How is it that something so complex—and indeed so abstract, something that is inferred rather than touched—could come to so dominate the future of energy and how people live, and become one of the main issues in the politics among nations ? That is the story that follows here.
It is striking to see how glaciers and their advance and retreat have been the constant, the leitmotiv, indeed, even central actors, in the study of climate change from the very beginning of the scientific investigations all the way up to the contemporary images of blocks of melting Antarctic ice tumbling into sea. Today glaciers serve as Cassandras for climate. But they are also living history—time machines that enable us to be in the present and yet, at the same moment, go back 20,000 years into the past.
A series of related puzzles converged in the late eighteenth and nineteenth centuries to provide the intellectual origins of thinking on climate change. One was the determinants of the earth’s temperature. Why, to put it simply, was life possible on earth? That is, why did the planet not become burningly hot when the sun shone and then freezingly cold at night? Another was the suspicion—and the fear—that the current era of moderate temperatures had been preceded by something different and more extreme, something that haunted thinking about mankind’s past: what came to be known as the Ice Age.
These puzzles led to two arresting questions: What could have made the climate change? And could glaciers return, like some immense, fearsome primordial beasts, crushing everything in their paths, smashing and obliterating human civilization as they advanced?
The story begins in the Swiss Alps and its glaciers, more than half a century before John Tyndall first laid eyes upon them.
THE ALPINE “HOT BOX”
Horace Bénédict de Saussure was a scientist, a professor at the Academy of Geneva. He was also an Alpinist, a mountain climber and explorer who devoted his life to trying to understand the natural world in Switzerland’s high peaks. To describe his vocation in his classic work, Voyages dans les Alpes, he invented the word “geology.” Saussure was fascinated by heat and altitude, and built devices to measure temperatures at the tops of mountains and the bottoms of lakes.4
But a question troubled Saussure as he traipsed through the Swiss mountains. Why, he asked, did not all the earth’s heat escape into space at night? To try to find an answer, he built in the 1770s what became known as his “hot box”—sort of mini greenhouse. The sides and bottom were covered with darkened cork. The top was glass. As heat and light flowed into the box, it was trapped, and the temperature inside would rise. Perhaps, he mused, the atmosphere did the same thing as the glass. Perhaps the atmosphere was a lid over the earth’s surface, a giant greenhouse, letting the light in but retaining some of the heat, keeping the earth warm even when the sun had disappeared from the sky.
The French mathematician Joseph Fourier—a friend of Napoléon’s and a sometime governor of Egypt—was fascinated by the experiments of Saussure, whom he admiringly described as “the celebrated voyager.” Fourier, who devoted much research to heat flows, was convinced that Saussure was right. The atmosphere, Fourier thought, had to function as some sort of top or lid, retaining heat. Otherwise, the earth’s temperature at night would be well below freezing.
But how to prove it? In the 1820s Fourier set out to do the mathematics. But the work was daunting and extremely inexact, and his inability to work out the calculations left him deeply frustrated. “It is difficult to know up to what point the atmosphere influences the average temperature of the globe,” he lamented, for he could find “no regular mathematical theory” to explain it. With that, he figuratively threw up his hands, leaving the problem to others.5
Over the decades, a few other scientists, harking back to Saussure and Fourier, and especially to Saussure’s hot box, began to speak about a “hot-house,” or “greenhouse,” effect as a metaphor to describe how the atmosphere traps heat. But how exactly did it work? And why?
“GREAT SHEETS OF ICE”
The Swiss scientist Louis Agassiz was also obsessed with glaciers—indeed so obsessed that he put aside his research on fossils of extinct fish in order to probe the workings of glaciers. He even built a hut on the Aar glacier and moved into it so that he might more closely monitor the glacier’s movement.
In 1837, more than a decade before John Tyndall first caught sight of a glacier, Agassiz propounded a revolutionary, even shocking idea. There had once been something before the present age, he declared. That “before” was an ice age, when much of Europe must have been covered by massive glaciers, “great sheets of ice resembling those now in Greenland.” That was an age, he said, when a “Siberian Winter” gripped the world throughout the year, a time when “death enveloped all nature in a shroud.”
