for Journals by Title or ISSN
for Articles by Keywords

Publisher: Elsevier   (Total: 3160 journals)

 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z  

        1 2 3 4 5 6 7 8 | Last   [Sort by number of followers]   [Restore default list]

Showing 1 - 200 of 3160 Journals sorted alphabetically
Academic Pediatrics     Hybrid Journal   (Followers: 37, SJR: 1.655, CiteScore: 2)
Academic Radiology     Hybrid Journal   (Followers: 25, SJR: 1.015, CiteScore: 2)
Accident Analysis & Prevention     Partially Free   (Followers: 97, SJR: 1.462, CiteScore: 3)
Accounting Forum     Hybrid Journal   (Followers: 28, SJR: 0.932, CiteScore: 2)
Accounting, Organizations and Society     Hybrid Journal   (Followers: 37, SJR: 1.771, CiteScore: 3)
Achievements in the Life Sciences     Open Access   (Followers: 5)
Acta Anaesthesiologica Taiwanica     Open Access   (Followers: 7)
Acta Astronautica     Hybrid Journal   (Followers: 427, SJR: 0.758, CiteScore: 2)
Acta Automatica Sinica     Full-text available via subscription   (Followers: 2)
Acta Biomaterialia     Hybrid Journal   (Followers: 28, SJR: 1.967, CiteScore: 7)
Acta Colombiana de Cuidado Intensivo     Full-text available via subscription   (Followers: 2)
Acta de Investigación Psicológica     Open Access   (Followers: 3)
Acta Ecologica Sinica     Open Access   (Followers: 10, SJR: 0.18, CiteScore: 1)
Acta Haematologica Polonica     Free   (Followers: 1, SJR: 0.128, CiteScore: 0)
Acta Histochemica     Hybrid Journal   (Followers: 3, SJR: 0.661, CiteScore: 2)
Acta Materialia     Hybrid Journal   (Followers: 288, SJR: 3.263, CiteScore: 6)
Acta Mathematica Scientia     Full-text available via subscription   (Followers: 6, SJR: 0.504, CiteScore: 1)
Acta Mechanica Solida Sinica     Full-text available via subscription   (Followers: 9, SJR: 0.542, CiteScore: 1)
Acta Oecologica     Hybrid Journal   (Followers: 12, SJR: 0.834, CiteScore: 2)
Acta Otorrinolaringologica (English Edition)     Full-text available via subscription  
Acta Otorrinolaringológica Española     Full-text available via subscription   (Followers: 2, SJR: 0.307, CiteScore: 0)
Acta Pharmaceutica Sinica B     Open Access   (Followers: 1, SJR: 1.793, CiteScore: 6)
Acta Poética     Open Access   (Followers: 4, SJR: 0.101, CiteScore: 0)
Acta Psychologica     Hybrid Journal   (Followers: 27, SJR: 1.331, CiteScore: 2)
Acta Sociológica     Open Access   (Followers: 1)
Acta Tropica     Hybrid Journal   (Followers: 6, SJR: 1.052, CiteScore: 2)
Acta Urológica Portuguesa     Open Access  
Actas Dermo-Sifiliograficas     Full-text available via subscription   (Followers: 3, SJR: 0.374, CiteScore: 1)
Actas Dermo-Sifiliográficas (English Edition)     Full-text available via subscription   (Followers: 2)
Actas Urológicas Españolas     Full-text available via subscription   (Followers: 3, SJR: 0.344, CiteScore: 1)
Actas Urológicas Españolas (English Edition)     Full-text available via subscription   (Followers: 1)
Actualites Pharmaceutiques     Full-text available via subscription   (Followers: 7, SJR: 0.19, CiteScore: 0)
Actualites Pharmaceutiques Hospitalieres     Full-text available via subscription   (Followers: 3)
Acupuncture and Related Therapies     Hybrid Journal   (Followers: 8)
Acute Pain     Full-text available via subscription   (Followers: 15, SJR: 2.671, CiteScore: 5)
Ad Hoc Networks     Hybrid Journal   (Followers: 11, SJR: 0.53, CiteScore: 4)
Addictive Behaviors     Hybrid Journal   (Followers: 17, SJR: 1.29, CiteScore: 3)
Addictive Behaviors Reports     Open Access   (Followers: 9, SJR: 0.755, CiteScore: 2)
Additive Manufacturing     Hybrid Journal   (Followers: 11, SJR: 2.611, CiteScore: 8)
Additives for Polymers     Full-text available via subscription   (Followers: 23)
Advanced Drug Delivery Reviews     Hybrid Journal   (Followers: 176, SJR: 4.09, CiteScore: 13)
Advanced Engineering Informatics     Hybrid Journal   (Followers: 12, SJR: 1.167, CiteScore: 4)
Advanced Powder Technology     Hybrid Journal   (Followers: 17, SJR: 0.694, CiteScore: 3)
Advances in Accounting     Hybrid Journal   (Followers: 9, SJR: 0.277, CiteScore: 1)
Advances in Agronomy     Full-text available via subscription   (Followers: 16, SJR: 2.384, CiteScore: 5)
Advances in Anesthesia     Full-text available via subscription   (Followers: 28, SJR: 0.126, CiteScore: 0)
Advances in Antiviral Drug Design     Full-text available via subscription   (Followers: 2)
Advances in Applied Mathematics     Full-text available via subscription   (Followers: 10, SJR: 0.992, CiteScore: 1)
Advances in Applied Mechanics     Full-text available via subscription   (Followers: 11, SJR: 1.551, CiteScore: 4)
Advances in Applied Microbiology     Full-text available via subscription   (Followers: 24, SJR: 2.089, CiteScore: 5)
Advances In Atomic, Molecular, and Optical Physics     Full-text available via subscription   (Followers: 14, SJR: 0.572, CiteScore: 2)
Advances in Biological Regulation     Hybrid Journal   (Followers: 4, SJR: 2.61, CiteScore: 7)
Advances in Botanical Research     Full-text available via subscription   (Followers: 2, SJR: 0.686, CiteScore: 2)
Advances in Cancer Research     Full-text available via subscription   (Followers: 32, SJR: 3.043, CiteScore: 6)
Advances in Carbohydrate Chemistry and Biochemistry     Full-text available via subscription   (Followers: 9, SJR: 1.453, CiteScore: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5, SJR: 1.992, CiteScore: 5)
Advances in Cell Aging and Gerontology     Full-text available via subscription   (Followers: 4)
Advances in Cellular and Molecular Biology of Membranes and Organelles     Full-text available via subscription   (Followers: 14)
Advances in Chemical Engineering     Full-text available via subscription   (Followers: 28, SJR: 0.156, CiteScore: 1)
Advances in Child Development and Behavior     Full-text available via subscription   (Followers: 10, SJR: 0.713, CiteScore: 1)
Advances in Chronic Kidney Disease     Full-text available via subscription   (Followers: 10, SJR: 1.316, CiteScore: 2)
Advances in Clinical Chemistry     Full-text available via subscription   (Followers: 26, SJR: 1.562, CiteScore: 3)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 20, SJR: 1.977, CiteScore: 8)
Advances in Computers     Full-text available via subscription   (Followers: 14, SJR: 0.205, CiteScore: 1)
Advances in Dermatology     Full-text available via subscription   (Followers: 15)
Advances in Developmental Biology     Full-text available via subscription   (Followers: 13)
