Articles | Volume 28, issue 7
https://doi.org/10.5194/hess-28-1771-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/hess-28-1771-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
17 Apr 2024
Research article |
| 17 Apr 2024
| 17 Apr 2024
A high-resolution map of diffuse groundwater recharge rates for Australia
Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, 8000, Australia
National Centre for Groundwater Research and Training, Adelaide, 5000, Australia
Dylan J. Irvine
Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, 8000, Australia
National Centre for Groundwater Research and Training, Adelaide, 5000, Australia
Clément Duvert
Research Institute for the Environment and Livelihoods, Charles Darwin University, Darwin, 8000, Australia
National Centre for Groundwater Research and Training, Adelaide, 5000, Australia
Gabriel C. Rau
National Centre for Groundwater Research and Training, Adelaide, 5000, Australia
School of Environmental and Life Sciences, the University of Newcastle, Callaghan, 2308, Australia
Ian Cartwright
National Centre for Groundwater Research and Training, Adelaide, 5000, Australia
School of Earth, Atmosphere and Environment, Monash University, Clayton, 3800, Australia
Related authors
No articles found.
Haegyeong Lee, Manuel Gossler, Kai Zosseder, Philipp Blum, Peter Bayer, and Gabriel C. Rau
EGUsphere, https://doi.org/10.5194/egusphere-2024-1949, https://doi.org/10.5194/egusphere-2024-1949, 2024
Short summary
Short summary
A systematic laboratory experiment elucidates two-phase heat transport due to water flow in saturated porous media to understand thermal propagation in aquifers. Results reveal delayed thermal arrival in the solid phase, depending on grain size and flow velocity. Analytical modeling using standard local thermal equilibrium (LTE) and advanced local thermal non-equilibrium (LTNE) theory fails to describe temperature breakthrough curves, highlighting the need for more advanced numerical approaches.
Patrick Haehnel, Todd C. Rasmussen, and Gabriel C. Rau
Hydrol. Earth Syst. Sci., 28, 2767–2784, https://doi.org/10.5194/hess-28-2767-2024, https://doi.org/10.5194/hess-28-2767-2024, 2024
Short summary
Short summary
While groundwater recharge is important for water resources management, nearshore sea levels can obscure this signal. Regression deconvolution has previously been used to remove other influences from groundwater levels (e.g., barometric pressure, Earth tides) by accounting for time-delayed responses from these influences. We demonstrate that it can also remove sea-level influences from measured groundwater levels.
Rémi Valois, Agnès Rivière, Jean-Michel Vouillamoz, and Gabriel C. Rau
Hydrol. Earth Syst. Sci., 28, 1041–1054, https://doi.org/10.5194/hess-28-1041-2024, https://doi.org/10.5194/hess-28-1041-2024, 2024
Short summary
Short summary
Characterizing aquifer systems is challenging because it is difficult to obtain in situ information. They can, however, be characterized using natural forces such as Earth tides. Models that account for more complex situations are still necessary to extend the use of Earth tides to assess hydromechanical properties of aquifer systems. Such a model is developed in this study and applied to a case study in Cambodia, where a combination of tides was used in order to better constrain the model.
Jose M. Bastias Espejo, Chris Turnadge, Russell S. Crosbie, Philipp Blum, and Gabriel C. Rau
Hydrol. Earth Syst. Sci., 27, 3447–3462, https://doi.org/10.5194/hess-27-3447-2023, https://doi.org/10.5194/hess-27-3447-2023, 2023
Short summary
Short summary
Analytical models estimate subsurface properties from subsurface–tidal load interactions. However, they have limited accuracy in representing subsurface physics and parameter estimation. We derived a new analytical solution which models flow to wells due to atmospheric tides. We applied it to field data and compared our findings with subsurface knowledge. Our results enhance understanding of subsurface systems, providing valuable information on their behavior.
Keirnan Fowler, Murray Peel, Margarita Saft, Tim J. Peterson, Andrew Western, Lawrence Band, Cuan Petheram, Sandra Dharmadi, Kim Seong Tan, Lu Zhang, Patrick Lane, Anthony Kiem, Lucy Marshall, Anne Griebel, Belinda E. Medlyn, Dongryeol Ryu, Giancarlo Bonotto, Conrad Wasko, Anna Ukkola, Clare Stephens, Andrew Frost, Hansini Gardiya Weligamage, Patricia Saco, Hongxing Zheng, Francis Chiew, Edoardo Daly, Glen Walker, R. Willem Vervoort, Justin Hughes, Luca Trotter, Brad Neal, Ian Cartwright, and Rory Nathan
Hydrol. Earth Syst. Sci., 26, 6073–6120, https://doi.org/10.5194/hess-26-6073-2022, https://doi.org/10.5194/hess-26-6073-2022, 2022
Short summary
Short summary
Recently, we have seen multi-year droughts tending to cause shifts in the relationship between rainfall and streamflow. In shifted catchments that have not recovered, an average rainfall year produces less streamflow today than it did pre-drought. We take a multi-disciplinary approach to understand why these shifts occur, focusing on Australia's over-10-year Millennium Drought. We evaluate multiple hypotheses against evidence, with particular focus on the key role of groundwater processes.
Zibo Zhou, Ian Cartwright, and Uwe Morgenstern
Hydrol. Earth Syst. Sci., 26, 4497–4513, https://doi.org/10.5194/hess-26-4497-2022, https://doi.org/10.5194/hess-26-4497-2022, 2022
Short summary
Short summary
Streams may receive water from different sources in their catchment. There is limited understanding of which water stores intermittent streams are connected to. Using geochemistry we show that the intermittent streams in southeast Australia are connected to younger smaller near-river water stores rather than regional groundwater. This makes these streams more vulnerable to the impacts of climate change and requires management of the riparian zone for their protection.
Gabriel C. Rau, Timothy C. McMillan, Martin S. Andersen, and Wendy A. Timms
Hydrol. Earth Syst. Sci., 26, 4301–4321, https://doi.org/10.5194/hess-26-4301-2022, https://doi.org/10.5194/hess-26-4301-2022, 2022
Short summary
Short summary
This work develops and applies a new method to estimate hydraulic and geomechanical subsurface properties in situ using standard groundwater and atmospheric pressure records. The estimated properties comply with expected values except for the Poisson ratio, which we attribute to the investigated scale and conditions. Our new approach can be used to cost-effectively investigate the subsurface using standard monitoring datasets.
Ian Cartwright
Hydrol. Earth Syst. Sci., 26, 183–195, https://doi.org/10.5194/hess-26-183-2022, https://doi.org/10.5194/hess-26-183-2022, 2022
Short summary
Short summary
Using specific conductivity (SC) to estimate groundwater inflow to rivers is complicated by bank return waters, interflow, and flows off floodplains contributing to baseflow in all but the driest years. Using the maximum SC of the river in dry years to estimate the SC of groundwater produces the best baseflow vs. streamflow trends. The variable composition of baseflow hinders calibration of hydrograph-based techniques to estimate groundwater inflows.
Danlu Guo, Camille Minaudo, Anna Lintern, Ulrike Bende-Michl, Shuci Liu, Kefeng Zhang, and Clément Duvert
Hydrol. Earth Syst. Sci., 26, 1–16, https://doi.org/10.5194/hess-26-1-2022, https://doi.org/10.5194/hess-26-1-2022, 2022
Short summary
Short summary
We investigate the impact of baseflow contribution on concentration–flow (C–Q) relationships across the Australian continent. We developed a novel Bayesian hierarchical model for six water quality variables across 157 catchments that span five climate zones. For sediments and nutrients, the C–Q slope is generally steeper for catchments with a higher median and a greater variability of baseflow contribution, highlighting the key role of variable flow pathways in particulate and solute export.
Michael Kilgour Stewart, Uwe Morgenstern, and Ian Cartwright
Hydrol. Earth Syst. Sci., 25, 6333–6338, https://doi.org/10.5194/hess-25-6333-2021, https://doi.org/10.5194/hess-25-6333-2021, 2021
Short summary
Short summary
The combined use of deuterium and tritium to determine travel time distributions in streams is an important development in catchment hydrology (Rodriguez et al., 2021). This comment, however, argues that their results do not generally invalidate the truncation hypothesis of Stewart et al. (2010) (i.e. that stable isotopes underestimate travel times through catchments), as they imply, but asserts instead that the hypothesis still applies to many other catchments.
José M. Bastías Espejo, Andy Wilkins, Gabriel C. Rau, and Philipp Blum
Geosci. Model Dev., 14, 6257–6272, https://doi.org/10.5194/gmd-14-6257-2021, https://doi.org/10.5194/gmd-14-6257-2021, 2021
Short summary
Short summary
The hydraulic and mechanical properties of the subsurface are inherently heterogeneous. RHEA is a simulator that can perform couple hydro-geomechanical processes in heterogeneous porous media with steep gradients. RHEA is able to fully integrate spatial heterogeneity, allowing allocation of distributed hydraulic and geomechanical properties at mesh element level. RHEA is a valuable tool that can simulate problems considering realistic heterogeneity inherent to geologic formations.
Dylan J. Irvine, Cameron Wood, Ian Cartwright, and Tanya Oliver
Hydrol. Earth Syst. Sci., 25, 5415–5424, https://doi.org/10.5194/hess-25-5415-2021, https://doi.org/10.5194/hess-25-5415-2021, 2021
Short summary
Short summary
It is widely assumed that 14C is in contact with the atmosphere until recharging water reaches the water table. Unsaturated zone (UZ) studies have shown that 14C decreases with depth below the land surface. We produce a relationship between UZ 14C and depth to the water table to estimate input 14C activities for groundwater age estimation. Application of the new relationship shows that it is important for UZ processes to be considered in groundwater mean residence time estimation.
