Fig. 1: Groundwater-to-rainfall tritium ratio data and likelihood of focused recharge in Australia.
From: Focused groundwater recharge is controlled by landscape and climate
a Map of calculated groundwater-to-rainfall tritium ratios (3HG/3HP5), with locations of observed and interpolated rainfall tritium time series. Insets show zoomed-in views of selected regions: b Perth (Western Australia), c Darwin (Northern Territory), d Lower Burdekin (Queensland), and e Cobram (Victoria). f Conceptual time-series of annual rainfall tritium (3HP) decaying over time since peak tritium activities during nuclear-testing, showing the 5-year mean rainfall tritium (3HP5), groundwater tritium (3HG), and the equation for calculating 3HG/3HP5. g Relationship between groundwater depth in metres below ground surface (mbgs) and 3HG/3HP5, with points coloured by the likelihood of focused recharge (blue = high and grey = low) and fitted exponential decay curve.