Advances in Digestive Medicine     Open Access   (Followers: 11)
Advances in DNA Sequence-Specific Agents     Full-text available via subscription   (Followers: 7)
Advances in Drug Research     Full-text available via subscription   (Followers: 26)
Advances in Ecological Research     Full-text available via subscription   (Followers: 43, SJR: 2.524, CiteScore: 4)
Advances in Engineering Software     Hybrid Journal   (Followers: 29, SJR: 1.159, CiteScore: 4)
Advances in Experimental Biology     Full-text available via subscription   (Followers: 8)
Advances in Experimental Social Psychology     Full-text available via subscription   (Followers: 49, SJR: 5.39, CiteScore: 8)
Advances in Exploration Geophysics     Full-text available via subscription   (Followers: 1)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Food and Nutrition Research     Full-text available via subscription   (Followers: 61, SJR: 0.591, CiteScore: 2)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 17)
Advances in Genetics     Full-text available via subscription   (Followers: 20, SJR: 1.354, CiteScore: 4)
Advances in Genome Biology     Full-text available via subscription   (Followers: 10, SJR: 12.74, CiteScore: 13)
Advances in Geophysics     Full-text available via subscription   (Followers: 6, SJR: 1.193, CiteScore: 3)
Advances in Heat Transfer     Full-text available via subscription   (Followers: 24, SJR: 0.368, CiteScore: 1)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 12, SJR: 0.749, CiteScore: 3)
Advances in Human Factors/Ergonomics     Full-text available via subscription   (Followers: 23)
Advances in Imaging and Electron Physics     Full-text available via subscription   (Followers: 2, SJR: 0.193, CiteScore: 0)
Advances in Immunology     Full-text available via subscription   (Followers: 36, SJR: 4.433, CiteScore: 6)
Advances in Inorganic Chemistry     Full-text available via subscription   (Followers: 10, SJR: 1.163, CiteScore: 2)
Advances in Insect Physiology     Full-text available via subscription   (Followers: 2, SJR: 1.938, CiteScore: 3)
Advances in Integrative Medicine     Hybrid Journal   (Followers: 6, SJR: 0.176, CiteScore: 0)
Advances in Intl. Accounting     Full-text available via subscription   (Followers: 3)
Advances in Life Course Research     Hybrid Journal   (Followers: 8, SJR: 0.682, CiteScore: 2)
Advances in Lipobiology     Full-text available via subscription   (Followers: 1)
Advances in Magnetic and Optical Resonance     Full-text available via subscription   (Followers: 8)
Advances in Marine Biology     Full-text available via subscription   (Followers: 18, SJR: 0.88, CiteScore: 2)
Advances in Mathematics     Full-text available via subscription   (Followers: 11, SJR: 3.027, CiteScore: 2)
Advances in Medical Sciences     Hybrid Journal   (Followers: 7, SJR: 0.694, CiteScore: 2)
Advances in Medicinal Chemistry     Full-text available via subscription   (Followers: 5)
Advances in Microbial Physiology     Full-text available via subscription   (Followers: 4, SJR: 1.158, CiteScore: 3)
Advances in Molecular and Cell Biology     Full-text available via subscription   (Followers: 23)
Advances in Molecular and Cellular Endocrinology     Full-text available via subscription   (Followers: 8)
Advances in Molecular Toxicology     Full-text available via subscription   (Followers: 7, SJR: 0.182, CiteScore: 0)
Advances in Nanoporous Materials     Full-text available via subscription   (Followers: 4)
Advances in Oncobiology     Full-text available via subscription   (Followers: 2)
Advances in Organ Biology     Full-text available via subscription   (Followers: 2)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 17, SJR: 1.875, CiteScore: 4)
Advances in Parallel Computing     Full-text available via subscription   (Followers: 7, SJR: 0.174, CiteScore: 0)
Advances in Parasitology     Full-text available via subscription   (Followers: 5, SJR: 1.579, CiteScore: 4)
Advances in Pediatrics     Full-text available via subscription   (Followers: 25, SJR: 0.461, CiteScore: 1)
Advances in Pharmaceutical Sciences     Full-text available via subscription   (Followers: 12)
Advances in Pharmacology     Full-text available via subscription   (Followers: 16, SJR: 1.536, CiteScore: 3)
Advances in Physical Organic Chemistry     Full-text available via subscription   (Followers: 8, SJR: 0.574, CiteScore: 1)
Advances in Phytomedicine     Full-text available via subscription  
Advances in Planar Lipid Bilayers and Liposomes     Full-text available via subscription   (Followers: 3, SJR: 0.109, CiteScore: 1)
Advances in Plant Biochemistry and Molecular Biology     Full-text available via subscription   (Followers: 10)
Advances in Plant Pathology     Full-text available via subscription   (Followers: 5)
Advances in Porous Media     Full-text available via subscription   (Followers: 5)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20, SJR: 0.791, CiteScore: 2)
Advances in Psychology     Full-text available via subscription   (Followers: 66)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6, SJR: 0.371, CiteScore: 1)
Advances in Radiation Oncology     Open Access   (Followers: 1, SJR: 0.263, CiteScore: 1)
Advances in Small Animal Medicine and Surgery     Hybrid Journal   (Followers: 3, SJR: 0.101, CiteScore: 0)
Advances in Space Biology and Medicine     Full-text available via subscription   (Followers: 6)
Advances in Space Research     Full-text available via subscription   (Followers: 413, SJR: 0.569, CiteScore: 2)
Advances in Structural Biology     Full-text available via subscription   (Followers: 5)
Advances in Surgery     Full-text available via subscription   (Followers: 12, SJR: 0.555, CiteScore: 2)
Advances in the Study of Behavior     Full-text available via subscription   (Followers: 35, SJR: 2.208, CiteScore: 4)
Advances in Veterinary Medicine     Full-text available via subscription   (Followers: 19)
Advances in Veterinary Science and Comparative Medicine     Full-text available via subscription   (Followers: 15)
Advances in Virus Research     Full-text available via subscription   (Followers: 5, SJR: 2.262, CiteScore: 5)
Advances in Water Resources     Hybrid Journal   (Followers: 49, SJR: 1.551, CiteScore: 3)
Aeolian Research     Hybrid Journal   (Followers: 6, SJR: 1.117, CiteScore: 3)
Aerospace Science and Technology     Hybrid Journal   (Followers: 362, SJR: 0.796, CiteScore: 3)
AEU - Intl. J. of Electronics and Communications     Hybrid Journal   (Followers: 8, SJR: 0.42, CiteScore: 2)
African J. of Emergency Medicine     Open Access   (Followers: 6, SJR: 0.296, CiteScore: 0)
