radiation. Journalists and science-fiction writers suggested that with such techniques, the Russians might someday inflict deadly blizzards on the United States. It had become plausible that by putting materials into the air humans could alter climate on the largest scale, perhaps not for the better.

The biggest stimulus to changes in thinking was the astonishing advent of nuclear energy. Suddenly nothing seemed beyond human power. To many people the news of a limitless energy source was hopeful, even utopian. Among many other wonders, experts speculated about salvoes of atomic bombs to control weather patterns, bringing rain exactly where it was needed. At the same time, scientists warned that a nuclear war could destroy civilization. Widely seen movies and novels pictured the extinction of all life by radioactive fallout, carried around the world on the winds after a nuclear war.

By the late 1950s utopian hopes about technology began to dissolve as the nuclear arms race accelerated. Rising fears found a voice in shrill public debates and mass demonstrations against nuclear weapons tests. Exquisitely sensitive instruments could detect radioactive fallout from test explosions half a world away—the first recognized form of global atmospheric pollution. Then in 1962 Rachel Carson published Silent Spring, warning that pesticides such as DDT and other chemical pollution, drifting around the world much like fallout, could endanger living creatures not just in the neighborhood of the polluter, but everywhere. Feelings of dread multiplied: whether or not technology would turn deserts into gardens, it could demonstrably turn gardens into deserts!

… The new threats awoke images and feelings that most people had scarcely experienced outside their dreams and nightmares. Humans were introducing unnatural technologies, meddling with the very winds and rain, spreading pollution everywhere.

… Revelle took the lead in suggesting that trouble might lie ahead. As soon as he calculated that a rise in the CO₂ level was likely, Revelle took pains to talk about global warming with science journalists and government officials. Noting that climate had changed abruptly in the past, perhaps bringing the downfall of entire civilizations in the ancient world, he warned that the CO₂ greenhouse effect might turn Southern California and Texas into “real deserts.” Testifying to Congress in 1956 and 1957, he was one of the first to use a new and potent metaphor: “The Earth itself is a spaceship,” he said. We had better keep an eye on its air control system.

— Spencer R. Weart,
The Discovery of Global Warming
(New Histories of Science, Technology, and Medicine),
Chapter 3 – A Delicate System