Preprints
Filtering by Subject: Hydrology
Representative elementary volumes, hysteresis and heterogeneity in multiphase flow from the pore to continuum scale
Published: 2019-09-22
Subjects: Earth Sciences, Engineering, Hydrology, Physical Sciences and Mathematics
Representative elementary volumes (REVs) and heterogeneity are key concepts in continuum multiphase flow, yet their manifestation from the pore-scale and associated impacts with the flow regime are not well understood. We use a multi-scale experimental and modelling approach to elucidate the role of REVs, hysteresis and heterogeneity in multiphase flow in two distinct water-wetting Bentheimer [...]
Global groundwater sustainability, resources and systems in the Anthropocene
Published: 2019-09-19
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Groundwater is a crucial resource for current and future generations but is not being sustainably used in many parts of the world. The objective of this review is to provide a clear portrait of global-scale groundwater sustainability, systems and resources in the Anthropocene, in order to inspire a pivot towards more sustainable pathways. We examine groundwater from three different but related [...]
The near-tip region of a hydraulic fracture with pressure-dependent leak-off and leak-in
Published: 2019-09-03
Subjects: Earth Sciences, Engineering, Environmental Sciences, Hydrology, Oil, Gas, and Energy, Physical Sciences and Mathematics, Volcanology
This paper is concerned with an analysis of the near tip region of a propagating fluid-driven fracture in a saturated permeable rock. The study attempts to accurately resolve the coupling between the physical processes - rock breakage, fluid pressure drop in the viscous fluid flow in the fracture, and fluid exchange between fracture and the rock - that exert influence on the hydraulic fracture [...]
Towards Improved Predictions in Ungauged Basins: Exploiting the Power of Machine Learning
Published: 2019-08-26
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Long Short-Term Memory (LSTM) networks offer unprecedented accuracy for prediction in ungauged basins. We trained and tested an LSTM on the CAMELS basins (approximately 30 years of daily rainfall/runoff data from 531 catchments in the US of sizes ranging from 4 km² to 2,000 km²) using k-fold validation, so that predictions were made in basins that supplied no training data. This effectively [...]
Variations in sub-daily precipitation at centennial scale
Published: 2019-08-15
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Short-term precipitation events with high intensities govern the dynamics of numerous fast hydrological processes like flash floods in urban areas and soil erosion in agriculture. It is expected that precipitation events will intensify as a consequence of climate change. Due to data availability long-term variations in precipitation rates are mostly studied based on daily precipitation recordings [...]
Spatial variation of groundwater response to multiple drivers in a depleting alluvial aquifer system, northwestern India
Published: 2019-08-12
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Unsustainable exploitation of groundwater in northwestern India has led to extreme but spatially variable depletion of the alluvial aquifer system in the region. Mitigation and management of groundwater resources require an understanding of the drivers behind the pattern and magnitude of groundwater depletion, but a regional perspective on these drivers has been lacking. The objectives of this [...]
Assessment of the community vulnerability to extreme spring floods: The case of the Amga River, central Yakutia, Siberia
Published: 2019-08-04
Subjects: Earth Sciences, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Spring floods in Sakha (Yakutia) Republic, Siberian Russia, annually induce a significant damage to the population and infrastructure of communities of this Arctic region. Most major urban settlements are protected from floods by dams and dikes, so rural areas take a heavy beat. In 2018, spring flooding severely hit numerous rural communities in the Amga River basin, central Yakutia, exposing [...]
Interannual, probabilistic prediction of water resources over Europe following the heatwave and drought 2018
Published: 2019-08-01
Subjects: Earth Sciences, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The year 2018 was one of the hottest and driest years in Europe having a large impact on agriculture, ecosystems and society. The associated drought in central and northern Europe underpins the need for water resources predictions at the seasonal to interannual time scale. In this study, we propose a probabilistic, terrestrial prediction system including water resources utilizing the Terrestrial [...]
Basal melting over Subglacial Lake Ellsworth and it catchment: insights from englacial layering
Published: 2019-07-25
Subjects: Earth Sciences, Geophysics and Seismology, Glaciology, Hydrology, Physical Sciences and Mathematics
Deep-water ‘stable’ subglacial lakes likely contain microbial life adapted in isolation to extreme environmental conditions. How water is supplied into a subglacial lake, and how water outflows, is important for understanding these conditions. Isochronal radio-echo layers have been used to infer where melting occurs above Lake Vostok and Lake Concordia in East Antarctica but have not been used [...]
Comment on Evaristo & McDonnell, Global analysis of streamflow response to forest management
Published: 2019-07-25
Subjects: Earth Sciences, Environmental Sciences, Forest Management, Forest Sciences, Hydrology, Life Sciences, Physical Sciences and Mathematics, Water Resource Management
Forests play a key role in the water cycle, so both planting and removing forests can affect streamflow. In a recent Nature article1, Evaristo and McDonnell used a gradient-boosted-tree model to conclude that streamflow response to forest removal is predominantly controlled by the potential water storage in the landscape, and that removing the worlds forests would contribute an additional 34,098 [...]
Evaluating precipitation datasets for large-scale distributed hydrological modelling
Published: 2019-07-18
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Over the past decades, a variety of valuable research studies has helped to advance our understanding of the advantages and limitations of satellite derived precipitation datasets as a forcing to hydrological models, in combination with or as an alternative to gauge data. However, most studies have assessed the performance of only one single dataset (or a few), have used global precipitation [...]
Pan-European groundwater to atmosphere terrestrial systems climatology from a physically consistent simulation
Published: 2019-07-18
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Applying the Terrestrial Systems Modeling Platform, TSMP, this study provides the first simulated long-term (1996-2018), high-resolution (~12.5km) terrestrial system climatology over Europe, which comprises variables from groundwater across the land surface to the top of the atmosphere (G2A). The data set offers an unprecedented opportunity to test hypotheses related to short- and long-range [...]
The Baltic TRANSCOAST approach – investigating shallow coasts as terrestrial-marine interface of water and matter fluxes
Published: 2019-07-16
Subjects: Biogeochemistry, Biology, Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Life Sciences, Marine Biology, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Other Plant Sciences, Physical Sciences and Mathematics, Plant Sciences, Soil Science
In Baltic TRANSCOAST we study the physical, biogeochemical, and biological processes at the land-ocean interface. The coastal zone is heavily impacted by various human activities as well as by geomorphological and climatic processes – on both the land and the sea side. Land-sea interactions at low lying coastal areas that are often dominated by peatlands, and are a common feature along the Baltic [...]
Increasing dependence of lowland population on mountain water resources
Published: 2019-06-28
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Mountain areas provide disproportionally high runoff in many parts of the world, but their importance for lowland water resources and food production has not been clarified so far. Here we quantify for the first time the extent to which lowland inhabitants potentially depend on runoff contributions from mountain areas (39% of land mass). We show that ~1.4 billion people (23% of world’s lowland [...]
Snow Depth and Snow Water Equivalent Estimation in the Northwestern Himalayan Watershed using Spaceborne Polarimetric SAR Interferometry
Published: 2019-06-27
Subjects: Earth Sciences, Engineering, Environmental Sciences, Hydrology, Physical Sciences and Mathematics, Water Resource Management
Snow depth (SD) and Snow Water Equivalent (SWE) constitute essential physical properties of snow and find extensive usage in the hydrological modelling domain. However, the prominent impact of the hydrometeorological conditions and difficult terrain conditions inhibit accurate measurement of the SD and SWE— an ongoing research problem in the cryosphere paradigm. In this context, spaceborne [...]