ESHS/HSS Annual Meeting

Picking Proxies in the Making of Global Climate Histories

• In Event: Making Global Temperature Across Land, Ice and Oceans

English Abstract

This paper connects three moments in the history of foraminifera as a climate proxy to explore how in different periods different scientific communities—natural historians, petroleum geologists, paleoclimatologists—linked diverse aspects of these unicellular marine creatures to build significant arguments about the long-term history of climate. One aim will be to show that forams were used variously to make arguments at different scales (local, oceanic, hemispheric and global) and about diverse climatic indices such as surface temperature and sea level. Yet if climate was always multifaceted, tracing how these arguments were represented in different periods will underline the significance of understanding the very different ways in which climate could be rendered global; and help show why it matters who tells the history of climate, when they do so, and for whom.
In the 1870s studies of the life cycle of foraminifera by Challenger scientists helped resolve puzzling questions about undersea landscapes and extended the ambit of climate into vertical depths, contributing to discussions about the formation of ‘modern chalk’ and the argument that the sea itself had climates. In the 1920s, petroleum firms pioneered a new form of micropaleontology in laboratory initiatives led by women, using forams to discern horizons in oilfield drill records. From the 1950s through 1970s Emilio Cesare and Nick Shackleton used forams picked from ocean sediment cores to tell new histories of the ice ages that shifted emphasis from sea temperature to water composition, ice volume and sea level. But if climate was importantly multiple in these ways, focusing on key papers in the 1970s will help show how picking species and identifying patterns within a core and across oceans could also lead to arguments on a hemispheric scale: one of several different means by which climate histories could be rendered global, even planetary. Examining further how these histories were figured and described will also reveal significant features of the changing valence of global arguments and different climate indices, and underline a critical tension in the way the IPCC moved between instrumental and other records in representing a range of different global temperature histories in 1990.

Author

• Richard Staley