Ageing Research Reviews     Hybrid Journal   (Followers: 11, SJR: 3.671, CiteScore: 9)
Aggression and Violent Behavior     Hybrid Journal   (Followers: 470, SJR: 1.238, CiteScore: 3)
Agri Gene     Hybrid Journal   (Followers: 1, SJR: 0.13, CiteScore: 0)
Agricultural and Forest Meteorology     Hybrid Journal   (Followers: 17, SJR: 1.818, CiteScore: 5)
Agricultural Systems     Hybrid Journal   (Followers: 31, SJR: 1.156, CiteScore: 4)
Agricultural Water Management     Hybrid Journal   (Followers: 43, SJR: 1.272, CiteScore: 3)
Agriculture and Agricultural Science Procedia     Open Access   (Followers: 4)
Agriculture and Natural Resources     Open Access   (Followers: 3)
Agriculture, Ecosystems & Environment     Hybrid Journal   (Followers: 58, SJR: 1.747, CiteScore: 4)
Ain Shams Engineering J.     Open Access   (Followers: 5, SJR: 0.589, CiteScore: 3)
Air Medical J.     Hybrid Journal   (Followers: 6, SJR: 0.26, CiteScore: 0)
AKCE Intl. J. of Graphs and Combinatorics     Open Access   (SJR: 0.19, CiteScore: 0)
Alcohol     Hybrid Journal   (Followers: 12, SJR: 1.153, CiteScore: 3)
Alcoholism and Drug Addiction     Open Access   (Followers: 11)
Alergologia Polska : Polish J. of Allergology     Full-text available via subscription   (Followers: 1)
Alexandria Engineering J.     Open Access   (Followers: 2, SJR: 0.604, CiteScore: 3)
Alexandria J. of Medicine     Open Access   (Followers: 1, SJR: 0.191, CiteScore: 1)
Algal Research     Partially Free   (Followers: 11, SJR: 1.142, CiteScore: 4)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Allergologia et Immunopathologia     Full-text available via subscription   (Followers: 1, SJR: 0.504, CiteScore: 1)
Allergology Intl.     Open Access   (Followers: 5, SJR: 1.148, CiteScore: 2)
Alpha Omegan     Full-text available via subscription   (SJR: 3.521, CiteScore: 6)
ALTER - European J. of Disability Research / Revue Européenne de Recherche sur le Handicap     Full-text available via subscription   (Followers: 10, SJR: 0.201, CiteScore: 1)
Alzheimer's & Dementia     Hybrid Journal   (Followers: 52, SJR: 4.66, CiteScore: 10)
Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring     Open Access   (Followers: 4, SJR: 1.796, CiteScore: 4)
Alzheimer's & Dementia: Translational Research & Clinical Interventions     Open Access   (Followers: 4, SJR: 1.108, CiteScore: 3)
Ambulatory Pediatrics     Hybrid Journal   (Followers: 6)
American Heart J.     Hybrid Journal   (Followers: 57, SJR: 3.267, CiteScore: 4)
American J. of Cardiology     Hybrid Journal   (Followers: 62, SJR: 1.93, CiteScore: 3)
American J. of Emergency Medicine     Hybrid Journal   (Followers: 44, SJR: 0.604, CiteScore: 1)
American J. of Geriatric Pharmacotherapy     Full-text available via subscription   (Followers: 11)
American J. of Geriatric Psychiatry     Hybrid Journal   (Followers: 13, SJR: 1.524, CiteScore: 3)
American J. of Human Genetics     Hybrid Journal   (Followers: 34, SJR: 7.45, CiteScore: 8)
American J. of Infection Control     Hybrid Journal   (Followers: 29, SJR: 1.062, CiteScore: 2)
American J. of Kidney Diseases     Hybrid Journal   (Followers: 35, SJR: 2.973, CiteScore: 4)
American J. of Medicine     Hybrid Journal   (Followers: 48)
American J. of Medicine Supplements     Full-text available via subscription   (Followers: 3, SJR: 1.967, CiteScore: 2)
American J. of Obstetrics and Gynecology     Hybrid Journal   (Followers: 231, SJR: 2.7, CiteScore: 4)
American J. of Ophthalmology     Hybrid Journal   (Followers: 66, SJR: 3.184, CiteScore: 4)
American J. of Ophthalmology Case Reports     Open Access   (Followers: 5, SJR: 0.265, CiteScore: 0)
American J. of Orthodontics and Dentofacial Orthopedics     Full-text available via subscription   (Followers: 6, SJR: 1.289, CiteScore: 1)
American J. of Otolaryngology     Hybrid Journal   (Followers: 25, SJR: 0.59, CiteScore: 1)
American J. of Pathology     Hybrid Journal   (Followers: 29, SJR: 2.139, CiteScore: 4)
American J. of Preventive Medicine     Hybrid Journal   (Followers: 28, SJR: 2.164, CiteScore: 4)
American J. of Surgery     Hybrid Journal   (Followers: 39, SJR: 1.141, CiteScore: 2)
American J. of the Medical Sciences     Hybrid Journal   (Followers: 12, SJR: 0.767, CiteScore: 1)
Ampersand : An Intl. J. of General and Applied Linguistics     Open Access   (Followers: 7)
Anaerobe     Hybrid Journal   (Followers: 4, SJR: 1.144, CiteScore: 3)
Anaesthesia & Intensive Care Medicine     Full-text available via subscription   (Followers: 63, SJR: 0.138, CiteScore: 0)
Anaesthesia Critical Care & Pain Medicine     Full-text available via subscription   (Followers: 20, SJR: 0.411, CiteScore: 1)
Anales de Cirugia Vascular     Full-text available via subscription   (Followers: 1)
Anales de Pediatría     Full-text available via subscription   (Followers: 3, SJR: 0.277, CiteScore: 0)
Anales de Pediatría (English Edition)     Full-text available via subscription  
Anales de Pediatría Continuada     Full-text available via subscription  
Analytic Methods in Accident Research     Hybrid Journal   (Followers: 5, SJR: 4.849, CiteScore: 10)
Analytica Chimica Acta     Hybrid Journal   (Followers: 44, SJR: 1.512, CiteScore: 5)
Analytica Chimica Acta : X     Open Access  
Analytical Biochemistry     Hybrid Journal   (Followers: 200, SJR: 0.633, CiteScore: 2)
Analytical Chemistry Research     Open Access   (Followers: 12, SJR: 0.411, CiteScore: 2)
Analytical Spectroscopy Library     Full-text available via subscription   (Followers: 14)
Anesthésie & Réanimation     Full-text available via subscription   (Followers: 2)
Anesthesiology Clinics     Full-text available via subscription   (Followers: 23, SJR: 0.683, CiteScore: 2)
Angiología     Full-text available via subscription   (SJR: 0.121, CiteScore: 0)
Angiologia e Cirurgia Vascular     Open Access   (Followers: 1, SJR: 0.111, CiteScore: 0)
Animal Behaviour     Hybrid Journal   (Followers: 206, SJR: 1.58, CiteScore: 3)
Animal Feed Science and Technology     Hybrid Journal   (Followers: 6, SJR: 0.937, CiteScore: 2)

        1 2 3 4 5 6 7 8 | Last   [Sort by number of followers]   [Restore default list]

Similar Journals
Journal Cover
Advances in Water Resources
Journal Prestige (SJR): 1.551
Citation Impact (citeScore): 3
Number of Followers: 49  
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0309-1708
Published by Elsevier Homepage  [3160 journals]
  • Impact of climate change on European winter and summer flood losses
