Ozczo: the Australian critical zone network: quantifying impacts of climate change from bedrock to canopy

Australia, the driest inhabited continent, has no shortage of water issues. It also has some of the oldest and most intensively weathered and nutrient-deficient land surfaces on Earth. As a consequence, the soils and regolith are most often deep (much deeper than 1 m) and large stores of carbon are contained therein. We have little understanding of the dynamics and quantity and characteristics of this carbon. With climatic change and a near future that is expected to be dominated by progressively warmer temperatures, increasing water deficits, increased aridity, soil salinisation and ecological change, we need to predict and quantify impacts on ecosystems (and agricultural production), and on hydrological and biogeochemical cycles and lithospheric and atmospheric processes (e.g., water resources, feedbacks from soil, vadose zones and aquifers on carbon and other greenhouse gas exchanges). To address these knowledge gaps, we need comprehensive and continual observational data from bedrock to vegetation canopy and near-surface atmosphere from diverse environments across the continent. To this end we are establishing the foundations of the Australian Critical Zone Observatory network, OzCZO, which initially will consist of five CZOs (Critical Zone Observatories) covering four Australian states. The CZO are designed for advanced studies of hydrology and biogeochemical processes and elemental/isotope fluxes within near-surface reservoirs, including soils, water and vegetation. In this talk we will present the capabilities of these state-of-the-art observatories, some specific characteristics (geological/ hydrological/ climatic/ ecological) of each site, and some examples of early data collected. Finally, we will outline research questions that could be answered collaboratively using the OzCZO network.