ESHS/HSS Annual Meeting

Multiplicity and the making of “simple and unambiguous”: The Keeling curve of rising atmospheric carbon

• In Event: Reappraising Three Iconic Images in the History of Science

English Abstract

This paper tracks the cultural creation and commodification of the “Keeling curve,” a widely distributed graph of rising atmospheric carbon dioxide and an icon of global change. Much historiography credits the Keeling curve with bringing scientific and public attention to greenhouse warming beginning around 1960, spurring an era of global-warming research and serving as the “Silent Spring of climate change” (Flannery 2005). I argue instead that the Keeling curve—as a visually distinctive chart by that name—emerged in the 1980s as a product of scientific and social developments it is now supposed to have caused. In the 1960s and 1970s, most graphs of atmospheric CO2 data were neither visually remarkable nor readily identifiable absent a label. Even when the data appeared before politicians in discussions of climate and energy, the most common display hardly resembled the oscillating upward trend promulgated today. In the 1980s, casual acts of reference by geochemists using (and graphing) CO2 data to calibrate carbon-cycle models catalyzed a semantic consolidation of diverse depictions of “Keeling’s observations” into “the Keeling curve”--a singular notional object, initially independent of any display, which scientists began to uphold as both warrant and explanation for climate concern. It was a journalist seeking to convey certainty and inspire action who first portrayed the rising CO2 index as exclusively iconic, when he initiated the now-common but then-ironic trend of depicting the trend alone—absent the information that had given rise to the curve by making the underlying data useful. Tracing this trend into the 21st century, onto neckties and lapel pins as well as the wall of the National Academy of Sciences, I consider how reification of the CO2-rise representation has underpinned teleological appraisals of the image’s supposed historical role, as a transformation device that was somehow always and already “simple and unambiguous” (Nisbett 2007).

Author

• Madison Renner, Harvard University