    • Abstract: Publication date: Available online 21 May 2019Source: Advances in Water ResourcesAuthor(s): Maximiliano Sassi, Ludovico Nicotina, Pardeep Pall, Dáithí Stone, Arno Hilberts, Michael Wehner, Stephen Jewson Climate change is expected to alter European floods and associated economic losses in various ways. Here we investigate the impact of precipitation change on European average winter and summer financial losses due to flooding under a 1.5°C warming scenario (reflecting a projected climate in the year 2115 according to RCP2.6) and for a counterfactual current-climate scenario where the climate has evolved without anthropogenic influence (reflecting a climate corresponding to pre-industrial conditions). Climate scenarios were generated with the Community Atmospheric Model (CAM) version 5. For each scenario, we derive a set of weights that when applied to the current climate's precipitation results in a climatology that approximates that of the scenario. We apply the weights to annual losses from a well-calibrated (to the current climate) flood loss model that spans 50,000 years and re-compute the average annual loss to assess the impact of precipitation changes induced by anthropogenic climate change. The method relies on a large stochastic set of physically based flood model simulations and allows quick assessment of potential loss changes due to change in precipitation based on two statistics, namely total precipitation, and total precipitation of very wet days (defined here as the total precipitation of days above the 95th percentile of daily precipitation). We compute the statistics with the raw CAM precipitation and bias-corrected precipitation. Our results show that for both raw and bias-corrected statistics i) average flood loss in Europe generally tend to increase in winter and decrease in summer for the future scenario, and consistent with that change we also show that ii) average flood losses have increased (decreased) for winter (summer) from pre-industrial conditions to the current day. The magnitude of the change varies among scenarios and statistics chosen.
  • The solution of the Riemann problem in rectangular channels with
           constrictions and obstructions
    • Abstract: Publication date: Available online 21 May 2019Source: Advances in Water ResourcesAuthor(s): Veronica Pepe, Luigi Cimorelli, Giovanni Pugliano, Renata Della Morte, Domenico Pianese, Luca Cozzolino Usually, the rapid geometric transitions that are of negligible length with respect to the channel are treated in one-dimensional Saint Venant models as internal boundary conditions, assuming that an instantaneous equilibrium is attained between the flow characteristics through the structure and the flow characteristics in the channel. In the present paper, a different point of view is assumed by considering rapid transients at channel constrictions and obstructions that are caused by the lack of instantaneous equilibrium between the flow conditions immediately upstream and downstream of the structure. These transients are modelled as a Riemann problem, assuming that the flow through the geometric transition is described by a stationary weak solution of the Saint Venant equations without friction. For this case, it is demonstrated that the solution of the Riemann problem exists and it is unique for a wide class of initial flow conditions, including supercritical flows. The solutions of the Riemann problem supplied by the one-dimensional mathematical model compare well with the results of a two-dimensional Shallow Water Equations numerical model when the head loss through the structure is negligible. The inspection of the exact solutions structure shows that the flow conditions immediately to the left and to the right of the geometric discontinuity may be very different from the initial conditions, and this contributes to explain the numerical issues that are reported in the literature for the rapid transients at internal boundary conditions in finite difference models. The solution of the Riemann problem has been coded, and the corresponding exact fluxes have been used as numerical fluxes in a one-dimensional Finite Volume scheme for the solution of the Shallow water Equations. The results demonstrate that spurious oscillations and instability phenomena are completely eliminated, ensuring the robustness of the approach. In the case that the energy loss is not negligible, the exact solutions capture the essential features of the two-dimensional model numerical results, ensuring that the mathematical procedure is generalizable to realistic conditions. This generalization is presented in the final part of the paper.
  • Floating treatment islands in series along a channel: the impact of island
           spacing on the velocity field and estimated mass removal.
    • Abstract: Publication date: Available online 18 May 2019Source: Advances in Water ResourcesAuthor(s): Chao Liu, Yuqi Shan, Jiarui Lei, Heidi Nepf Floating treatment islands (FTIs) consist of emergent vegetation grown on floating structures. The submerged roots beneath the island and the biofilm they support filter nutrients and particulates from water passing through the roots. FTIs are often deployed in series within a channel, but an optimum spacing between FTIs has not yet been determined. The goal of the present study is to identify an optimum spacing for maximum mass removal per channel length. A series of scaled FTI models were deployed in a water channel with the spacing between FTIs ranging from 0.5 to 11 times the length of an individual root zone. A Nortek Vectrino was used to measure the velocity field to determine the flow rate into and residence time within each root zone. The measured flow distribution was used within a control volume analysis to estimate the mass removed per channel length, assuming that removal within the root zone followed a first-order reaction. As the spacing between the FTIs decreased, the flow entering each FTI root zone also decreased, which decreased the mass removal of each individual FTI. However, as the spacing between FTIs was decreased, the number of FTIs per channel length increased, which tended to increase the mass removal of the system of FTI in series. These competing trends produced a maximum mass removal for FTIs spaced between one and three times the root zone length. The maximum spacing was weakly dependent on the assumed first-order reaction rate. The present study can help designers choose an optimal spacing for FTIs in series to achieve the maximum mass removal per river length.
