OZCAR: French network of Critical Zone Observatories exploring the human's habitat

International audienceOZCAR (Critical Zone Observatories - Application and Research) is a national Research Infrastructure dedicated to providing an integrated understanding of the Earth's surface processes ranging from the subsurface to the lower atmosphere and from high mountains to coastal areas. It includes over 100 highly instrumented sites distributed among 21 observatories for long-term measurements of biological, chemical and physical parameters of groundwater, river water, glaciers, soils, and wetlands in France and overseas. Based on long-term observations at the landscape scale, OZCAR sites address specific environmental question of local societal relevance but all share the same overarching goal of better predicting the response of the Critical Zone to perturbations across a range of timescales. Diversity of OZCAR observation sites allows exploring laterally and vertically all compartments of the CZ from mountains to costal areas. This enables data acquisition on water, soils, agricultural practices and exchanges with the atmosphere. Thus, OZCAR proposes a great variety of models that ultimately will help reproducing observations and predict the evolution of the CZ. Through its wealth of environmental data portal and modelling platerforms, OZCAR aims at advising policy makers and stakeholers on the water, soil, and biodiversity resource. Recently, OZCAR integrated together with the French LTSER network (Zones Ateliers) the pan-European eLTER-ESFRI project

OZCAR : The French Network of Critical Zone Observatories

[Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU [ADD1_IRSTEA]Hydrosystèmes et risques naturels [Departement_IRSTEA]Eaux [TR1_IRSTEA]ARCEAU [ADD1_IRSTEA]Hydrosystèmes et risques naturelsSpecial Section: Hydrological ObservatoriesInternational audienceThe French critical zone initiative, called OZCAR (Observatoires de la Zone Critique-Application et Recherche or Critical Zone Observatories-Application and Research) is a National Research Infrastructure (RI). OZCAR-RI is a network of instrumented sites, bringing together 21 pre-existing research observatories monitoring different compartments of the zone situated between "the rock and the sky," the Earth's skin or critical zone (CZ), over the long term. These observatories are regionally based and have specific initial scientific questions, monitoring strategies, databases, and modeling activities. The diversity of OZCAR-RI observatories and sites is well representative of the heterogeneity of the CZ and of the scientific communities studying it. Despite this diversity, all OZCAR-RI sites share a main overarching mandate, which is to monitor, understand, and predict ("earthcast") the fluxes of water and matter of the Earth's near surface and how they will change in response to the "new climatic regime." The vision for OZCAR strategic development aims at designing an open infrastructure, building a national CZ community able to share a systemic representation of the CZ , and educating a new generation of scientists more apt to tackle the wicked problem of the Anthropocene. OZCAR articulates around: (i) a set of common scientific questions and cross-cutting scientific activities using the wealth of OZCAR-RI observatories, (ii) an ambitious instrumental development program, and (iii) a better interaction between data and models to integrate the different time and spatial scales. Internationally, OZCAR-RI aims at strengthening the CZ community by providing a model of organization for pre-existing observatories and by offering CZ instrumented sites. OZCAR is one of two French mirrors of the European Strategy Forum on Research Infrastructure (eLTER-ESFRI) project