Michel Armatte

Climate change: scenarios and integrated modelling

Abstract This paper examines the genealogy of long-term studies in economics and its mobilisation in climate change research. Long-term studies differ from short-term forecasting and planning not only in their length of foresight but also by taking account of strategic and policy objectives. These strategic considerations are not within the scope of longue durée historians, nor are they integrated into econometrics or national accounting practices of forecasting. Only planning and prospective analysis include this dimension. The method of scenarios is then at the core of long-term studies and prospective approaches. The conception and use of scenarios is reviewed through various national and international studies since the 1970s – DATAR, OCDE, CPB and, finally, the IPCC scenarios report – as well as their implementation in integrated assessment models (IMAGE, for example).

Introduction to the work of Alain Desrosières: the history and sociology of quantification

In this paper we are describing our partnership in research on history of statistics with Alain Desrosieres who pass away in 2013. Then we are tracing his intellectualitinerary : training at Ecole Polytechnique and National School of Statistics, meeting with Pierre Bourdieu, first studies on History in Statistics in 1976 and on ocupational and social categrization with Thevenot in the 1980’s, and publication of his major book of 1993 – la politique des grands nombres, with the new resource he found besaide sciences studies school and Bielefeld works on the probabilistic Revolution. We are then debating of some problems he assessed like the gap between statistics as tool of proof and as mean of government, between realist or constructivist approaches of statistics, or again the differences between measurement in natural and social sciences, with the prominent part of conventions. After 2000 he launched an ambitious program of Sociology of quantification which concerned not only statistics but also comptability.