  • From patch to channel scale: the evolution of emergent vegetation in a
    • Abstract: Publication date: Available online 18 May 2019Source: Advances in Water ResourcesAuthor(s): Taís N. Yamasaki, Paulo H.S. de Lima, Diego F. Silva, Cristiane G de A. Preza, Johannes G. Janzen, Heidi M. Nepf Computational fluid dynamics was used to study the evolution of small patches of vegetation into a vegetated landscape in a channel. The growth of new vegetation occurred in regions where the flow velocity was reduced below a threshold value defined as a fraction of the channel-average velocity (U0). Two threshold values, or limiting velocity values (LV), were used: LV = 0.5 and 0.7. Two initial blockage factors (percentage vegetation coverage of the channel) were considered, 3% and 0.3%, chosen to represent cases with and without, respectively, hydrodynamic interaction between the initial patches. The simulation illustrated both positive feedbacks between flow and vegetation, which enhanced vegetation expansion, and negative feedbacks, which led to patch erosion and limited patch growth. The most rapid expansion of the vegetated area occurred during the initial simulation steps, when the flow blockage due to vegetation was small. A higher velocity threshold (higher LV) produced more rapid initial growth and a higher final coverage of vegetation. The patches evolved to one or a few elongated islands extending along the channel.
  • An Extension of Darcy’s Law Incorporating Dynamic Length Scales
    • Abstract: Publication date: Available online 17 May 2019Source: Advances in Water ResourcesAuthor(s): Yuhang Wang, Saman A. Aryana, Myron B. Allen We propose a physics-based, macroscale formulation of multiphase porous-media flows that both honors the validity of Darcy’s law in steady or near-steady flows and accommodates the effects of heterogeneities and nonlinearities in unsteady flows. The new formulation recognizes that parameters characterizing the system operate at different length-scales. In particular, the use of Darcy’s law, predicated on the assumption of near-steady flows, requires dynamic length scales, owing to the possibility of rapid fluctuations in rock properties and fluid saturations attributable to heterogeneity and nonlinearity. We accommodate these dynamic length-scales through dynamic spatial averaging. The length and position of the averaging window are characterized by the length of the mixing zone and the direction of propagation of information in the transport process. We validate the proposed formulation by comparing highly accurate, two-dimensional numerical solutions against core-scale displacement experiments. The proposed paradigm is consistent with the classical multiphase Darcy formulation, in the sense that the latter also represents the results of an averaging approach.
  • Green-blue water accounting in a soil water balance
    • Abstract: Publication date: Available online 17 May 2019Source: Advances in Water ResourcesAuthor(s): Arjen Y. Hoekstra It has become common practice to speak about ‘green’ versus ‘blue’ water consumption, in order to distinguish between consumption of rainwater versus groundwater or surface water. The two sources of water differ in terms of possibilities for storage and use. Whereas industrial, municipal and livestock water supply primarily depend on blue water, crop cultivation relies on both green and blue water. Discriminating between green and blue water consumption in a crop field is not straightforward: consumption refers to evapotranspiration (ET) and water contained in the harvested crop, which both appear in undifferentiated form. One cannot see which part of ET or the water in a plant originates from rainwater and which part from irrigation water. In this paper I propose a generic and physically based method to differentiate green and blue evaporation (E) and green and blue transpiration (T) by daily accounting of the fractions green and blue water in each soil and vegetation layer. The green and blue fractions of all water fluxes leaving a soil or vegetation layer in a day depend on the average green and blue water fractions in that soil or vegetation layer during that day. This method allows for an accurate assessment of irrigation efficiency (the ratio of blue water transpiration to the irrigation water applied), and for a precise estimation of green and blue water footprints of crop production (the ratio of either green ET or blue ET to the crop yield).
  • A general Beerkan Estimation of Soil Transfer parameters method predicting
           hydraulic parameters of any unimodal water retention and hydraulic
           conductivity curves: application to the Kosugi soil hydraulic model
           without using particle size distribution data
    • Abstract: Publication date: Available online 16 May 2019Source: Advances in Water ResourcesAuthor(s): J. Fernández-Gálvez, J.A.P. Pollacco, L. Lassabatere, R. Angulo-Jaramillo, S. Carrick Soil hydraulic characterization is crucial to describe the retention and transport of water in soil, but current methodologies limit its spatial applicability. This paper presents a cost-effective general Beerkan Estimation of Soil Transfer parameters (BEST) methodology using single ring infiltration experiments to derive soil hydraulic parameters for any unimodal water retention and hydraulic conductivity functions. The proposed method relies on the BEST approach. The novelty lies in the use of Kosugi hydraulic parameters without need for textural information. In addition, the method uses a quasi-exact formulation that is valid for all times, which avoids the use of approximate expansions and related inaccuracy. The new BEST methods were tested against numerically generated data for several contrasting synthetic soils, and the results show that these methods provide consistent hydraulic functions close to the target functions. The new BEST method is accurate and can use any water retention and hydraulic conductivity functions.
  • Evaluation of Water Permeability of Rough Fractures Based on a Self-affine
           Fractal Model and Optimized Segmentation Algorithm
    • Abstract: Publication date: Available online 16 May 2019Source: Advances in Water ResourcesAuthor(s): Yang Ju, Jiabin Dong, Feng Gao, Jianguo Wang The water permeability of natural fractures is highly related to their morphological characteristics. For fractures with irregular profiles and variable apertures, it is challenging to define an appropriate aperture to apply the traditional cubic law for evaluating permeability. In this study, we propose a novel approach that integrates the standard deviation and the Hurst exponent of a self-affine fracture profile to characterise the effects of fracture morphology on permeability using Cuckoo search algorithms. A modified local cubic law was derived to evaluate permeability, considering the roughness and Hurst exponent of fractures. The required number of segments for a fracture was obtained by comparing simulation results using Lattice Boltzmann methods. The proposed permeability model and segment strategy were validated by experiments on rough fractures. The results show that the number of segments required for the model can be directly derived from the dimensionless aperture (i.e., mechanical aperture/length of fracture media).
