Have we really just met the planet? The humanities and social sciences have tended to embrace ecological and climate issues, the Anthropocene and the Earth system sciences, by dramatising the novelty of environmental knowledge and reflexes about what 'we' are doing to the planet. More than a simple analytical contrast between global and planetary thinking, key scholars have framed this polarity in a progressive, time-oriented narrative of a recent turn from an obscure and narrow 'before' to a more environmentally conscious 'now'.

But this "once was blind but now can see" thesis does not hold, as many recent works in history of science and technology as well as in environmental history teach us. Time has come to craft new conceptual frameworks, that enables to investigate both the age, the transformations and the historicity of the planetary environmental reflexivities at different times over the last 500 years (and to pluralize the issue of “planetarity” beyond western science and western culture).  Analog to François Hartog’s notion of “regimes of historicity”, we can think in terms of changing and diverse “regimes of planetarity”. The talk will present the concept of regimes of planetarity as a way of historicizing the way in which societies have organized and thought about their relationship to the planet, its beings and its functioning, at the crossroads of material dynamics (world-ecologies), knowledge dynamics (environmental reflexivities) and (geo)political arrangements (geopowers) (Bonneuil, 2020).

To put this analytical framework to the test, we'll explore how, by 1864-1918, Western imperial elites and expert communities approached various environmental alerts of great spatial and/or temporal scope. How did they create the “planetary” by aggregating figures and maps, looking to Mars or the geological past in order to talk about their future?  If many “planetary” alerts were present, we will finally examine the “solutions” put forward by these expert communities, imbued with coloniality and technological solutionism: the invocation of future generations (but which ones?), the plantation as a sustainable use of tropical lands, fish farming, acclimatization and bio-prospection to make up for the extinction of species and varieties, the superior right of white man to develop the planet and say what its correct use is. The turn of the 19th and 20th centuries thus saw the rise to power of an imperial regime of planetarity, from which we still inherit elements of coloniality in current discussions on the global environment and the Anthropocene.