Shovon Barua, Ian Cartwright, P. Evan Dresel, and Edoardo Daly
Hydrol. Earth Syst. Sci., 25, 89–104, https://doi.org/10.5194/hess-25-89-2021, https://doi.org/10.5194/hess-25-89-2021, 2021
Short summary
Short summary
We evaluate groundwater recharge rates in a semi-arid area that has undergone land-use changes. The widespread presence of old saline groundwater indicates that pre-land-clearing recharge rates were low and present-day recharge rates are still modest. The fluctuations of the water table and tritium activities reflect present-day recharge rates; however, the water table fluctuation estimates are unrealistically high, and this technique may not be suited for estimating recharge in semi-arid areas.
Gabriel C. Rau, Mark O. Cuthbert, R. Ian Acworth, and Philipp Blum
Hydrol. Earth Syst. Sci., 24, 6033–6046, https://doi.org/10.5194/hess-24-6033-2020, https://doi.org/10.5194/hess-24-6033-2020, 2020
Short summary
Short summary
This work provides an important generalisation of a previously developed method that quantifies subsurface barometric efficiency using the groundwater level response to Earth and atmospheric tides. The new approach additionally allows the quantification of hydraulic conductivity and specific storage. This enables improved and rapid assessment of subsurface processes and properties using standard pressure measurements.
Harald Hofmann, Dean Newborn, Ian Cartwright, Dioni I. Cendón, and Matthias Raiber
Hydrol. Earth Syst. Sci., 24, 1293–1318, https://doi.org/10.5194/hess-24-1293-2020, https://doi.org/10.5194/hess-24-1293-2020, 2020
Short summary
Short summary
Fresh groundwater (GW) on barrier islands is affected by GW use and precipitation variability. Mean residence times (MRTs) of GW on a sand barrier island were determined. They ranged from 37 years to more than 150 years for tritium and had a much larger range (modern to 5000 years) for carbon-14. Perched aquifer systems in the unsaturated zone and peat formations around wetlands are the most likely cause of longer MRTs, as they have a significant impact on regional recharge and flow diversion.
Gabriel C. Rau, Vincent E. A. Post, Margaret Shanafield, Torsten Krekeler, Eddie W. Banks, and Philipp Blum
Hydrol. Earth Syst. Sci., 23, 3603–3629, https://doi.org/10.5194/hess-23-3603-2019, https://doi.org/10.5194/hess-23-3603-2019, 2019
Short summary
Short summary
The flow of water is often inferred from water levels and gradients whose measurements are considered trivial despite the many steps and complexity of the instruments involved. We systematically review the four measurement steps required and summarise the systematic errors. To determine the accuracy with which flow can be resolved, we quantify and propagate the random errors. Our results illustrate the limitations of current practice and provide concise recommendations to improve data quality.
William Howcroft, Ian Cartwright, and Uwe Morgenstern
Hydrol. Earth Syst. Sci., 22, 635–653, https://doi.org/10.5194/hess-22-635-2018, https://doi.org/10.5194/hess-22-635-2018, 2018
Short summary
Short summary
Documenting mean transit times is critical for understanding and managing catchments. Mean transit times in six headwater catchments of the Otway Ranges, Australia, determined using tritium, range from 7 to 230 years. Tritium activities correlate well with streamflow but are difficult to predict from catchment attributes or major ion geochemistry. The long mean transit times suggest that the catchments are buffered from short-term rainfall variations.
Ian Cartwright and Uwe Morgenstern
Hydrol. Earth Syst. Sci., 20, 4757–4773, https://doi.org/10.5194/hess-20-4757-2016, https://doi.org/10.5194/hess-20-4757-2016, 2016
Short summary
Short summary
This research used tritium to determine the timescales that water is stored in peatlands and eucalyptus forest catchments in upland river systems in southeast Australia. The mean transit times in the peatland catchments of less than a few years contrast with much longer transit times (years to decades) in adjacent eucalyptus catchments. The peat is susceptible to drying which renders it vulnerable to degradation and bushfire and does not represent a long-term water store to upland streams.
Katie Coleborn, Gabriel C. Rau, Mark O. Cuthbert, Andy Baker, and Owen Navarre
Hydrol. Earth Syst. Sci., 20, 4439–4455, https://doi.org/10.5194/hess-20-4439-2016, https://doi.org/10.5194/hess-20-4439-2016, 2016
Short summary
Short summary
This is the first observation of tree water use in cave drip water. Our novel time series analysis using the synchrosqueeze transform identified daily and sub-daily oscillations in drip rate. The only hypothesis consistent with hydrologic theory and the data was that the oscillations were caused by solar driven pumping by trees above the cave. We propose a new protocol for inferring karst architecture and our findings support research on the impact trees on speleothem paleoclimate proxies.
Ian Cartwright and Harald Hofmann
Hydrol. Earth Syst. Sci., 20, 3581–3600, https://doi.org/10.5194/hess-20-3581-2016, https://doi.org/10.5194/hess-20-3581-2016, 2016
Short summary
Short summary
This paper uses the natural geochemical tracer Rn together with streamflow measurements to differentiate between actual groundwater inflows and water that exits the river, flows through the near-river sediments, and subsequently re-enters the river downstream (parafluvial flow). Distinguishing between these two components is important to understanding the water balance in gaining streams and in managing and protecting surface water resources.
C. Duvert, M. K. Stewart, D. I. Cendón, and M. Raiber
Hydrol. Earth Syst. Sci., 20, 257–277, https://doi.org/10.5194/hess-20-257-2016, https://doi.org/10.5194/hess-20-257-2016, 2016
Short summary
Short summary
The transit time of water is a key indicator of hydrological processes at the catchment scale. Our results suggest that the use of tritium time series in streamwater can be highly valuable for assessing the temporal variations in the transit time of older groundwater contributions to streamflow. We also show that, shortly after high flow events, the transit time of the old water fraction increases and tends to approach the groundwater residence time.
I. Cartwright and U. Morgenstern
Hydrol. Earth Syst. Sci., 19, 3771–3785, https://doi.org/10.5194/hess-19-3771-2015, https://doi.org/10.5194/hess-19-3771-2015, 2015
Short summary
Short summary
This study documents the age of water that contributes to rivers in upper catchments using the radioactive tracer tritium. River water in the upper Ovens Valley (Australia) is several years to decades old and water from different parts of the catchment (e.g., soil, regolith, and groundwater) is mobilised at different flow conditions. The results indicate that these rivers are buffered against short term climate variability but are susceptible to longer-term climate and land use changes
N. P. Unland, I. Cartwright, D. I. Cendón, and R. Chisari
Hydrol. Earth Syst. Sci., 18, 5109–5124, https://doi.org/10.5194/hess-18-5109-2014, https://doi.org/10.5194/hess-18-5109-2014, 2014
Short summary
Short summary
Periodic flooding of rivers should result in increased groundwater recharge near rivers and thus - younger and fresher groundwater near rivers. This study found the age and salinity of shallow groundwater to increase with proximity to the Tambo River in South East Australia. This appears to be due to the upwelling of older, regional groundwater closer the river. Other chemical parameters are consistent with this. This is a process that may be occurring in other similar river systems.
A. P. Atkinson, I. Cartwright, B. S. Gilfedder, D. I. Cendón, N. P. Unland, and H. Hofmann
Hydrol. Earth Syst. Sci., 18, 4951–4964, https://doi.org/10.5194/hess-18-4951-2014, https://doi.org/10.5194/hess-18-4951-2014, 2014
Short summary
Short summary
This research article uses of radiogenic isotopes, stable isotopes and groundwater geochemistry to study groundwater age and recharge processes in the Gellibrand Valley, a relatively unstudied catchment and potential groundwater resource. The valley is found to contain both "old", regionally recharged groundwater (300-10,000 years) in the near-river environment, and modern groundwater (0-100 years old) further back on the floodplain. There is no recharge of the groundwater by high river flows.
I. Cartwright, B. Gilfedder, and H. Hofmann
Hydrol. Earth Syst. Sci., 18, 15–30, https://doi.org/10.5194/hess-18-15-2014, https://doi.org/10.5194/hess-18-15-2014, 2014
M. C. L. Yu, I. Cartwright, J. L. Braden, and S. T. de Bree
Hydrol. Earth Syst. Sci., 17, 4907–4924, https://doi.org/10.5194/hess-17-4907-2013, https://doi.org/10.5194/hess-17-4907-2013, 2013
N. P. Unland, I. Cartwright, M. S. Andersen, G. C. Rau, J. Reed, B. S. Gilfedder, A. P. Atkinson, and H. Hofmann
Hydrol. Earth Syst. Sci., 17, 3437–3453, https://doi.org/10.5194/hess-17-3437-2013, https://doi.org/10.5194/hess-17-3437-2013, 2013
Related subject area
Subject: Groundwater hydrology | Techniques and Approaches: Modelling approaches
Data-driven modelling of hydraulic-head time series: results and lessons learned from the 2022 Groundwater Time Series Modelling Challenge
The impact of future changes in climate variables and groundwater abstraction on basin-scale groundwater availability
Assessing groundwater level modelling using a 1-D convolutional neural network (CNN): linking model performances to geospatial and time series features
Short high-accuracy tritium data time series for assessing groundwater mean transit times in the vadose and saturated zones of the Luxembourg Sandstone aquifer
High-resolution long-term average groundwater recharge in Africa estimated using random forest regression and residual interpolation
Towards understanding the influence of seasons on low-groundwater periods based on explainable machine learning
Training deep learning models with a multi-station approach and static aquifer attributes for groundwater level simulation: what’s the best way to leverage regionalised information?