  • Combining a land surface model with groundwater model calibration to
           assess the impacts of groundwater pumping in a mountainous desert basin
    • Abstract: Publication date: Available online 16 May 2019Source: Advances in Water ResourcesAuthor(s): Kuai Fang, Xinye Ji, Chaopeng Shen, Noel Ludwig, Peter Godfrey, Tasnuva Mahjabin, Christine Doughty The quantification of recharge and trans-valley underflow is needed in arid regions to estimate the impacts of new water withdrawals on the water table. However, for mountainous desert areas, such estimates are highly challenging, due to data scarcity, heterogeneous soils, and long residence times. Conventional assessment employs isolated groundwater models configured with simplified uniform estimates of recharge. Here, we employed a data-constrained surface-subsurface process model to provide an ensemble of spatially distributed recharge and underflow estimates using perturbed parameters. Then, the Model-Independent Parameter Estimation and Uncertainty Quantification (PEST) package was used to calibrate the aquifer hydraulic conductivity field in MODFLOW for this ensemble and reject implausible recharge values. This novel dual-model approach, broadly applicable to mountainous arid regions, was designed to maximally exploit available data sources. It can assimilate groundwater head observations, reject unrealistic parameters, and narrow the range of estimated drawdowns due to pumping. We applied this approach to the Chuckwalla basin in California, USA to determine natural recharge. Simulated recharge concentrates along alluvial fans at the mountain fronts and ephemeral washes where run-off water infiltrates. If an evenly distributed recharge was employed as in conventional studies, it would result in regional biases in estimated drawdown and larger uncertainty bounds. We also note that the speed of groundwater recovery does not guarantee sustainability: heavy pumping induces large hydraulic gradients that initially recover quickly when pumping is halted, but the system may not ultimately recover to pre-pumping levels.
  • Modeling subgrid-scale topographic effects on shallow marsh hydrodynamics
           and salinity transport
    • Abstract: Publication date: Available online 10 May 2019Source: Advances in Water ResourcesAuthor(s): Zhi Li, Ben R. Hodges A 2D depth-integrated subgrid hydrodynamic model (FrehdC) is designed to simulate effects of subgrid-scale topography on flow and scalar transport in shallow coastal marshes using computationally-efficient grid cells that are coarser than many of the channelized paths through the marsh. The subgrid-scale topography is parametrized into four depth-dependent variables (subgrid cell volume and three subgrid face areas) that characterize the high-resolution features of coarse grid cells. These variables are pre-stored in a table and embedded into the governing equations as model inputs to scale cell storage, mass and momentum fluxes across cell faces. A block-checking procedure is designed to automatically preserve high-resolution surface connectivity during grid-coarsening. By testing on both synthetic domain and real marshes, this new model is able to approximate fine-grid simulation results of surface elevation, inundation area, flow rate and salinity with less computational cost.
  • Unconditional and Conditional Solute Concentrations as Sampled in Natural
    • Abstract: Publication date: Available online 10 May 2019Source: Advances in Water ResourcesAuthor(s): Shayan Maleki, Virgilio Fiorotto The aim of this paper is to analyze the statistical properties of non-reactive solute concentrations in natural aquifers, taking into account the hydraulic conductivity heterogeneity. Quantifying the uncertainty in the evaluation of solute concentrations in aquifers is an important issue for human health and in ecological risk analysis. In particular, the concentration Cumulative Distribution Function (CDF) is a key element, as it informs the decision makers of the probability that the concentration at an environmental target is below a maximum contaminant level. The analysis presented in this paper is performed in a Lagrangian framework. According to the “reverse formulation”, the origin of the particle being sampled is sought instead of considering the destination of the injected particles. Based on this formulation, a closed form for the unconditioned concentration CDF is derived. The same procedure is applied to obtain a closed form for the concentration conditioned by measurements at sampling points in an aquifer.
  • Using a simple post-processor to predict residual uncertainty for multiple
           hydrological model outputs
    • Abstract: Publication date: Available online 8 May 2019Source: Advances in Water ResourcesAuthor(s): L.B. Ehlers, O. Wani, J. Koch, T.O. Sonnenborg, J.C. Refsgaard Regardless of the complexity of the hydrological model employed, uncertainty assessment (UA) is predominantly performed for the aggregated catchment response discharge. For coupled integrated models that simulate various hydrological states and fluxes on a grid cell basis, this represents a severe shortcoming. We test a simple data-driven technique (k-NN resampling) to evaluate its ability to provide reliable residual uncertainty estimates for the multi-variable (discharge, hydraulic head, soil moisture and actual evapotranspiration), deterministic output of two coupled groundwater-surface water models with different complexities. Being a nonparametric method, no explicit prior assumptions about the error distribution of different hydrological variables are required. When conditioning the algorithm, we propose to limit the number of error lags to be included based on inspection of the partial autocorrelation function (PACF). Our results confirm previous findings regarding reliability and robustness of the k-NN technique for discharge simulations and conclude that k-NN resampling also provides reliable and robust results for other variables like hydraulic head, soil moisture and actual evapotranspiration, even for underlying hydrological models with varying levels of performance. The 90 % prediction intervals (PI) capture the observations in the testing period satisfactorily for all hydrological variables (92.6–97.3 %), while Alpha indices (0.84–0.95) indicate very reliable PIs for all error quantiles. Differences in error structure between hydrological variables are successfully inferred from historical data and reflected in the results. We conclude that k-NN resampling represents a potent, cost-efficient UA technique for applications in operational hydrology, facilitating a near-simultaneous, easy uncertainty assessment for various outputs of computationally heavy hydrological models.
  • Pressure development in charged porous media with heterogeneous pore sizes
    • Abstract: Publication date: Available online 2 May 2019Source: Advances in Water ResourcesAuthor(s): P. Cornelissen, A. Leijnse, V. Joekar-Niasar, S.E.A.T.M. van der Zee Upscaling the microscopic processes in charged porous media which are responsible for pore pressure evolution and swelling is a topic of ongoing research. Current theories assume homogeneous media with uniform pore sizes and the impact of microscopic heterogeneity is neglected. This is a preliminary study to determine the significance of such pore-scale heterogeneity on the pressure evolution in charged porous media, where we neglect deformation of the solid phase. We present a pore-network model to simulate salt transport and pressure evolution in a charged porous medium. Results show that, for pore radii following a log-normal distribution, the average pressure in heterogeneous networks are significantly lower than in homogeneous networks with the same mean pore size. This is expressed by lower average pressures, as well as lower streaming potentials and faster ion transport rates in heterogeneous networks. These results indicate that heterogeneity in charged porous media should be investigated further.
