One does not need to go far in the public discourse surrounding climate change to be inundated with the mystique of number. In the United States, where viewers of Al Gore’s An Inconvenient Truth were treated to stunts of quantificatory pontification, just as in Singapore, where I teach climate change to nonspecialist undergraduates, the number work of graphs and charts has distinct techie vitality.
Drawing on my on-going research on the imaginative dimensions of carbon accounting, in this commentary I look toward key moments in the emergence of climate change science to identify why the numbers mystique holds such powerful sway over possibilities for thinking climate change. Part of the story must include the promises of ‘big data’ and sheer computational prowess of the late-20th century. But why are quantification and future-oriented mathematical speculation so essential to the scientific and the political dimensions of climate change?
Asking this question turns out to be a small part of a much larger question, first formulated in the late 19th century but which structures many aspects climate science and politics today. I trace here three genealogical moments.
Joseph Fourier created crucial mathematical techniques related to solving partial differential equations in the context of analyzing the empirical properties of heat transfer. The question that preoccupied his attention was what factors determined the temperature of the earth. Fourier’s work, mostly completed in the first decade of the 19th century but published in 1820s, poses the problem of Earth’s temperature in terms of comprehensive planetary thermodynamics at a time when it was just becoming possible for Europeans to conceive of the temporal contingency of human existence.
Historian of science Robert Friedman argues that Fourier demonstrated the success of positivist analysis along with the late-18th century French refusal of metaphysical speculation on first causes or essences. He quotes Condillac: “We do not see these causes, these natures, these essences; it would be in vain to attempt to show them to us.” But that metaphysical refusal is marked by a profound reliance on calculative speculation regarding experimental worlds. Consider this statement of Fourier’s methodological approach:
We have therefore determined the variable state of a globe, of a substance whose specific qualities we know by experiment, and which after being immersed for some time in a heated medium, is transported to a colder space. We have considered likewise the variable state of a sphere which, having been plunged successively and for some time in two or more media of different temperatures, should undergo a final cooling in a medium of constant temperature.
Such is his experimental and mathematical imagination of Earth’s temperature problem. One could find seeds of a science fiction here.
Fourier is commonly cited as the grandfather of modern climate science because he anticipates the insulating properties of the atmosphere, which allows visible radiation to pass more easily than infrared radiation reflected from Earth back toward space. That much is true—he relies on experimental measurements—but, as James Fleming shows, it exaggerates the continuity in conclusive scientific results.
It also neglects the activity of thinking manifest in a mathematical problem for which he could not give a satisfactory answer but which continued to be reformulated and reworked throughout the 19th century. What would be the temperature of an ideal blackbody the size of Earth, circling the Sun in its orbit? “Under this hypothesis of absolutely cold space, if such a thing is possible to conceive of, all effects of heat, such as we observe at the surface of the globe, would be due solely to the presence of the Sun. [… Without Earth’s atmosphere, the] surface of bodies would be exposed all of a sudden, at the beginning of night, to an infinitely intense cold”. That imaginative potential constitutes a generative curiosity, here manifest in conceiving of an exposed planet floating in space potentially bereft of the comforts of climate. Imagining theoretical planets most captures Fourier’s direct inheritance.
In fact, Fourier could not imagine that the insulation of the atmosphere would protect from such an intense cold, and theorized that interplanetary space could only be a little colder than the poles of the planets. Fourier was wrong about many things, but it was he who taught the strategy of mathematical speculation on what would become the question of what regulates Earth’s temperature.
In Svante Arrhenius’s work, Fourier’s speculation, combined with insight by Pouillet and Tyndall, could be formulated as a fundamental problem demanding explanation. Arrhenius quotes the results of research by American meteorologist Samuel Langley: “the temperature of the earth under direct sunshine, even though our atmosphere were present as now, would probably fall to -200deg. C if the atmosphere did not possess the quality of selective absorption” of heat performed by CO2. Arrhenius refutes Langley, but that question nonetheless demanded quantitative calculation of “the influence of Carbonic Acid in the Air upon the Temperature of the Ground,” as he puts it in the title of his famous essay.