Shannon entropy of transport self-organization due to dissolution–precipitation reaction at varying Peclet numbers in initially homogeneous porous media
Influence of bank slope on sinuosity-driven hyporheic exchange flow and residence time distribution during a dynamic flood event
Technical note: A model of chemical transport in a wellbore–aquifer system
Disentangling coastal groundwater level dynamics in a global dataset
Current and future roles of meltwater–groundwater dynamics in a proglacial Alpine outwash plain
On the challenges of global entity-aware deep learning models for groundwater level prediction
Incorporating interpretation uncertainties from deterministic 3D hydrostratigraphic models in groundwater models
Adjoint subordination to calculate backward travel time probability of pollutants in water with various velocity resolutions
On the optimal level of complexity for the representation of groundwater-dependent wetland systems in land surface models
Estimation of groundwater age distributions from hydrochemistry: comparison of two metamodelling algorithms in the Heretaunga Plains aquifer system, New Zealand
Technical note: Novel analytical solution for groundwater response to atmospheric tides
Calibration of groundwater seepage against the spatial distribution of the stream network to assess catchment-scale hydraulic properties
Climate-warming-driven changes in the cryosphere and their impact on groundwater–surface-water interactions in the Heihe River basin
Comparison of artificial neural networks and reservoir models for simulating karst spring discharge on five test sites in the Alpine and Mediterranean regions
A general model of radial dispersion with wellbore mixing and skin effects
Estimation of hydraulic conductivity functions in karst regions by particle swarm optimization with application to Lake Vrana, Croatia
The origin of hydrological responses following earthquakes in a confined aquifer: insight from water level, flow rate, and temperature observations
Advance prediction of coastal groundwater levels with temporal convolutional and long short-term memory networks
Three-dimensional hydrogeological parametrization using sparse piezometric data
Machine-learning-based downscaling of modelled climate change impacts on groundwater table depth
Frequency domain water table fluctuations reveal impacts of intense rainfall and vadose zone thickness on groundwater recharge
Characterizing groundwater heat transport in a complex lowland aquifer using paleo-temperature reconstruction, satellite data, temperature–depth profiles, and numerical models
Karst spring recession and classification: efficient, automated methods for both fast- and slow-flow components
Exploring river–aquifer interactions and hydrological system response using baseflow separation, impulse response modeling, and time series analysis in three temperate lowland catchments
Experimental study of non-Darcy flow characteristics in permeable stones
Karst spring discharge modeling based on deep learning using spatially distributed input data
HESS Opinions: Chemical transport modeling in subsurface hydrological systems – space, time, and the “holy grail” of “upscaling”
Spatiotemporal variations in water sources and mixing spots in a riparian zone
Delineation of discrete conduit networks in karst aquifers via combined analysis of tracer tests and geophysical data
Reactive transport modeling for supporting climate resilience at groundwater contamination sites
Improved understanding of regional groundwater drought development through time series modelling: the 2018–2019 drought in the Netherlands
Simulation of long-term spatiotemporal variations in regional-scale groundwater recharge: contributions of a water budget approach in cold and humid climates
Feedback mechanisms between precipitation and dissolution reactions across randomly heterogeneous conductivity fields
Taking theory to the field: streamflow generation mechanisms in an intermittent Mediterranean catchment
Coupling saturated and unsaturated flow: comparing the iterative and the non-iterative approach
Time lags of nitrate, chloride, and tritium in streams assessed by dynamic groundwater flow tracking in a lowland landscape
Using Long Short-Term Memory networks to connect water table depth anomalies to precipitation anomalies over Europe
Estimation of groundwater recharge from groundwater levels using nonlinear transfer function noise models and comparison to lysimeter data
Early hypogenic carbonic acid speleogenesis in unconfined limestone aquifers by upwelling deep-seated waters with high CO2 concentration: a modelling approach
Impacts of climate change on groundwater flooding and ecohydrology in lowland karst
How daily groundwater table drawdown affects the diel rhythm of hyporheic exchange
Groundwater level forecasting with artificial neural networks: a comparison of long short-term memory (LSTM), convolutional neural networks (CNNs), and non-linear autoregressive networks with exogenous input (NARX)
Groundwater and baseflow drought responses to synthetic recharge stress tests
Raoul A. Collenteur, Ezra Haaf, Mark Bakker, Tanja Liesch, Andreas Wunsch, Jenny Soonthornrangsan, Jeremy White, Nick Martin, Rui Hugman, Ed de Sousa, Didier Vanden Berghe, Xinyang Fan, Tim J. Peterson, Jānis Bikše, Antoine Di Ciacca, Xinyue Wang, Yang Zheng, Maximilian Nölscher, Julian Koch, Raphael Schneider, Nikolas Benavides Höglund, Sivarama Krishna Reddy Chidepudi, Abel Henriot, Nicolas Massei, Abderrahim Jardani, Max Gustav Rudolph, Amir Rouhani, J. Jaime Gómez-Hernández, Seifeddine Jomaa, Anna Pölz, Tim Franken, Morteza Behbooei, Jimmy Lin, and Rojin Meysami
Hydrol. Earth Syst. Sci., 28, 5193–5208, https://doi.org/10.5194/hess-28-5193-2024, https://doi.org/10.5194/hess-28-5193-2024, 2024
Short summary
Short summary
We show the results of the 2022 Groundwater Time Series Modelling Challenge; 15 teams applied data-driven models to simulate hydraulic heads, and three model groups were identified: lumped, machine learning, and deep learning. For all wells, reasonable performance was obtained by at least one team from each group. There was not one team that performed best for all wells. In conclusion, the challenge was a successful initiative to compare different models and learn from each other.
Steven Reinaldo Rusli, Victor F. Bense, Syed M. T. Mustafa, and Albrecht H. Weerts
Hydrol. Earth Syst. Sci., 28, 5107–5131, https://doi.org/10.5194/hess-28-5107-2024, https://doi.org/10.5194/hess-28-5107-2024, 2024
Short summary
Short summary
In this paper, we investigate the impact of climatic and anthropogenic factors on future groundwater availability. The changes are simulated using hydrological and groundwater flow models. We find that future groundwater status is influenced more by anthropogenic factors than climatic factors. The results are beneficial for informing responsible parties in operational water management about achieving future (ground)water governance.
Mariana Gomez, Maximilian Nölscher, Andreas Hartmann, and Stefan Broda
Hydrol. Earth Syst. Sci., 28, 4407–4425, https://doi.org/10.5194/hess-28-4407-2024, https://doi.org/10.5194/hess-28-4407-2024, 2024
Short summary
Short summary
To understand the impact of external factors on groundwater level modelling using a 1-D convolutional neural network (CNN) model, we train, validate, and tune individual CNN models for 505 wells distributed across Lower Saxony, Germany. We then evaluate the performance of these models against available geospatial and time series features. This study provides new insights into the relationship between these factors and the accuracy of groundwater modelling.
Laurent Gourdol, Michael K. Stewart, Uwe Morgenstern, and Laurent Pfister
Hydrol. Earth Syst. Sci., 28, 3519–3547, https://doi.org/10.5194/hess-28-3519-2024, https://doi.org/10.5194/hess-28-3519-2024, 2024
Short summary
Short summary
Determining water transit times in aquifers is key to a better understanding of groundwater resources and their sustainable management. For our research, we used high-accuracy tritium data from 35 springs draining the Luxembourg Sandstone aquifer. We assessed the mean transit times of groundwater and found that water moves on average more than 10 times more slowly vertically in the vadose zone of the aquifer (~12 m yr-1) than horizontally in its saturated zone (~170 m yr-1).
Anna Pazola, Mohammad Shamsudduha, Jon French, Alan M. MacDonald, Tamiru Abiye, Ibrahim Baba Goni, and Richard G. Taylor
Hydrol. Earth Syst. Sci., 28, 2949–2967, https://doi.org/10.5194/hess-28-2949-2024, https://doi.org/10.5194/hess-28-2949-2024, 2024
Short summary
Short summary
This study advances groundwater research using a high-resolution random forest model, revealing new recharge areas and spatial variability, mainly in humid regions. Limited data in rainy zones is a constraint for the model. Our findings underscore the promise of machine learning for large-scale groundwater modelling while further emphasizing the importance of data collection for robust results.
Andreas Wunsch, Tanja Liesch, and Nico Goldscheider
Hydrol. Earth Syst. Sci., 28, 2167–2178, https://doi.org/10.5194/hess-28-2167-2024, https://doi.org/10.5194/hess-28-2167-2024, 2024
Short summary
Short summary
Seasons have a strong influence on groundwater levels, but relationships are complex and partly unknown. Using data from wells in Germany and an explainable machine learning approach, we showed that summer precipitation is the key factor that controls the severeness of a low-water period in fall; high summer temperatures do not per se cause stronger decreases. Preceding winters have only a minor influence on such low-water periods in general.
Sivarama Krishna Reddy Chidepudi, Nicolas Massei, Abderrahim Jardani, Bastien Dieppois, Abel Henriot, and Matthieu Fournier
EGUsphere, https://doi.org/10.5194/egusphere-2024-794, https://doi.org/10.5194/egusphere-2024-794, 2024
Short summary
Short summary
This study explores how deep learning can improve our understanding of groundwater levels, using an approach that combines climate data and physical characteristics of aquifers. By focusing on different types of groundwater levels and employing techniques like clustering and wavelet transform, the study highlights the importance of targeting relevant information. This research not only advances groundwater simulation but also emphasizes the benefits of different modelling approaches.
Evgeny Shavelzon and Yaniv Edery
Hydrol. Earth Syst. Sci., 28, 1803–1826, https://doi.org/10.5194/hess-28-1803-2024, https://doi.org/10.5194/hess-28-1803-2024, 2024
Short summary
Short summary
We investigate the interaction of transport with dissolution–precipitation reactions in porous media using the concepts of entropy and work to quantify the emergence of preferential flow paths. We show that the preferential-flow-path phenomenon and the hydraulic power required to maintain the driving pressure drop intensify over time along with the heterogeneity due to the interaction between the transport and the reactive processes. This is more pronounced in diffusion-dominated flows.
Yiming Li, Uwe Schneidewind, Zhang Wen, Stefan Krause, and Hui Liu
Hydrol. Earth Syst. Sci., 28, 1751–1769, https://doi.org/10.5194/hess-28-1751-2024, https://doi.org/10.5194/hess-28-1751-2024, 2024
Short summary
Short summary
Meandering rivers are an integral part of many landscapes around the world. Here we used a new modeling approach to look at how the slope of riverbanks influences water flow and solute transport from a meandering river channel through its bank and into/out of the connected groundwater compartment (aquifer). We found that the bank slope can be a significant factor to be considered, especially when bank slope angles are small, and riverbank and aquifer conditions only allow for slow water flow.