  • (Multi)wavelets increase both accuracy and efficiency of standard
           Godunov-type hydrodynamic models
    • Abstract: Publication date: Available online 30 April 2019Source: Advances in Water ResourcesAuthor(s): Georges Kesserwani, James Shaw, Mohammad K Sharifian, Domenico Bau, Christopher J Keylock, Paul D Bates, Jennifer K Ryan This paper presents a scaled reformulation of a robust second-order Discontinuous Galerkin (DG2) solver for the Shallow Water Equations (SWE), with guiding principles on how it can be naturally extended to fit into the multiresolution analysis of multiwavelets (MW). Multiresolution analysis applied to the flow and topography data enables the creation of an adaptive MWDG2 solution on a non-uniform grid. The multiresolution analysis also permits control of the adaptive model error by a single user-prescribed parameter. This results in an adaptive MWDG2 solver that can fully exploit the local (de)compression of piecewise-linear modelled data, and from which a first-order finite volume version (FV1) is directly obtainable based on the Haar wavelet (HFV1) for local (de)compression of piecewise-constant modelled data. The behaviour of the adaptive HFV1 and MWDG2 solvers is systematically studied on a number of well-known hydraulic tests that cover all elementary aspects relevant to accurate, efficient and robust modelling. The adaptive solvers are run starting from a baseline mesh with a single element, and their accuracy and efficiency are measured referring to standard FV1 and DG2 simulations on the uniform grid involving the finest resolution accessible by the adaptive solvers. Our findings reveal that the MWDG2 solver can achieve the same accuracy as the DG2 solver but with a greater efficiency than the FV1 solver due to the smoothness of its piecewise-linear basis, which enables more aggressive coarsening than with the piecewise-constant basis in the HFV1 solver. This suggests a great potential for the MWDG2 solver to efficiently handle the depth and breadth in resolution variability, while also being a multiresolution mesh generator. Accompanying model software and simulation data are openly available online.
  • Changes in hydrodynamics and wave energy as a result of seagrass decline
           along the shoreline of a microtidal back-barrier estuary
    • Abstract: Publication date: Available online 30 April 2019Source: Advances in Water ResourcesAuthor(s): Carmine Donatelli, Neil K. Ganju, Tarandeep Singh Kalra, Sergio Fagherazzi, Nicoletta Leonardi Seagrasses are marine flowering plants that provide key ecological services. In recent decades, multiple stressors have caused a worldwide decline in seagrass beds. Changes in bottom friction associated with seagrass loss are expected to influence the ability of estuarine systems to trap sediment inputs through local and regional changes in hydrodynamics. Herein, we document a numerical study using six historical maps of seagrass distribution in Barnegat Bay, USA, to demonstrate that reductions in seagrass coverage destabilize estuarine systems, decreasing flood-dominance in areas affected by seagrass disappearance and increasing bed-shear stress values across the entire back-barrier basin. Furthermore, we reveal how seagrass decline has considerably increased the impact of wind-waves on marsh edges between 1968 and 2009. From a comparison with a numerical experiment without submerged aquatic vegetation, we estimate that up to 40% of the computed wave thrust on marsh boundaries can be reduced by seagrass beds and we find that the location of a seagrass patch in addition to its aerial extent plays a crucial role in this attenuation process. This study highlights the benefits of seagrass meadows in enhancing estuarine resilience and reducing marsh-edge retreat by wind-wave attack, which is recognized as a chief agent in lateral marsh loss.
  • Derivation of canonical total-sequences triggering landslides and
           floodings in complex terrain
    • Abstract: Publication date: Available online 26 April 2019Source: Advances in Water ResourcesAuthor(s): Katharina Enigl, Christoph Matulla, Matthias Schlögl, Franz Schmid Floodings and landslides are amongst the most devastating damage-processes worldwide. Associated risk levels are particularly high in topographically complex terrain. Along with the increase in climate-change induced extreme-events, research devoted to the identification of so-called Climate Indices (CIs) describing weather phenomena triggering hazard-occurrences and intensities gain rising emphasis.In this study we accomplish the first-time unification of the three most comprehensive cadastres on weather-induced hazard-processes, compiled and maintained by federal authorities. The therefrom resulting ‘event space’ stretches seven decades from 1950 onwards and contains more than 20.000 hazard occurrences, classified into different process-categories. Event data are analyzed together with a high-quality, daily-based dataset providing temperatures and precipitation totals on a 1 km grid across the Austrian part of the European Alps.On the resulting unprecedented extent of extreme-weather triggered hazard-processes and gridded weather observations we are able to examine the hypothesis that daily sequences of precipitation-totals preceding damage-events allow for detecting temporal weather sequences uniquely allocatable to various hazard-categories in three orographically distinct regions in the European Alps. We pursue this research aim by analyzing for each hazard-category its quadratic form representing the physics contained in the observations. Resulting eigen-directions, invariant under its inherent second order tensor, are the sought-for total-sequences (CIs) and hence reject the alternative hypothesis. Therefore, precipitation total-sequences can be uniquely assigned to hazard categories within each region.It is important to note that findings based on this novel, objective approach do not contradict, but rather add to attained research achievements by introducing this new perspective on the subject.Obtained CIs have substantial potential in research and applications. In civil defense, safeguarding critical infrastructure, early warning systems and the development of sustainable protection strategies, findings are in implementation by responsible decision-makers and in intense discussion with the European Freight and Logistics Leaders’ Forum.
  • Immiscible fluid displacement in porous media with spatially correlated
           particle sizes
    • Abstract: Publication date: Available online 26 April 2019Source: Advances in Water ResourcesAuthor(s): Oshri Borgman, Thomas Darwent, Enrico Segre, Lucas Goehring, Ran Holtzman Immiscible fluid displacement in porous media is fundamental for many environmental processes, including infiltration of water in soils, groundwater remediation, enhanced recovery of hydrocarbons and CO2 geosequestration. Microstructural heterogeneity, in particular of particle sizes, can significantly impact immiscible displacement. For instance, it may lead to unstable flow and preferential displacement patterns. We present a systematic, quantitative pore-scale study of the impact of spatial correlations in particle sizes on the drainage of a partially-wetting fluid. We perform pore-network simulations with varying flow rates and different degrees of spatial correlation, complemented with microfluidic experiments. Simulated and experimental displacement patterns show that spatial correlation leads to more preferential invasion, with reduced trapping of the defending fluid, especially at low flow rates. Numerically, we find that increasing the correlation length reduces the fluid-fluid interfacial area and the trapping of the defending fluid, and increases the invasion pattern asymmetry and selectivity. Our experiments, conducted for low capillary numbers, support these findings. Our results delineate the significant effect of spatial correlations on fluid displacement in porous media, of relevance to a wide range of natural and engineered processes.
