Constraining the response of continental-scale groundwater flow to climate change
Plain Language Summary
Groundwater is one of Australia’s most vital resources, yet understanding how it flows through deep underground aquifer systems — especially over large distances and long timescales — remains a major challenge. This study develops a new computational framework to model groundwater flow at the continental scale, capturing both the broad flow patterns from inland to coast and the intricate local pathways through deep aquifers.
Applied to the Sydney–Gunnedah–Bowen Basin, one of Australia’s largest aquifer systems, the model reveals a stark contrast between coastal and inland groundwater. Coastal aquifers have relatively fast flow rates and water that is only about 2,000 years old, while inland aquifers move 60 times more slowly, with water that has been underground for roughly 400,000 years.
When the model is adjusted to account for the decline in borehole water levels observed since 2000, the results show that inland flow pathways shift significantly as groundwater is drawn further from recharge zones in a drying climate. This suggests that increasing water extraction from inland aquifers during drought could permanently redirect long-range underground flow paths — a finding with important implications for sustainable water management across Australia.
I am an ARC Industry Research Fellow in the School of Geography, Earth and Atmospheric Sciences at The University of Melbourne. I am an expert in fusing Earth evolution models with data to understand how groundwater moves critical minerals through the landscape. Related research interests include the cycling of volatiles within the Earth, probabilistic thermal models of the lithosphere to unravel past tectonic and climatic events, and understanding the how enigmatic volcanoes form.
I am a vocal advocate for the integral role of geoscience in responding to challenges we face in transitioning to the carbon-neutral economy. As an expert in my field, I have been interviewed in national and international print media, TV, and radio on a wide variety of subjects including earthquakes, volcanoes, groundwater, and critical minerals.
