The history of climate research in the 20th century has been characterised by a crucial shift from a geography-oriented, two-dimensional approach towards a physics-based, three-dimensional concept of climate. In the 1930s, the introduction of new technology, such as radiosondes, enabled climatologists to investigate the high atmosphere, which had previously been out of reach. This “conquest of the third dimension” challenged the surface-oriented, geographical notion of climate patterns and opened up climatology to a three-dimensional approach, which deeply changed the character of (...) climate research. Two decades later, by drilling deep into polar glaciers and using the downward vertical dimension as an archive of the earth's history, ice core scientists began to reconstruct past climates layer by layer. The data retrieved in deep glacial layers contributed crucially to a temporal expansion of climate history far beyond human timescales. However, the inaccessibility of glaciers and the practical challenges of bringing fragile fragments of ice into transnational networks of scientific exchange meant that this vertical extension of climate knowledge production proceeded through a range of new scientific practices, and was shaped by new forms of international collaboration. Furthermore, this vertical approach to glaciers also asked for a new understanding of glacier volume. Drawing on archival and printed sources, I argue that ice core research represented a second discovery of the third dimension, this time downwards into the depth of the earth's surface, but again with decisive consequences for the research practice, for collaboration politics, and for understandings of climate, spatially as well as temporally. (shrink)

It is important to have an adequate model of uncertainty, since decisions must be made before the uncertainty can be resolved. For instance, flood defenses must be designed before we know the future distribution of flood events. It is standardly assumed that probability theory offers the best model of uncertain information. I think there are reasons to be sceptical of this claim. I criticise some arguments for the claim that probability theory is the only adequate model of uncertainty. In particular (...) I critique Dutch book arguments, representation theorems, and accuracy based arguments. Then I put forward my preferred model: imprecise probabilities. These are sets of probability measures. I offer several motivations for this model of uncertain belief, and suggest a number of interpretations of the framework. I also defend the model against some criticisms, including the so-called problem of dilation. I apply this framework to decision problems in the abstract. I discuss some decision rules from the literature including Levi’s E-admissibility and the more permissive rule favoured by Walley, among others. I then point towards some applications to climate decisions. My conclusions are largely negative: decision making under such severe uncertainty is inevitably difficult. I finish with a case study of scientific uncertainty. Climate modellers attempt to offer probabilistic forecasts of future climate change. There is reason to be sceptical that the model probabilities offered really do reflect the chances of future climate change, at least at regional scales and long lead times. Indeed, scientific uncertainty is multi-dimensional, and difficult to quantify. I argue that probability theory is not an adequate representation of the kinds of severe uncertainty that arise in some areas in science. I claim that this requires that we look for a better framework for modelling uncertainty. (shrink)

How climate models came to gain and exercise epistemic authority has been a key concern of recent climate change historiography. Using newly released archival materials and recently conducted interviews with key actors, we reconstruct negotiations between UK climate scientists and policymakers which led to the opening of the Hadley Centre for Climate Prediction and Research in 1990. We historicize earlier arguments about the unique institutional culture of the Hadley Centre, and link this culture to broader characteristics of UK regulatory practice (...) and environmental politics. A product of a particular time and place, the Hadley Centre was shaped not just by scientific ambition, but by a Conservative governmental preference for ‘sound science’ and high evidential standards in environmental policymaking. Civil servants sought a prediction programme which would appeal to such sensibilities, with transient and regional climate simulation techniques seemingly offering both scientific prestige and persuasive power. Beyond the national level, we also offer new insights into the early role of the Intergovernmental Panel on Climate Change and an evolving international political context in the shaping of scientific practices and institutions. (shrink)