Arrhenius’s essay is remarkable for its attempt to provide a quantitative, relatively comprehensive examination of whether Earth’s global climate, due to changes in the quantity of CO2 in the atmosphere, could vary enough to explain “genial or glacial epochs” in the geological record. The scientific problem was how to explain ice ages which, along with theories of evolution, had severely challenged assumptions about Earth’s age. Attempting to estimate global climate, he tabulated temperature and humidity records from around the world, recognizing the importance and difficulty of formulating such global numbers. He also attempts to account for crucial factors such as ice and cloud reflectivity and even feedbacks between CO2, ice reflectivity and water vapor. With the work of his colleague Högbom, he provides a provisional calculation of geological carbon cycles, including an estimate of “temporary” contributions from human activity, namely coal extraction. Industrialization had long precipitated an awareness of people as geological actors.
Most importantly for my argument, the results of his work take the form of estimates of temperature changes based on hypothetical quantitative variation in atmospheric carbon dioxide. What would be Earth’s temperature if CO2 levels were two-thirds or twice the current level? When debates surged a century later, arbitrated by the United Nations’ Intergovernmental Panel on Climate Change, on the climate sensitivity of the Earth to an increase of CO2, the question recapitulated exactly this quantitative form, ΔT2x, the temperature change due to a doubling of atmospheric carbon dioxide.
Tyndall, long before Charles Keeling and even before Arrhenius, demonstrated the heat trapping dimensions of fossil energy gases, and the modern statement of the problem of climate change as a risk known to and caused by human activity is commonly attributed to Callendar. What was not known, and what was essential to Keeling’s scientific endeavor beginning in the 1950s, was whether emissions from burning fossil energy in fact resulted in a rise in a global greenhouse gas emissions. It was more plausible that the oceans as the largest sink of carbon dioxide would simply absorb whatever additional CO2 humans put into the atmosphere.
In fact, nobody knew how to measure atmospheric carbon dioxide in any way that would be globally relevant. Keeling demonstrated that localized background CO2 fluctuations could be eliminated if measurements were taken from especially remote locations. The Mauna Loa Observatory, at an elevation of over 11,000 feet in the center of the Pacific Ocean, served as the location for the production of such a global number. After only the first two years of measurement, Charles Keeling demonstrated an increase of about 2/3 parts-per-million per year. That research has consistently proven one of the least controversial key elements to the overall scientific problem of establishing the anthropogenic basis of contemporary global warming.
Maintaining Fourier’s speculative perspective, Roger Revelle (with Hans Seuss), who had secured Keeling’s funding and to whom Keeling answered at Scripps Institution of Oceanography, argued that “human beings are now carrying out a large scale geophysical experiment [...]. Within a few centuries we are returning to the atmosphere and oceans the concentrated organic carbon stored in sedimentary rocks over hundreds of millions of years” (Revelle and Seuss, 1957, Carbon dioxide exchange between atmosphere and ocean and the question of an increase of atmospheric CO2 during the past decades. Tellus X). Arrhenius posed the scientific problem of climate change in terms of a hypothetical doubling of atmospheric carbon dioxide concentration; Keeling’s work ensured that the rise in concentration was much more than a neat way to state a scientific problem. That anthropogenic etiology of a radically changed biosphere has since defined the unity of climate change as a human problem.
Who cannot sense the excitement in Revelle and Seuss’s anticipation of the planetary stakes of the moment? “This experiment, if adequately documented, may yield a far-reaching insight into the processes determining weather and climate.” When one imagines scary apocalyptic futures fraught with uncertainty but which hinge on that single variable, the atmospheric concentration of greenhouse gases, one does so through these three modalities—speculation, quantification and anthropogenesis.
Yet the ways in which pop climate discourse repeats eschatology are less relevant. The focus on imaginative speculation materialized in durable form helps explain both the ways climate models work, oriented toward future extrapolation with an inherent problematic of uncertainty, and financial speculation for emissions reductions in the form of global carbon markets. We are neither repeating the temporal horizon of a secular apocalyptic imagination, nor simply quantifying and rationalizing nature. If apocalypse closes time by announcing the end if the world, climate science and climate politics both are oriented toward open futures in which it is possible—indeed, perhaps necessary—to reimagine contemporary forms of human living at a planetary scale.
Jerome Whitington is a research fellow at the Asia Research Institute, National University of Singapore.