Yiqun Gan and Quanrong Wang
Hydrol. Earth Syst. Sci., 28, 1317–1323, https://doi.org/10.5194/hess-28-1317-2024, https://doi.org/10.5194/hess-28-1317-2024, 2024
Short summary
Short summary
1. A revised 3D model of solute transport is developed in the well–aquifer system. 2. The accuracy of the new model is tested against benchmark analytical solutions. 3. Previous models overestimate the concentration of solute in both aquifers and wellbores in the injection well test case. 4. Previous models underestimate the concentration in the extraction well test case.
Annika Nolte, Ezra Haaf, Benedikt Heudorfer, Steffen Bender, and Jens Hartmann
Hydrol. Earth Syst. Sci., 28, 1215–1249, https://doi.org/10.5194/hess-28-1215-2024, https://doi.org/10.5194/hess-28-1215-2024, 2024
Short summary
Short summary
This study examines about 8000 groundwater level (GWL) time series from five continents to explore similarities in groundwater systems at different scales. Statistical metrics and machine learning techniques are applied to identify common GWL dynamics patterns and analyze their controlling factors. The study also highlights the potential and limitations of this data-driven approach to improve our understanding of groundwater recharge and discharge processes.
Tom Müller, Matteo Roncoroni, Davide Mancini, Stuart N. Lane, and Bettina Schaefli
Hydrol. Earth Syst. Sci., 28, 735–759, https://doi.org/10.5194/hess-28-735-2024, https://doi.org/10.5194/hess-28-735-2024, 2024
Short summary
Short summary
We investigate the role of a newly formed floodplain in an alpine glaciated catchment to store and release water. Based on field measurements, we built a numerical model to simulate the water fluxes and show that recharge occurs mainly due to the ice-melt-fed river. We identify three future floodplains, which could emerge from glacier retreat, and show that their combined storage leads to some additional groundwater storage but contributes little additional baseflow for the downstream river.
Benedikt Heudorfer, Tanja Liesch, and Stefan Broda
Hydrol. Earth Syst. Sci., 28, 525–543, https://doi.org/10.5194/hess-28-525-2024, https://doi.org/10.5194/hess-28-525-2024, 2024
Short summary
Short summary
We build a neural network to predict groundwater levels from monitoring wells. We predict all wells at the same time, by learning the differences between wells with static features, making it an entity-aware global model. This works, but we also test different static features and find that the model does not use them to learn exactly how the wells are different, but only to uniquely identify them. As this model class is not actually entity aware, we suggest further steps to make it so.
Trine Enemark, Rasmus Bødker Madsen, Torben O. Sonnenborg, Lærke Therese Andersen, Peter B. E. Sandersen, Jacob Kidmose, Ingelise Møller, Thomas Mejer Hansen, Karsten Høgh Jensen, and Anne-Sophie Høyer
Hydrol. Earth Syst. Sci., 28, 505–523, https://doi.org/10.5194/hess-28-505-2024, https://doi.org/10.5194/hess-28-505-2024, 2024
Short summary
Short summary
In this study, we demonstrate an approach to evaluate the interpretation uncertainty within a manually interpreted geological model in a groundwater model. Using qualitative estimates of uncertainties, several geological realizations are developed and implemented in groundwater models. We confirm existing evidence that if the conceptual model is well defined, interpretation uncertainties within the conceptual model have limited impact on groundwater model predictions.
Yong Zhang, Graham E. Fogg, HongGuang Sun, Donald M. Reeves, Roseanna M. Neupauer, and Wei Wei
Hydrol. Earth Syst. Sci., 28, 179–203, https://doi.org/10.5194/hess-28-179-2024, https://doi.org/10.5194/hess-28-179-2024, 2024
Short summary
Short summary
Pollutant release history and source identification are helpful for managing water resources, but it remains a challenge to reliably identify such information for real-world, complex transport processes in rivers and aquifers. In this study, we filled this knowledge gap by deriving a general backward governing equation and developing the efficient solver. Field applications showed that this model and solver are applicable for a broad range of flow systems, dimensions, and spatiotemporal scales.
Mennatullah T. Elrashidy, Andrew M. Ireson, and Saman Razavi
Hydrol. Earth Syst. Sci., 27, 4595–4608, https://doi.org/10.5194/hess-27-4595-2023, https://doi.org/10.5194/hess-27-4595-2023, 2023
Short summary
Short summary
Wetlands are important ecosystems that store carbon and play a vital role in the water cycle. However, hydrological computer models do not always represent wetlands and their interaction with groundwater accurately. We tested different possible ways to include groundwater–wetland interactions in these models. We found that the optimal method to include wetlands and groundwater in the models is reliant on the intended use of the models and the characteristics of the land and soil being studied.
Conny Tschritter, Christopher J. Daughney, Sapthala Karalliyadda, Brioch Hemmings, Uwe Morgenstern, and Catherine Moore
Hydrol. Earth Syst. Sci., 27, 4295–4316, https://doi.org/10.5194/hess-27-4295-2023, https://doi.org/10.5194/hess-27-4295-2023, 2023
Short summary
Short summary
Understanding groundwater travel time (groundwater age) is crucial for tracking flow and contaminants. While groundwater age is usually inferred from age tracers, this study utilised two machine learning techniques with common groundwater chemistry data. The results of both methods correspond to traditional approaches. They are useful where hydrochemistry data exist but age tracer data are limited. These methods could help enhance our knowledge, aiding in sustainable freshwater management.
Jose M. Bastias Espejo, Chris Turnadge, Russell S. Crosbie, Philipp Blum, and Gabriel C. Rau
Hydrol. Earth Syst. Sci., 27, 3447–3462, https://doi.org/10.5194/hess-27-3447-2023, https://doi.org/10.5194/hess-27-3447-2023, 2023
Short summary
Short summary
Analytical models estimate subsurface properties from subsurface–tidal load interactions. However, they have limited accuracy in representing subsurface physics and parameter estimation. We derived a new analytical solution which models flow to wells due to atmospheric tides. We applied it to field data and compared our findings with subsurface knowledge. Our results enhance understanding of subsurface systems, providing valuable information on their behavior.
Ronan Abhervé, Clément Roques, Alexandre Gauvain, Laurent Longuevergne, Stéphane Louaisil, Luc Aquilina, and Jean-Raynald de Dreuzy
Hydrol. Earth Syst. Sci., 27, 3221–3239, https://doi.org/10.5194/hess-27-3221-2023, https://doi.org/10.5194/hess-27-3221-2023, 2023
Short summary
Short summary
We propose a model calibration method constraining groundwater seepage in the hydrographic network. The method assesses the hydraulic properties of aquifers in regions where perennial streams are directly fed by groundwater. The estimated hydraulic conductivity appear to be highly sensitive to the spatial extent and density of streams. Such an approach improving subsurface characterization from surface information is particularly interesting for ungauged basins.
Amanda Triplett and Laura E. Condon
Hydrol. Earth Syst. Sci., 27, 2763–2785, https://doi.org/10.5194/hess-27-2763-2023, https://doi.org/10.5194/hess-27-2763-2023, 2023
Short summary
Short summary
Accelerated melting in mountains is a global phenomenon. The Heihe River basin depends on upstream mountains for its water supply. We built a hydrologic model to examine how shifts in streamflow and warming will impact ground and surface water interactions. The results indicate that degrading permafrost has a larger effect than melting glaciers. Additionally, warming temperatures tend to have more impact than changes to streamflow. These results can inform other mountain–valley system studies.
Guillaume Cinkus, Andreas Wunsch, Naomi Mazzilli, Tanja Liesch, Zhao Chen, Nataša Ravbar, Joanna Doummar, Jaime Fernández-Ortega, Juan Antonio Barberá, Bartolomé Andreo, Nico Goldscheider, and Hervé Jourde
Hydrol. Earth Syst. Sci., 27, 1961–1985, https://doi.org/10.5194/hess-27-1961-2023, https://doi.org/10.5194/hess-27-1961-2023, 2023
Short summary
Short summary
Numerous modelling approaches can be used for studying karst water resources, which can make it difficult for a stakeholder or researcher to choose the appropriate method. We conduct a comparison of two widely used karst modelling approaches: artificial neural networks (ANNs) and reservoir models. Results show that ANN models are very flexible and seem great for reproducing high flows. Reservoir models can work with relatively short time series and seem to accurately reproduce low flows.
Wenguang Shi, Quanrong Wang, Hongbin Zhan, Renjie Zhou, and Haitao Yan
Hydrol. Earth Syst. Sci., 27, 1891–1908, https://doi.org/10.5194/hess-27-1891-2023, https://doi.org/10.5194/hess-27-1891-2023, 2023
Short summary
Short summary
The mechanism of radial dispersion is important for understanding reactive transport in the subsurface and for estimating aquifer parameters required in the optimization design of remediation strategies. A general model and associated analytical solutions are developed in this study. The new model represents the most recent advancement on radial dispersion studies and incorporates a host of important processes that are not taken into consideration in previous investigations.
Vanja Travaš, Luka Zaharija, Davor Stipanić, and Siniša Družeta
Hydrol. Earth Syst. Sci., 27, 1343–1359, https://doi.org/10.5194/hess-27-1343-2023, https://doi.org/10.5194/hess-27-1343-2023, 2023
Short summary
Short summary
In order to model groundwater flow in karst aquifers, it is necessary to approximate the influence of the unknown and irregular structure of the karst conduits. For this purpose, a procedure based on inverse modeling is adopted. Moreover, in order to reconstruct the functional dependencies related to groundwater flow, the particle swarm method was used, through which the optimal solution of unknown functions is found by imitating the movement of ants in search of food.
Shouchuan Zhang, Zheming Shi, Guangcai Wang, Zuochen Zhang, and Huaming Guo
Hydrol. Earth Syst. Sci., 27, 401–415, https://doi.org/10.5194/hess-27-401-2023, https://doi.org/10.5194/hess-27-401-2023, 2023
Short summary
Short summary
We documented the step-like increases of water level, flow rate, and water temperatures in a confined aquifer following multiple earthquakes. By employing tidal analysis and a coupled temperature and flow rate model, we find that post-seismic vertical permeability changes and recharge model could explain the co-seismic response. And co-seismic temperature changes are caused by mixing of different volumes of water, with the mixing ratio varying according to each earthquake.