The ice, Agassiz maintained, came about due to a sudden, mysterious drop in temperature that was part of a cyclical pattern stretching back to the beginning of earth’s history. As the glaciers had retreated to the north, they had left behind in their wake the valleys and mountains and gorges and lakes and fjords and boulders and gravel that documented their movement.
Agassiz’s bold assertion was met with great skepticism. One colleague advised him, for his own good, to give up on glaciers and instead stick to his “beloved fossil fishes.”
Agassiz would not be swayed. His continuing research provided further evidence on the movement of glaciers, or what he called “God’s great plough.” He later migrated to the United States, where he became a professor at Harvard University. He organized an expedition to the Great Lakes that demonstrated that they had been sculpted into the earth’s surface by the advance and retreat of glaciers—yet more evidence of an ice age. By proving that the earth had lived through different ages in terms of temperature, Agassiz was the real inventor of the idea of climate.6
THE ATMOSPHERE: “AS A DAM BUILT ACROSS A RIVER”
John Tyndall built his own research on the work of these predecessors. His keen interest in the migration of glaciers across Europe led him to seek to understand whether and how the atmosphere could trap heat. If he could make sense of that, he could begin to understand how the climate could change, a process that was embodied in the glaciers that obsessed him.
To find the answer, Tyndall built a new machine in his basement laboratory in the Royal Institution on Albemarle Street in London. This was his spectrophotometer, a device that enabled him to measure whether gases could trap heat and light. If the gases were transparent, they would not trap heat, and he would have to find some other explanation. He first experimented with the most plentiful atmospheric gases, nitrogen and oxygen. To his disappointment, they were transparent, and the light passed right through them.
What else could he test? The answer was right there in his laboratory—coal gas—otherwise known as town gas. This was a carbon-bearing gas, primarily methane made by heating coal, that was pumped into his laboratory by the local London lighting company to burn in order to provide illumination—pre-electricity. When Tyndall put the coal gas into the spectrophotometer, he found that the gas, though invisible to the eye, was opaque to light; it darkened. Here was his proof. It was trapping infrared light. He then tried water and carbon dioxide. They too were opaque. That meant that they too trapped heat.
By this point, Tyndall was close to collapse from continual ten-hour days in the laboratory and from his inhalation of fumes—of “gases not natural even to the atmosphere of London.” But that did not matter. He was elated. “Experimented all day,” he wrote in his journal on May 18, 1859, adding joyously, “The subject is completely in my hands!” Just three weeks later, he delivered a public lecture at the Royal Institution—with Prince Albert, the Prince Consort of Queen Victoria, in the chair—demonstrating and explaining his discovery and its significance. There on Albemarle Street, just off Piccadilly, was “the first public, experimentally based account” of the greenhouse effect.7
“As a dam built across a river causes a local deepening of the stream, so our atmosphere, thrown
as a barrier across the terrestrial (infrared) rays, produces a local heightening of the temperature at the Earth’s surface,” said Tyndall. “Without the atmosphere, you would assuredly destroy every plant capable of being destroyed by a freezing temperature.... The atmosphere admits of the entrance of the solar heat, but checks its exit; the result is a tendency to accumulate heat at the surface of the planet.”
What Tyndall had done in his basement laboratory was to provide the explanation for the greenhouse effect, for how climate worked, and for how, in his words, “every variation” of the constituents of the atmosphere “must produce a change of climate.” He gave particular credit to Saussure and Fourier. Here also was a confirmation for Louis Agassiz’s theory of the Ice Age. For variations in the balance of gases in the atmosphere “may have produced all the mutations of climate which the researches of geologists reveal.”
