Mapping the Critical Zone, Lecture by Alexandra Arènes, Westminster University – 21/22 March 2019 – Monass

Proposal:Presentation of a diagrammatic model for observatories of the Earth according to the Critical Zone view. 

Key words:model, Anthropocene, biogeochemical cycles, landscape disturbances

The Critical Zone is a term coined by geoscientists (hydrologists, soil scientists, geochemists, etc.) who collectively attempt to understand the Earth’s responses to climate change through the study of biogeochemical cycles. Unlike the globe, which offers a view from nowhere, the Critical Zone is located and corresponds to the thin layer of the planet where life has proliferated from the top of the canopy to the deep rocks below. It corresponds to an animated Earth, Gaia, as a result of the terraforming of living beings. However, according to scientists, this point of view is poorly represented. That is why we[1]have undertaken interdisciplinary work to build a new model, which was published last year[2].  The model is an experiment to think of a territory in terms of terrestrial cycles. It therefore aims to share a sensitivity to the Critical Zone with its complex processes, dynamics and phenomena, while reconceptualising its space. It gives more space to the description of the constituents of the soil, the ground that living things inhabit, while giving it more depth. First drawn on CZ Observatories, the model could be applied to other sites where the important challenge is to visualise a territory through cycles and no longer from the traditional grid system (longitude-latitude). Indeed, the Anthropocene asks us to rethink our tools and conceptual frameworks (Nature) to understand the impact of man-industry on the atmosphere, soil and rocks. Thus, the model could be applied to a range of different sites from industries to urban areas, including those whose climate is particularly sensitive to disturbances. For the monsoon symposium, I propose to present further researches on the Critical Zone, by visualising the water found there (rivers, groundwater, clouds).

[1]a sociologist and philosopher of science, Bruno Latour; a geochemist head of the French Critical Zone network, Jérôme Gaillardet (Institut de Physique du Globe de Paris); and myself, landscape architect and doctoral candidate.

[2]  “Giving Depth to the Surface – an Exercise in the Gaia-graphy of Critical Zones”, The Antropocene Review, 29 June, 2018. With Bruno Latour and Jérôme Gaillardet.