Xiaoying Zhang, Fan Dong, Guangquan Chen, and Zhenxue Dai
Hydrol. Earth Syst. Sci., 27, 83–96, https://doi.org/10.5194/hess-27-83-2023, https://doi.org/10.5194/hess-27-83-2023, 2023
Short summary
Short summary
In a data-driven framework, groundwater levels can generally only be calculated 1 time step ahead. We discuss the advance prediction with longer forecast periods rather than single time steps by constructing a model based on a temporal convolutional network. Model accuracy and efficiency were further compared with an LSTM-based model. The two models derived in this study can help people cope with the uncertainty of what might occur in hydrological scenarios under the threat of climate change.
Dimitri Rambourg, Raphaël Di Chiara, and Philippe Ackerer
Hydrol. Earth Syst. Sci., 26, 6147–6162, https://doi.org/10.5194/hess-26-6147-2022, https://doi.org/10.5194/hess-26-6147-2022, 2022
Short summary
Short summary
The reproduction of flows and contaminations underground requires a good estimation of the parameters of the geological environment (mainly permeability and porosity), in three dimensions. While most researchers rely on geophysical methods, which are costly and difficult to implement in the field, this study proposes an alternative using data that are already widely available: piezometric records (monitoring of the water table) and the lithological description of the piezometric wells.
Raphael Schneider, Julian Koch, Lars Troldborg, Hans Jørgen Henriksen, and Simon Stisen
Hydrol. Earth Syst. Sci., 26, 5859–5877, https://doi.org/10.5194/hess-26-5859-2022, https://doi.org/10.5194/hess-26-5859-2022, 2022
Short summary
Short summary
Hydrological models at high spatial resolution are computationally expensive. However, outputs from such models, such as the depth of the groundwater table, are often desired in high resolution. We developed a downscaling algorithm based on machine learning that allows us to increase spatial resolution of hydrological model outputs, alleviating computational burden. We successfully applied the downscaling algorithm to the climate-change-induced impacts on the groundwater table across Denmark.
Luca Guillaumot, Laurent Longuevergne, Jean Marçais, Nicolas Lavenant, and Olivier Bour
Hydrol. Earth Syst. Sci., 26, 5697–5720, https://doi.org/10.5194/hess-26-5697-2022, https://doi.org/10.5194/hess-26-5697-2022, 2022
Short summary
Short summary
Recharge, defining the renewal rate of groundwater resources, is difficult to estimate at basin scale. Here, recharge variations are inferred from water table variations recorded in boreholes. First, results show that aquifer-scale properties controlling these variations can be inferred from boreholes. Second, groundwater is recharged by both intense and seasonal rainfall. Third, the short-term contribution appears overestimated in recharge models and depends on the unsaturated zone thickness.
Alberto Casillas-Trasvina, Bart Rogiers, Koen Beerten, Laurent Wouters, and Kristine Walraevens
Hydrol. Earth Syst. Sci., 26, 5577–5604, https://doi.org/10.5194/hess-26-5577-2022, https://doi.org/10.5194/hess-26-5577-2022, 2022
Short summary
Short summary
Heat in the subsurface can be used to characterize aquifer flow behaviour. The temperature data obtained can be useful for understanding the groundwater flow, which is of particular importance in waste disposal studies. Satellite images of surface temperature and a temperature–time curve were implemented in a heat transport model. Results indicate that conduction plays a major role in the aquifer and support the usefulness of temperature measurements.
Tunde Olarinoye, Tom Gleeson, and Andreas Hartmann
Hydrol. Earth Syst. Sci., 26, 5431–5447, https://doi.org/10.5194/hess-26-5431-2022, https://doi.org/10.5194/hess-26-5431-2022, 2022
Short summary
Short summary
Analysis of karst spring recession is essential for management of groundwater. In karst, recession is dominated by slow and fast components; separating these components is by manual and subjective approaches. In our study, we tested the applicability of automated streamflow recession extraction procedures for a karst spring. Results showed that, by simple modification, streamflow extraction methods can identify slow and fast components: derived recession parameters are within reasonable ranges.
Min Lu, Bart Rogiers, Koen Beerten, Matej Gedeon, and Marijke Huysmans
Hydrol. Earth Syst. Sci., 26, 3629–3649, https://doi.org/10.5194/hess-26-3629-2022, https://doi.org/10.5194/hess-26-3629-2022, 2022
Short summary
Short summary
Lowland rivers and shallow aquifers are closely coupled. We study their interactions here using a combination of impulse response modeling and hydrological data analysis. The results show that the lowland catchments are groundwater dominated and that the hydrological system from precipitation impulse to groundwater inflow response is a very fast response regime. This study also provides an alternative method to estimate groundwater inflow to rivers from the perspective of groundwater level.
Zhongxia Li, Junwei Wan, Tao Xiong, Hongbin Zhan, Linqing He, and Kun Huang
Hydrol. Earth Syst. Sci., 26, 3359–3375, https://doi.org/10.5194/hess-26-3359-2022, https://doi.org/10.5194/hess-26-3359-2022, 2022
Short summary
Short summary
Four permeable rocks with different pore sizes were considered to provide experimental evidence of Forchheimer flow and the transition between different flow regimes. The mercury injection technique was used to measure the pore size distribution, which is an essential factor for determining the flow regime, for four permeable stones. Finally, the influences of porosity and particle size on the Forchheimer coefficients were discussed.
Andreas Wunsch, Tanja Liesch, Guillaume Cinkus, Nataša Ravbar, Zhao Chen, Naomi Mazzilli, Hervé Jourde, and Nico Goldscheider
Hydrol. Earth Syst. Sci., 26, 2405–2430, https://doi.org/10.5194/hess-26-2405-2022, https://doi.org/10.5194/hess-26-2405-2022, 2022
Short summary
Short summary
Modeling complex karst water resources is difficult enough, but often there are no or too few climate stations available within or close to the catchment to deliver input data for modeling purposes. We apply image recognition algorithms to time-distributed, spatially gridded meteorological data to simulate karst spring discharge. Our models can also learn the approximate catchment location of a spring independently.
Brian Berkowitz
Hydrol. Earth Syst. Sci., 26, 2161–2180, https://doi.org/10.5194/hess-26-2161-2022, https://doi.org/10.5194/hess-26-2161-2022, 2022
Short summary
Short summary
Extensive efforts have focused on quantifying conservative chemical transport in geological formations. We assert that an explicit accounting of temporal information, under uncertainty, in addition to spatial information, is fundamental to an effective modeling formulation. We further assert that efforts to apply chemical transport equations at large length scales, based on measurements and model parameter values relevant to significantly smaller length scales, are an unattainable
holy grail.
Guilherme E. H. Nogueira, Christian Schmidt, Daniel Partington, Philip Brunner, and Jan H. Fleckenstein
Hydrol. Earth Syst. Sci., 26, 1883–1905, https://doi.org/10.5194/hess-26-1883-2022, https://doi.org/10.5194/hess-26-1883-2022, 2022
Short summary
Short summary
In near-stream aquifers, mixing between stream water and ambient groundwater can lead to dilution and the removal of substances that can be harmful to the water ecosystem at high concentrations. We used a numerical model to track the spatiotemporal evolution of different water sources and their mixing around a stream, which are rather difficult in the field. Results show that mixing mainly develops as narrow spots, varying In time and space, and is affected by magnitudes of discharge events.
Jacques Bodin, Gilles Porel, Benoît Nauleau, and Denis Paquet
Hydrol. Earth Syst. Sci., 26, 1713–1726, https://doi.org/10.5194/hess-26-1713-2022, https://doi.org/10.5194/hess-26-1713-2022, 2022
Short summary
Short summary
Assessment of the karst network geometry is an important challenge in the accurate modeling of karst aquifers. In this study, we propose an approach for the identification of effective three-dimensional discrete karst conduit networks conditioned on tracer tests and geophysical data. The applicability of the proposed approach is illustrated through a case study at the Hydrogeological Experimental Site in Poitiers, France.
Zexuan Xu, Rebecca Serata, Haruko Wainwright, Miles Denham, Sergi Molins, Hansell Gonzalez-Raymat, Konstantin Lipnikov, J. David Moulton, and Carol Eddy-Dilek
Hydrol. Earth Syst. Sci., 26, 755–773, https://doi.org/10.5194/hess-26-755-2022, https://doi.org/10.5194/hess-26-755-2022, 2022
Short summary
Short summary
Climate change could change the groundwater system and threaten water supply. To quantitatively evaluate its impact on water quality, numerical simulations with chemical and reaction processes are required. With the climate projection dataset, we used the newly developed hydrological and chemical model to investigate the movement of contaminants and assist the management of contamination sites.
Esther Brakkee, Marjolein H. J. van Huijgevoort, and Ruud P. Bartholomeus
Hydrol. Earth Syst. Sci., 26, 551–569, https://doi.org/10.5194/hess-26-551-2022, https://doi.org/10.5194/hess-26-551-2022, 2022
Short summary
Short summary
Periods of drought often lead to groundwater shortages in large regions, which cause damage to nature and the economy. To take measures, we need a good understanding of where and when groundwater shortage occurs. In this study, we have tested a method that can combine large amounts of groundwater measurements in an automated way and provide detailed maps of how groundwater shortages develop during a drought period. This information can help water managers to limit future groundwater shortages.
Emmanuel Dubois, Marie Larocque, Sylvain Gagné, and Guillaume Meyzonnat
Hydrol. Earth Syst. Sci., 25, 6567–6589, https://doi.org/10.5194/hess-25-6567-2021, https://doi.org/10.5194/hess-25-6567-2021, 2021
Short summary
Short summary
This work demonstrates the relevance of using a water budget model to understand long-term transient and regional-scale groundwater recharge (GWR) in cold and humid climates where groundwater observations are scarce. Monthly GWR is simulated for 57 years on 500 m x 500 m cells in Canada (36 000 km2 area) with limited uncertainty due to a robust automatic calibration method. The increases in precipitation and temperature since the 1960s have not yet produced significant changes in annual GWR.