Tyndall went on to make other important contributions to science and gained great renown. Until late in life, he would also regularly return to Switzerland to take in the glaciers and climb the peaks. After a life as a mountaineer, undertaking many dangerous and daring mountain expeditions, including a number of near fatal accidents, Tyndall died in 1893, at age 73, under more prosaic circumstances. His wife had accidentally administered an overdose of sleep nostrum to relieve his intolerable insomnia. As he slipped away, he murmured, “My poor darling, you have killed your John.”8
ARRHENIUS: THE GREAT BENEFIT OF A WARMING CLIMATE
The year after Tyndall’s death, in 1894, a Swedish chemist named Svante Arrhenius picked up the story. Arrhenius was curious as to what effects increasing or decreasing levels of carbon dioxide—or carbonic acid, as it was called at the time—would have on the climate. He too wanted to weigh in on the mechanisms of the ice ages, the advance and retreat of glaciers, and what he called “some points in geological climatology.”
Arrhenius’s own academic career was not smooth. He had difficulty getting his Ph.D. accepted at the University of Uppsala. But now, more established in Stockholm, he found his interest in carbon and the ice age stoked in a scientific seminar that met on Saturdays. Melancholic over his divorce and loss of custody of his son, and with much time on his hands, Arrehenius threw himself into month after month of tedious calculations, sometimes working 14 hours a day, proceeding latitude by latitude, trying by hand to calculate the effects of changes in carbon.
After a year, Arrhenius had the results. Invoking Tyndall and Fourier, he said, “A great deal has been written on the influence of the absorption of the atmosphere upon the climate.” His calculations showed that cutting atmospheric carbon in half would lower the world’s temperature by about four to five degrees centigrade. Additional work indicated that a doubling of carbon dioxide would increase temperatures by five to six degrees centigrade. Arrhenius did not have the benefit of supercomputers and advanced computation; he arrived at the above prediction after a tediously huge number of calculations by hand. Nonetheless, his results are in the range of contemporary models.9
Even if he was the first to predict, at least to some degree, global warming, Arrhenius was certainly not worried about the possibility. He thought it would take 3,000 years for CO2 to double in the atmosphere, and in any event that would be a good thing. He later mused that the increased CO2 concentrations would not only prevent a new ice age but would actively allow mankind to “enjoy ages with more equable and better climates,” especially in “the colder regions of the earth,” and that would “bring forth much more abundant crops than at present for the benefit of rapidly propagating mankind.” And that did not sound at all bad to a lonely Swedish chemist who knew all too well what it was like to live, year after year, through long, dark, cold winters.10
“My grandfather rang a bell, indeed, and people became extremely interested in it at that time,” said his grandson Gustaf Arrhenius, himself a distinguished chemist. “There was a great flurry of interest in it, but not because of the menace, but because it would be so great. He felt that it would be marvelous to have an improved climate in the ‘northern climes.’ And, in addition, the carbon dioxide would stimulate growth of crops—they would grow better. So he and the people at the time were only sad that in his calculations it would take [so long] to have the marked effect.”11
In time, however, attention drifted away from the subject of carbon and climate. Arrhenius himself turned to a number of other topics. In 1903 he was awarded the Nobel Prize in chemistry—not bad for someone whose Ph.D., which initiated the research for which he won the prize, was almost rejected.
In the decades that followed, the world became much more industrialized. Coal was king, both for electric generation and factories, which meant more “carbonic acid”—CO2—going into the air. But there was little attention to climate.
In the Depression years of the early 1930s, drought struck the American Midwest. Poor cultivation techniques had left the topsoil loose and exposed, and winds swept it up into great dust storms, sometimes so intense as to block out the sun, leaving the land barren. The economic devastation drove hundreds of thousands of farm families to pack their belongings on their Model Ts, and, like the fictional Joad family in John Steinbeck’s Grapes of Wrath, living in a “dust-blanketed land,” take to the roads and head to California as migrant refugees from the Dust Bowl. 12
But those droughts were “weather,” not “climate.” No one talked about climate for decades. Or almost no one.
