The Potential Effects of Global Climate Change on the United States: Draft Report to Congress Printing Office in two volumes
State of the World 1988: A Worldwatch Institute Report on Progress Toward a Sustainable Society
A Matter of Degrees: The Potential for Controlling the Greenhouse Effect
For most Americans, last summer was one of the hottest on record. Some experts said the heat may have been a sign of what to expect from the “greenhouse effect”—the increased levels of carbon dioxide in the atmosphere as the result of burning fossil fuels. The carbon dioxide traps the sun’s infrared radiation close to the planet’s surface and causes the temperature to rise. Other experts said no: last summer’s heat was simply weather.
This debate is not new. In 1896 and 1908, the great Swedish scientist Svante Arrhenius published papers setting forth what we know now as the greenhouse hypothesis. He calculated that if enough coal and oil were burned to double the concentration of carbon dioxide that existed in the atmosphere before the Industrial Revolution, the temperature of the planet would increase between four and six degrees Celsius, or seven to ten degrees Fahrenheit. In the decades that followed, other researchers occasionally touched on his work. Almost fifty years ago, in 1939, G.S. Callender, a British meteorologist, speculated that a warming induced by carbon dioxide was already underway. But most scientists were otherwise occupied and, anyway, the prevailing view held that the oceans, which contain sixty times as much carbon dioxide as the atmosphere, would serve as a convenient dump, soaking up the gas as speedily as people could create it.
Then, in 1957, Roger Revelle and Hans Suess of the Scripps Institute of Oceanography in La Jolla, California, demonstrated that the upper layers of the ocean would not absorb carbon dioxide anywhere near as rapidly as had been assumed. This discovery may someday be remembered as defining the most important limit in an age of limits, the central awkward fact of a hot and constrained life. “Human beings are now carrying out a large-scale geophysical experiment of a kind that could not have happened in the past, nor be repeated in the future,” wrote Revelle and Suess. “The experiment,” they added with morbid understatement, “if adequately documented, may yield a far-reaching insight into processes determining weather and climate.”
The thirty years since have been spent compiling that adequate documentation—what quickly was dubbed the greenhouse theory became one of the main preoccupations of atmospheric science. The first task, since no one even knew for certain that carbon dioxide was increasing, was to measure its concentration in the atmosphere. In 1958, as a part of the International Geophysical Year, a Scripps scientist established a monitoring station 11,150 feet up the side of Mauna Loa in Hawaii, high enough above civilization for uncontaminated readings. In fairly short order, the data revealed a clear pattern: there was an annual fluctuation, with carbon dioxide decreasing in the springtime as plants wake up and take in carbon dioxide through photosynthesis, and increasing in the fall as leaves die, but this fluctuation peaked at a steadily higher level each year. Carbon dioxide was marching upward—concentrations in the atmosphere were rising at a rate of about one …