Yaniv Edery, Martin Stolar, Giovanni Porta, and Alberto Guadagnini
Hydrol. Earth Syst. Sci., 25, 5905–5915, https://doi.org/10.5194/hess-25-5905-2021, https://doi.org/10.5194/hess-25-5905-2021, 2021
Short summary
Short summary
The interplay between dissolution, precipitation and transport is widely encountered in porous media, from CO2 storage to cave formation in carbonate rocks. We show that dissolution occurs along preferential flow paths with high hydraulic conductivity, while precipitation occurs at locations close to yet separated from these flow paths, thus further funneling the flow and changing the probability density function of the transport, as measured on the altered conductivity field at various times.
Karina Y. Gutierrez-Jurado, Daniel Partington, and Margaret Shanafield
Hydrol. Earth Syst. Sci., 25, 4299–4317, https://doi.org/10.5194/hess-25-4299-2021, https://doi.org/10.5194/hess-25-4299-2021, 2021
Short summary
Short summary
Understanding the hydrologic cycle in semi-arid landscapes includes knowing the physical processes that govern where and why rivers flow and dry within a given catchment. To gain this understanding, we put together a conceptual model of what processes we think are important and then tested that model with numerical analysis. The results broadly confirmed our hypothesis that there are three distinct regions in our study catchment that contribute to streamflow generation in quite different ways.
Natascha Brandhorst, Daniel Erdal, and Insa Neuweiler
Hydrol. Earth Syst. Sci., 25, 4041–4059, https://doi.org/10.5194/hess-25-4041-2021, https://doi.org/10.5194/hess-25-4041-2021, 2021
Short summary
Short summary
We compare two approaches for coupling a 2D groundwater model with multiple 1D models for the unsaturated zone. One is non-iterative and very fast. The other one is iterative and involves a new way of treating the specific yield, which is crucial for obtaining a consistent solution in both model compartments. Tested on different scenarios, this new method turns out to be slower than the non-iterative approach but more accurate and still very efficient compared to fully integrated 3D model runs.
Vince P. Kaandorp, Hans Peter Broers, Ype van der Velde, Joachim Rozemeijer, and Perry G. B. de Louw
Hydrol. Earth Syst. Sci., 25, 3691–3711, https://doi.org/10.5194/hess-25-3691-2021, https://doi.org/10.5194/hess-25-3691-2021, 2021
Short summary
Short summary
We reconstructed historical and present-day tritium, chloride, and nitrate concentrations in stream water of a catchment using
land-use-based input curves and calculated travel times of groundwater. Parameters such as the unsaturated zone thickness, mean travel time, and input patterns determine time lags between inputs and in-stream concentrations. The timescale of the breakthrough of pollutants in streams is dependent on the location of pollution in a catchment.
Yueling Ma, Carsten Montzka, Bagher Bayat, and Stefan Kollet
Hydrol. Earth Syst. Sci., 25, 3555–3575, https://doi.org/10.5194/hess-25-3555-2021, https://doi.org/10.5194/hess-25-3555-2021, 2021
Short summary
Short summary
This study utilized spatiotemporally continuous precipitation anomaly (pra) and water table depth anomaly (wtda) data from integrated hydrologic simulation results over Europe in combination with Long Short-Term Memory (LSTM) networks to capture the time-varying and time-lagged relationship between pra and wtda in order to obtain reliable models to estimate wtda at the individual pixel level.
Raoul A. Collenteur, Mark Bakker, Gernot Klammler, and Steffen Birk
Hydrol. Earth Syst. Sci., 25, 2931–2949, https://doi.org/10.5194/hess-25-2931-2021, https://doi.org/10.5194/hess-25-2931-2021, 2021
Short summary
Short summary
This study explores the use of nonlinear transfer function noise (TFN) models to simulate groundwater levels and estimate groundwater recharge from observed groundwater levels. A nonlinear recharge model is implemented in a TFN model to compute the recharge. The estimated recharge rates are shown to be in good agreement with the recharge observed with a lysimeter present at the case study site in Austria. The method can be used to obtain groundwater recharge rates at
sub-yearly timescales.
Franci Gabrovšek and Wolfgang Dreybrodt
Hydrol. Earth Syst. Sci., 25, 2895–2913, https://doi.org/10.5194/hess-25-2895-2021, https://doi.org/10.5194/hess-25-2895-2021, 2021
Short summary
Short summary
The evolution of karst aquifers is often governed by solutions gaining their aggressiveness in depth. Although the principles of
hypogene speleogenesisare known, modelling studies based on reactive flow in fracture networks are missing. We present a model where dissolution at depth is triggered by the mixing of waters of different origin and chemistry. We show how the initial position of the mixing zone and flow instabilities therein determine the position and shape of the final conduits.
Patrick Morrissey, Paul Nolan, Ted McCormack, Paul Johnston, Owen Naughton, Saheba Bhatnagar, and Laurence Gill
Hydrol. Earth Syst. Sci., 25, 1923–1941, https://doi.org/10.5194/hess-25-1923-2021, https://doi.org/10.5194/hess-25-1923-2021, 2021
Short summary
Short summary
Lowland karst aquifers provide important wetland habitat resulting from seasonal flooding on the land surface. This flooding is controlled by surcharging of the karst system, which is very sensitive to changes in rainfall. This study investigates the predicted impacts of climate change on a lowland karst catchment in Ireland and highlights the relative vulnerability to future changing climate conditions of karst systems and any associated wetland habitats.
Liwen Wu, Jesus D. Gomez-Velez, Stefan Krause, Anders Wörman, Tanu Singh, Gunnar Nützmann, and Jörg Lewandowski
Hydrol. Earth Syst. Sci., 25, 1905–1921, https://doi.org/10.5194/hess-25-1905-2021, https://doi.org/10.5194/hess-25-1905-2021, 2021
Short summary
Short summary
With a physically based model that couples flow and heat transport in hyporheic zones, the present study provides the first insights into the dynamics of hyporheic responses to the impacts of daily groundwater withdrawal and river temperature fluctuations, allowing for a better understanding of transient hyporheic exchange processes and hence an improved pumping operational scheme.
Andreas Wunsch, Tanja Liesch, and Stefan Broda
Hydrol. Earth Syst. Sci., 25, 1671–1687, https://doi.org/10.5194/hess-25-1671-2021, https://doi.org/10.5194/hess-25-1671-2021, 2021
Jost Hellwig, Michael Stoelzle, and Kerstin Stahl
Hydrol. Earth Syst. Sci., 25, 1053–1068, https://doi.org/10.5194/hess-25-1053-2021, https://doi.org/10.5194/hess-25-1053-2021, 2021
Short summary
Short summary
Potential future groundwater and baseflow drought hazards depend on systems' sensitivity to altered recharge conditions. With three generic scenarios, we found different sensitivities across Germany driven by hydrogeology. While changes in drought hazard due to seasonal recharge shifts will be rather low, a lengthening of dry spells could cause stronger responses in regions with slow groundwater response to precipitation, urging local water management to prepare for more severe droughts.
Cited articles
Baudron, P., Alonso-Sarría, F., García-Aróstegui, J. L., Cánovas-García, F., Martínez-Vicente, D., and Moreno-Brotóns, J.: Identifying the origin of groundwater samples in a multi-layer aquifer system with Random Forest classification, J. Hydrol., 499, 303–315, https://doi.org/10.1016/j.jhydrol.2013.07.009, 2013.
Beck, H. E., Zimmermann, N. E., McVicar, T. R., Vergopolan, N., Berg, A., and Wood, E. F.: Present and future Köppen-Geiger climate classification maps at 1-km resolution, Sci. Data, 5, 180214, https://doi.org/10.1038/sdata.2018.214, 2018.
Berghuijs, W. R., Luijendijk, E., Moeck, C., van der Velde, Y., and Allen, S. T.: Global Recharge Data Set Indicates Strengthened Groundwater Connection to Surface Fluxes, Geophys. Res. Lett., 49, e2002GL099010, https://doi.org/10.1029/2022GL099010, 2022.
Bowen, B. B. and Benison, K. C.: Geochemical characteristics of naturally acid and alkaline saline lakes in southern Western Australia, Appl. Geochem., 24, 268–284, https://doi.org/10.1016/j.apgeochem.2008.11.013, 2009.
Broad, M.: Using Groundwater Age to Inform Aquifer Sustainability, Unpublished Honours Thesis, Flinders University, Adelaide, 2020.
Brunke, M. and Gonser, T. O. M.: The ecological significance of exchange processes between rivers and groundwater, Freshwater Biol., 37, 1–33, https://doi.org/10.1046/j.1365-2427.1997.00143.x, 1997.
Bureau of Meteorology: NDVI (Normalised Difference Vegetation Index) – High resolution gridded monthly NDVI dataset (1992 onwards), http://www.bom.gov.au/metadata/catalogue/19115/ANZCW0503900404 (last access: 12 January 2022), 2022a.
Bureau of Meteorology: Australian Groundwater Explorer, http://www.bom.gov.au/water/groundwater/explorer/map.shtml (last access: 9 June 2022), 2022b.
Bureau of Meteorology: Australian Water Outlook, https://awo.bom.gov.au/ (last access: 13 December 2022), 2022c.
Bureau of Meteorology: Climate classification maps – Seasonal rainfall – all zones, http://www.bom.gov.au/climate/maps/averages/climate-classification/?maptype=seasb (last access: 13 December 2022), 2022d.
Bureau of Meteorology: Decadal and multi-decadal rainfall averages maps, http://www.bom.gov.au/climate/maps/averages/decadal-rainfall/ (last access: 9 May 2023), 2023.
Cartwright, I., Weaver, T. R., Stone, D., and Reid, M.: Constraining modern and historical recharge from bore hydrographs, 3H, 14C, and chloride concentrations: Applications to dual-porosity aquifers in dryland salinity areas, Murray Basin, Australia, J. Hydrol., 332, 69–92, https://doi.org/10.1016/j.jhydrol.2006.06.034, 2007.