THE EFFECT OF GUY CALLENDAR: CALCULATING CARBON
In 1938 an amateur meteorologist stood up to deliver a paper to the Royal Meteorological Society in London. Guy Stewart Callendar was not a professional scientist, but rather a steam engineer. The paper he was about to present would restate Arrhenius’s argument with new documentation. Callendar began by admitting that the CO2 theory had had a “chequered history.” But not for him. He was obsessed with carbon dioxide and its impact on climate; he spent all his spare time collecting and analyzing data on weather patterns and carbon emissions. Amateur though he was, he had more systematically and fully collected the data than anyone else. His work bore out Arrhenius. The results seemed to show that CO2 was indeed increasing in the atmosphere and that would lead to a change in the climate—more specifically, global warming. 13
While Callendar found this obsessively interesting, he, like Arrhenius, was hardly worried. He too thought this would make for a better, more pleasant world—“beneficial to mankind”—providing, among other things, a boon for agriculture. And there was a great bonus. “The return of the deadly glaciers should be delayed indefinitely.” 14
But Callendar was an amateur, and the professionals in attendance that night at the Royal Meteorological Society did not take him very seriously. After all, he was a steam engineer.
Yet what Callendar described—the role of CO2 in climate change—eventually became known as the Callendar Effect. “His claims rescued the idea of global warming from obscurity and thrust it into the marketplace of ideas,” wrote one historian. But it was only a temporary recovery. For over a number of years thereafter the idea was roundly dismissed. In 1951 a prominent climatologist observed that the CO2 theory of climate change “was never widely accepted and was abandoned.” No one seemed to take it very seriously.15
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THE AGE OF DISCOVERY
Quite late in his life, Roger Revelle ruminated on his career in science.
“I’m not a very good scientist,” he said. But then he added, “I’ve got a lot of imagination.” One of the things that had captured his imagination, and held it for many decades, was carbon dioxide. And that preoccupation would turn out to be profoundly important not only for the understanding of climate, but also for the future of energy.
Revelle was, however, more than a little self-deprecating. For he had made the remark in conjunction with being awarded the National Science Medal, the country’s highest scientific honor, by President George H. W. Bush in 1990 in recognition of his far-reaching impact on science
.
In addition to being a scientist, Revelle, a man of imposing stature and dominating personality, was also a naturalist, an explorer of the seas, an institution builder, and one of the inventors of the connection between basic research and government policy. He came equipped to his subjects with considerable curiosity abetted by what academic opponents derided as “impetuous enthusiasm and crusading spirit.”1
In presenting the award to Revelle, President George H. W. Bush singled out his “work in carbon dioxide and climate modification” as the first of his accomplishments, ahead of his other achievements in “oceanographic exploration presaging plate tectonics, the biological effects of radiation in the marine environment, and studies of human population growth and food supply.”
Revelle had launched his career with research expeditions into the unexplored deep waters of the Pacific. But, as it turned out, what he had set in motion in terms of research into carbon’s role in the atmosphere and man’s impact on that balance would also be of great—indeed, monumental—importance. And that grand scientific expedition, unfolding over decades, enlisting ever-greater computing power, traversing oceans and glaciers, mountaintops, the depths of the seas, and even outer space, is what put climate change and the heretofore unknown subject of global warming firmly on the political map.
Or, as Revelle put it, explaining the reasons he had received the National Science Medal, “I got it for being the grandfather of the greenhouse effect.”2
Revelle started off to be a geologist, but a fear of heights made him shy away from climbing up the sides of mountains, and he turned instead to the study of the depths of the oceans. He was one of the people who transformed oceanography from a game for wealthy amateurs into a major science. During World War II he was the U.S. Navy’s chief oceanographer. After the war he was one of the leaders in creating the Office of Naval Research, which supported much of the basic postwar scientific research in American universities—funding almost anything “that could, by the most extreme stretch of the imagination, serve national defense interests.” The Office of Naval Research, with Revelle’s prodding, was also the progenitor for what became the National Science Foundation. Revelle transformed Scripps Institution of Oceanography in La Jolla, California, north of San Diego, from a small research outpost, with one boat, into a formidable research institution, armed with a flotilla of ships that continually pushed out the frontiers of oceanic knowledge. He also made it into a “top carbon-cycle research center in the U.S.”3
The Quest: Energy, Security, and the Remaking of the Modern World Page 49