Cartwright, I., Cendón, D., Currell, M., and Meredith, K.: A review of radioactive isotopes and other residence time tracers in understanding groundwater recharge: Possibilities, challenges, and limitations, J. Hydrol., 555, 797–811, https://doi.org/10.1016/j.jhydrol.2017.10.053, 2017.
Cartwright, I., Morgenstern, U., Hofmann, H., and Gilfedder, B.: Comparisons and uncertainties of recharge estimates in a temperate alpine catchment, J. Hydrol., 590, 125558, https://doi.org/10.1016/j.jhydrol.2020.125558, 2020.
Crameri, F.: Scientific colour maps, Zenodo [data set], https://doi.org/10.5281/zenodo.1243862, 2018.
Crosbie, R. S., McCallum, J. L., and Harrington, G. A.: Diffuse groundwater recharge modelling across northern Australia. A report to the Australian Government from the CSIRO Northern Australia Sustainable Yields Project. CSIRO Water for a Healthy Country Flagship, Australia, 56 pp., https://publications.csiro.au/rpr/download?pid=changeme:394&dsid=DS1 (last access: 5 January 2024), 2009.
Crosbie, R., Jolly, I. D., Leaney, F. W., and Petheram, C.: Can the dataset of field based recharge estimates in Australia be used to predict recharge in data-poor areas?, Hydrol. Earth Syst. Sci., 14, 2023–2038, https://doi.org/10.5194/hess-14-2023-2010, 2010a.
Crosbie, R., Jolly, I., Leaney, F., Petheram, C., and Wohling, D.: Review of Australian groundwater recharge studies, CSIRO, 72 pp., https://doi.org/10.4225/08/58503a7f5aad4, 2010b.
Crosbie, R., Raiber, M., Wilkins, A., Dawes, W., Louth-Robins, T., and Gao, L.: Quantifying diffuse recharge to the Great Artesian Basin groundwater system, CSIRO, 52 pp., https://doi.org/10.25919/fwyj-cp80, 2022.
Crosbie, R. S. and Rachakonda, P. K.: Constraining probabilistic chloride mass-balance recharge estimates using baseflow and remotely sensed evapotranspiration: the Cambrian Limestone Aquifer in northern Australia, Hydrogeol. J., 29, 1399–1419, https://doi.org/10.1007/s10040-021-02323-1, 2021.
Crosbie, R. S., Peeters, L. J. M., Herron, N., McVicar, T. R., and Herr, A.: Estimating groundwater recharge and its associated uncertainty: Use of regression kriging and the chloride mass balance method, J. Hydrol., 561, 1063–1080, https://doi.org/10.1016/j.jhydrol.2017.08.003, 2018.
CSIRO: National Soil Grids – Australian Soil Classification, https://www.asris.csiro.au/themes/NationalGrids.html (last access: 21 June 2023), 2023.
Cuthbert, M. O., Acworth, R. I., Andersen, M. S., Larsen, J. R., McCallum, A. M., Rau, G. C., and Tellam, J. H.: Understanding and quantifying focused, indirect groundwater recharge from ephemeral streams using water table fluctuations, Water Resour. Res., 52, 827–840, https://doi.org/10.1002/2015WR017503, 2016.
Cutler, A., Cutler, D. R., and Stevens, J. R.: Random forests, in: Ensemble machine learning: Methods and applications, Springer, New York, NY, 157–175, https://doi.org/10.1007/978-1-4419-9326-7_5, 2012.
Davies, P. J. and Crosbie, R. S.: Mapping the spatial distribution of chloride deposition across Australia, J. Hydrol., 561, 76–88, https://doi.org/10.1016/j.jhydrol.2018.03.051, 2018.
de Graaf, I., Sutanudjaja, E. H., Van Beek, L. P. H., and Bierkens, M. F. P.: A high-resolution global-scale groundwater model, Hydrol. Earth Syst. Sci., 19, 823—837, https://doi.org/10.5194/hess-19-823-2015, 2015.
Department of Climate Change, Energy, the Environment and Water: Australia – Present Major Vegetation Groups – NVIS Version 6.0 (Albers 100 m analysis product), https://fed.dcceew.gov.au/maps/erin::australia-present-major-vegetation-groups-nvis-version-6-0 (last access: 12 January 2022), 2022.
de Vries, J. J. and Simmers, I.: Groundwater recharge: an overview of processes and challenges, Hydrogeol. J., 10, 5–17, https://doi.org/10.1007/s10040-001-0171-7, 2002.
Döll, P.: Vulnerability to the impact of climate change on renewable groundwater resources: a global-scale assessment, Environ. Res. Lett., 4, 035006, https://doi.org/10.1088/1748-9326/4/3/035006, 2009.
Döll, P. and Fiedler, K.: Global-scale modeling of groundwater recharge, Hydrol. Earth Syst. Sci., 12, 863–885, https://doi.org/10.5194/hess-12-863-2008, 2008.
Eamus, D.: Ecohydrology vegetation function, water and resource management, CSIRO Pub., Collingwood, Vic, 361 pp., https://doi.org/10.1071/9780643094093, 2006.
Eamus, D., Fu, B., Springer, A. E., and Stevens, L. E.: Groundwater Dependent Ecosystems: Classification, Identification Techniques and Threats, in: Integrated Groundwater Management: Concepts, Approaches and Challenges, edited by: Jakeman, A. J., Barreteau, O., Hunt, R. J., Rinaudo, J.-D., and Ross, A., Springer International Publishing, Cham, 313–346, https://doi.org/10.1007/978-3-319-23576-9_13, 2016.
Famiglietti, J. S.: The global groundwater crisis, Nat. Clim. Change, 4, 945–948, https://doi.org/10.1038/nclimate2425, 2014.
Fan, Y., Li, H., and Miguez-Macho, G.: Global patterns of groundwater table depth, Science, 339, 940–943, https://doi.org/10.1126/science.1229881, 2013.
FedUni: VVG – Visualising Victoria's Groundwater, https://www.vvg.org.au (last access: 20 August 2022), 2022.
Feitz, A. J., Tenthorey, E., and Coghlan, R. A.: Prospective hydrogen production regions of Australia, Geoscience Australia, 64 pp., https://doi.org/10.11636/Record.2019.015, 2019.
Ferguson, G., McIntosh, J. C., Jasechko, S., Kim, J.-H., Famiglietti, J. S., and McDonnell, J. J.: Groundwater deeper than 500 m contributes less than 0.1 % of global river discharge, Commun. Earth Environ., 4, 48, https://doi.org/10.1038/s43247-023-00697-6, 2023.
Frost, A. J. and Shokri, A.: The Australian Landscape Water Balance model (AWRA-L v7), Technical Report, Bureau of Meteorology, 58 pp., https://awo.bom.gov.au/assets/notes/publications/AWRA-Lv7_Model_Description_Report.pdf (last access: 21 September 2023), 2021.
Fu, G., Crosbie, R. S., Barron, O., Charles, S. P., Dawes, W., Shi, X., Van Niel, T., and Li, C.: Attributing variations of temporal and spatial groundwater recharge: A statistical analysis of climatic and non-climatic factors, J. Hydrol., 568, 816–834, https://doi.org/10.1016/j.jhydrol.2018.11.022, 2019.
Gallant, J. and Austin, J.: Slope derived from 1′′ SRTM DEM-S, v4, CSIRO, https://doi.org/10.4225/08/5689DA774564A, 2012.
Gallant, J., Wilson, N., Tickle, P. K., Dowling, T., and Read, A.: 3 second SRTM Derived Digital Elevation Model (DEM) Version 1.0, https://pid.geoscience.gov.au/dataset/ga/69888 (last access: 12 January 2022), 2009.
Gaur, M. K. and Squires, V. R.: Geographic extent and characteristics of the world's arid zones and their peoples, in: Climate variability impacts on land use and livelihoods in drylands, Springer, Cham, 3–20, https://doi.org/10.1007/978-3-319-56681-8_1, 2018.
Geoscience Australia: Geodata Coast 100K 2004, https://pid.geoscience.gov.au/dataset/ga/61395 (last access: 31 January 2022), 2004.
Geoscience Australia: Geoscience Australia Portal, https://portal.ga.gov.au/ (last access: 9 January 2022), 2022.
Gray, D. and Bardwell, N.: Hydrogeochemistry of New South Wales: Data Release, v1, CSIRO, https://doi.org/10.4225/08/5756B395C68B0, 2016a.
Gray, D. and Bardwell, N.: Hydrogeochemistry of Northern Territory: Data Release, v2, CSIRO, https://doi.org/10.4225/08/5987D4BA86FF7, 2016b.
Gray, D. and Bardwell, N.: Hydrogeochemistry of Queensland: Data Release, v1, CSIRO, https://doi.org/10.4225/08/575A453145914, 2016c.
Gray, D. and Bardwell, N.: Hydrogeochemistry of South Australia: Data Release, v1, CSIRO, https://doi.org/10.4225/08/5756B3BF09204, 2016d.
Gray, D. and Bardwell, N.: Hydrogeochemistry of Victoria: Data Release, v2, CSIRO, https://doi.org/10.4225/08/5987D4751859E, 2016e.
Gray, D. and Bardwell, N.: Hydrogeochemistry of Western Australia: Data Release, v1, CSIRO, https://doi.org/10.4225/08/575CDF378054A, 2016f.
Gray, D., Reid, N., Noble, R., and Giblin, A.: Hydrogeochemical Mapping of the Australian Continent, CSIRO, 109 pp., https://doi.org/10.25919/5d8bb939ef2f2, 2019.
Henne, A. and Reid, N.: Hydrogeochemistry of Tasmania: Data Release, v1, CSIRO, https://doi.org/10.25919/1P8B-G702, 2021.
Huang, X., Gao, L., Crosbie, R. S., Zhang, N., Fu, G., and Doble, R.: Groundwater Recharge Prediction Using Linear Regression, Multi-Layer Perception Network, and Deep Learning, Water, 11, 1879, https://doi.org/10.3390/w11091879, 2019.
Huang, X., Gao, L., Zhang, N., Crosbie, R. S., Ye, L., Liu, J., Guo, Z., Meng, Q., Fu, G., and Bryan, B. A.: A top-down deep learning model for predicting spatiotemporal dynamics of groundwater recharge, Environ. Model. Softw., 167, 105778, https://doi.org/10.1016/j.envsoft.2023.105778, 2023.
Irvine, D. J. and Cartwright, I.: CMBEAR: Python-Based Recharge Estimator Using the Chloride Mass Balance Method in Australia, Groundwater, 60, 418–425, https://doi.org/10.1111/gwat.13161, 2022.
King, A. C., Raiber, M., Cox, M. E., and Cendón, D. I.: Comparison of groundwater recharge estimation techniques in an alluvial aquifer system with an intermittent/ephemeral stream (Queensland, Australia), Hydrogeol. J., 25, 1759, https://doi.org/10.1007/s10040-017-1565-5, 2017.
Koch, J., Berger, H., Henriksen, H. J., and Sonnenborg, T. O.: Modelling of the shallow water table at high spatial resolution using random forests, Hydrol. Earth Syst. Sci., 23, 4603–4619, https://doi.org/10.5194/hess-23-4603-2019, 2019.
Leaney, F., Crosbie, R., O'Grady, A., Jolly, I., Gow, L., Davies, P., Wilford, J., and Kilgour, P.: Recharge and discharge estimation in data poor areas, Scientific reference guide, CSIRO, 70 pp., https://doi.org/10.4225/08/59b19769af701, 2011.
Lee, S.: A high-resolution map of diffuse groundwater recharge rates for Australia, HydroShare [code and data set], http://www.hydroshare.org/resource/5e7b8bfcc1514680902f8ff43cc254b8 (last access: 12 April 2024), 2024.
Lerner, D. N., Issar, A. S., and Simmers, I.: Groundwater recharge: A Guide to Understanding and Estimating Natural Recharge, International Contributions to Hydrogeology, 8, Verlag Heinz Heise, Germany, 345 pp., ISBN 392270591X, 1990.
MacDonald, A. M., Lark, R. M., Taylor, R. G., Abiye, T., Fallas, H. C., Favreau, G., Goni, I. B., Kebede, S., Scanlon, B., and Sorensen, J. P.: Mapping groundwater recharge in Africa from ground observations and implications for water security, Environ. Res. Lett., 16, 034012, https://doi.org/10.1088/1748-9326/abd661, 2021.
Malone, B. and Searle, R.: Soil and Landscape Grid National Soil Attribute Maps – Clay (3′′ resolution) – Release 2 (4), CSIRO, https://doi.org/10.25919/hc4s-3130, 2022a.
Malone, B. and Searle, R.: Soil and Landscape Grid National Soil Attribute Maps – Sand (3′′ resolution) – Release 2 (3), CSIRO, https://doi.org/10.25919/rjmy-pa10, 2022b.
Malone, B. and Searle, R.: Soil and Landscape Grid National Soil Attribute Maps – Silt (3′′ resolution) – Release 2, CSIRO, https://doi.org/10.25919/2ew1-0w57, 2022c.
Moeck, C., Grech-Cumbo, N., Podgorski, J., Bretzler, A., Gurdak, J. J., Berg, M., and Schirmer, M.: A global-scale dataset of direct natural groundwater recharge rates: A review of variables, processes and relationships, Sci. Total Environ., 717, 137042, https://doi.org/10.1016/j.scitotenv.2020.137042, 2020.
Mohan, C., Western, A. W., Wei, Y., and Saft, M.: Predicting groundwater recharge for varying land cover and climate conditions – a global meta-study, Hydrol. Earth Syst. Sci., 22, 2689–2703, https://doi.org/10.5194/hess-22-2689-2018, 2018.
Müller Schmied, H., Cáceres, D., Eisner, S., Flörke, M., Herbert, C., Niemann, C., Peiris, T. A., Popat, E., Portmann, F. T., and Reinecke, R.: The global water resources and use model WaterGAP v2.2d: Model description https://doi.org/10.5194/gmd-14-1037-2021, 2021.
National Land and Water Resources Audit: Australian dryland salinity assessment 2000: extent, impacts, processes, monitoring and management options, National Land & Water Resources Audit, Turner, ACT, 129 pp., ISBN 0642371067, 2001.
Ouedraogo, I., Defourny, P., and Vanclooster, M.: Validating a continental-scale groundwater diffuse pollution model using regional datasets, Environ. Sci. Pollut. Res., 26, 2105–2119, https://doi.org/10.1007/s11356-017-0899-9, 2019.
Pedregosa, F., Varoquaux, G., Gramfort, A., Michel, V., Thirion, B., Grisel, O., Blondel, M., Prettenhofer, P., Weiss, R., and Dubourg, V.: Scikit-learn: Machine learning in Python, J. Mach. Learn. Res., 12, 2825–2830, 2011.
Petheram, C., Walker, G., Grayson, R., Thierfelder, T., and Zhang, L.: Towards a framework for predicting impacts of land-use on recharge: 1. A review of recharge studies in Australia, Soil Res., 40, 397–417, https://doi.org/10.1071/SR00057, 2002.
Rahmati, O., Pourghasemi, H. R., and Melesse, A. M.: Application of GIS-based data driven random forest and maximum entropy models for groundwater potential mapping: a case study at Mehran Region, Iran, Catena, 137, 360–372, https://doi.org/10.1016/j.catena.2015.10.010, 2016.
Raymond, O. L., Liu, S., Gallagher, R., Zhang, W., and Highet, L. M.: Surface Geology of Australia 1:1 million scale dataset 2012 edition, Geoscience Australia, Canberra, https://doi.org/10.26186/74619, 2012.
Rodriguez-Galiano, V., Mendes, M. P., Garcia-Soldado, M. J., Chica-Olmo, M., and Ribeiro, L.: Predictive modeling of groundwater nitrate pollution using Random Forest and multisource variables related to intrinsic and specific vulnerability: A case study in an agricultural setting (Southern Spain), Sci. Total Environ., 476, 189–206, https://doi.org/10.1016/j.scitotenv.2014.01.001, 2014.
Scanlon, B. R., Healy, R. W., and Cook, P. G.: Choosing appropriate techniques for quantifying groundwater recharge, Hydrogeol. J., 10, 18–39, https://doi.org/10.1007/s10040-001-0176-2, 2002.
Scanlon, B. R., Keese, K. E., Flint, A. L., Flint, L. E., Gaye, C. B., Edmunds, W. M., and Simmers, I.: Global synthesis of groundwater recharge in semiarid and arid regions, Hydrol. Process., 20, 3335–3370, https://doi.org/10.1002/hyp.6335, 2006.
Shah, T.: Groundwater and human development: challenges and opportunities in livelihoods and environment, Water Sci. Technol., 51, 27–37, https://doi.org/10.2166/wst.2005.0217, 2005.
Sihag, P., Angelaki, A., and Chaplot, B.: Estimation of the recharging rate of groundwater using random forest technique, Appl. Water Sci., 10, 1–11, https://doi.org/10.1007/s13201-020-01267-3, 2020.
Strobl, C., Boulesteix, A.-L., Zeileis, A., and Hothorn, T.: Bias in random forest variable importance measures: Illustrations, sources and a solution, BMC Bioinform., 8, 1–21, https://doi.org/10.1186/1471-2105-8-25, 2007.
Toloşi, L. and Lengauer, T.: Classification with correlated features: unreliability of feature ranking and solutions, Bioinformatics, 27, 1986–1994, https://doi.org/10.1093/bioinformatics/btr300, 2011.
United Nations Environment Programme: World Atlas of Desertification, 2nd Edn., https://wedocs.unep.org/20.500.11822/30300 (last access: 17 January 2024), 1997.
Wada, Y., van Beek, L. P. H., van Kempen, C. M., Reckman, J. W. T. M., Vasak, S., and Bierkens, M. F. P.: Global depletion of groundwater resources, Geophys. Res. Lett., 37, L20402, https://doi.org/10.1029/2010GL044571, 2010.
Walker, D., Parkin, G., Schmitter, P., Gowing, J., Tilahun, S. A., Haile, A. T., and Yimam, A. Y.: Insights from a multi-method recharge estimation comparison study, Groundwater, 57, 245–258, https://doi.org/10.1111/gwat.12801, 2019.
West, C., Reinecke, R., Rosolem, R., MacDonald, A. M., Cuthbert, M. O., and Wagener, T.: Ground truthing global-scale model estimates of groundwater recharge across Africa, Sci. Total Environ., 858, 159765, https://doi.org/10.1016/j.scitotenv.2022.159765, 2023.
Wilford, J., Searle, R., Thomas, M., and Grundy, M.: Soil and Landscape Grid National Soil Attribute Maps – Depth of Regolith (3′′ resolution) – Release 2 (6), CSIRO, https://doi.org/10.4225/08/55C9472F05295, 2018.
Wilkins, A., Crosbie, R., Louth-Robins, T., Davies, P., Raiber, M., Dawes, W., and Gao, L.: Australian gridded chloride deposition-rate dataset, Data Brief, 42, 108189, https://doi.org/10.1016/j.dib.2022.108189, 2022.
Wood, W. W.: Use and Misuse of the Chloride-Mass Balance Method in Estimating Ground Water Recharge, Ground Water, 37, 2–3, https://doi.org/10.1111/j.1745-6584.1999.tb00949.x, 1999.
Short summary
Global groundwater recharge studies collate recharge values estimated using different methods that apply to different timescales. We develop a recharge prediction model, based solely on chloride, to produce a recharge map for Australia. We reveal that climate and vegetation have the most significant influence on recharge variability in Australia. Our recharge rates were lower than other models due to the long timescale of chloride in groundwater. Our method can similarly be applied globally.
Global groundwater recharge studies collate recharge values estimated using different methods...