  • Detecting inundation thresholds for dryland wetland vulnerability
    • Abstract: Publication date: Available online 25 April 2019Source: Advances in Water ResourcesAuthor(s): Steven G. Sandi, Patricia M. Saco, Neil Saintilan, Li Wen, Gerardo Riccardi, George Kuczera, Garry Willgoose, José F. Rodríguez Dryland wetlands receiving periodical floods are of key importance for ecological resilience. The inundation regime (i.e., frequency, duration, depth, and timing of inundation), is one of the major factors that determine the suitability of local conditions for specific wetland species. During droughts, inundation conditions can reach a threshold after which wetland vegetation could transition to dryland vegetation. This study analyses the response of vegetation to hydrologic variability in an arid wetland in Australia over a period of 22 years (including the Millennium drought) in order to identify inundation thresholds for transitions. We use numerical modelling, field observations and remote sensing data to relate continuous detailed simulations of the inundation regime with the response of patches of Common reed, Water couch and River red gum, three key vegetation associations in the study site. We focus in patches that were affected by the drought and presented dryland vegetation invasion as well as reference patches that remained healthy throughout the drought. On each patch, we compare annual and inter-annual simulated inundation regimes to the minimum inundation conditions that can support the specific vegetation, and we compute the percentage area of the patch that verifies minimum inundation for each year. We define this area percentage as minimum inundation index. This index is analysed in conjunction with Landsat derived information on green vegetation coverage (green Seasonal Fractional Cover) for the selected patches. We found that the minimum inundation index and inter annual frequency are able to describe the vegetation dynamics of the patches, which can be characterised by two distinct response modes that depend on a threshold value of the minimum inundation index. Inundation below the threshold noticeably leads to degraded vegetation, but the vegetation can recover quickly if this threshold is later maintained for one or two years. Values below the threshold for more extended periods (drought) result in a gradual decrease of wetland vegetation to almost complete disappearance after four years and subsequent dryland vegetation invasion.
  • Interplay of hyporheic exchange and fine particle deposition in a riverbed
    • Abstract: Publication date: Available online 24 April 2019Source: Advances in Water ResourcesAuthor(s): Guangqiu Jin, Yilin Chen, Hongwu Tang, Pei Zhang, Ling Li, D.A. Barry Hyporheic flow transports fine particles into the riverbed, which can lead to clogging of the bed and in turn affect hyporheic flow and exchange processes. Field measurements and numerical simulations show the formation of a low-permeability layer (LPL) near the bed surface due to fine particle clogging, and consequently reduction of exchange fluxes between the bed and river water. A characteristic porosity (ε*) and time scale were derived to quantify the clogging process and effects on transport. Both the exchange flux and mean solute residence time were found to follow a power law relationship with ε*. For the normalised particle exchange flux, the exponent is close to unity, i.e., a linear relationship with ε*. The results also showed significant effects of the fine particle concentration, pressure difference, sediment collision efficiency and fine particle diameter on the bed clogging. Large values of these parameters led to intensified clogging, with the formation of different types of LPL.
  • Mechanisms, configuration typology, and vulnerability of pumping-induced
           seawater intrusion in heterogeneous aquifers
    • Abstract: Publication date: Available online 24 April 2019Source: Advances in Water ResourcesAuthor(s): Xuan Yu, Holly A. Michael Coastal aquifers are vulnerable to seawater intrusion due to excessive groundwater pumping. Most research on salinization vulnerability considers homogeneous aquifers, forming the basis of management guidance. However, geologic structure can be highly heterogeneous, with preferential flow paths and low-permeability barriers that complicate flow and salt transport processes under pumping conditions. Here we use a series of variable-density groundwater flow and salt transport models with geostatistical representations of heterogeneity to illustrate characteristics of vulnerability in heterogeneous and homogeneous aquifers. Simulations showed that in homogeneous aquifers, salinization patterns were simple and related only to the hydraulic properties. In heterogeneous aquifers, salinization rates and patterns were much more complicated, and related to pumping location and depth, aquifer geometry, and geologic connections between pumping location, landward boundaries, and saline groundwater. An intrusion configuration typology approach was developed for both homogeneous and heterogeneous aquifers. The configuration approach was applied to heterogeneous aquifers of low, medium, and high geologic continuity, and vulnerability was assessed. The probability-based assessment was able to characterize the impact of pumping locations and rates in heterogeneous aquifers, considering different types of intrusion. The results showed that groundwater vulnerability to salinization was sensitive to pumping distance to the coastline for low-continuity aquifers and to pumping depth for high-continuity aquifers. The analysis provides new insights into the relationship between land-sea geologic connections and seawater intrusion vulnerability. The configuration approach plus probability-based assessment can be a starting point for large-scale aquifer characterization and more sophisticated groundwater management, including vulnerability assessment and optimization of pumping location, depth, and rate.
  • An argument-driven classification and comparison of reservoir operation
           optimization methods
    • Abstract: Publication date: Available online 18 April 2019Source: Advances in Water ResourcesAuthor(s): Barnaby Dobson, Thorsten Wagener, Francesca Pianosi Reservoir operation optimization aims to determine release and transfer decisions that maximise water management objectives such as ensuring a reliable water supply, hydropower production, mitigation of downstream floods, etc. An extensive and growing body of scientific literature exists on advancing and applying mathematical optimization methods to reservoir operation problems. In this paper, we review such literature according to a novel classification system of optimization approaches, which focuses on the characteristics of the actual operation problem – i.e. what needs to be optimized, or in mathematical terms, ‘the argument’ of the optimization problems - rather than the mathematical properties of the optimization algorithm. This enables us to discuss the advantages, limitations and the scope of application of the different optimisation methods; and to provide practical guidelines for matching the properties of a system and operation problem with a suitable optimization method. Alongside this paper we provide code to implement many of the methods we review for an illustrative reservoir system.Graphical abstractImage, graphical abstract
  • Multicomponent reactive transport modeling of effluent chemistry using
           locally obtained mineral dissolution rates of forsterite and pyrrhotite
           from a mine tailings deposit
    • Abstract: Publication date: Available online 16 April 2019Source: Advances in Water ResourcesAuthor(s): Rodrigo F. Embile, Ingar F. Walder, John J. Mahoney Multicomponent reactive transport modeling using PHREEQC of a Ni-sulfide tailings deposit was undertaken to assess how effective locally-obtained mineral dissolution rates in simulating long-term kinetic testing results of the tailings material. Forsterite and pyrrhotite were used as proxies for the chemical reactions occuring within the tailings. The dissolution rates of forsterite and pyrrhotite were obtained based on the actual kinetic testing data and PHREEQC inverse modeling. BET (Brunauer Emmet Teller) and geometric surface area-derived rates were used in the kinetic test data simulation and long-term prediction for 100 years. Results indicate that the geochemical models for both the BET and geometric surface area-derived rates are generally consistent with the actual pH, Mg, SO4 and Ni of the kinetic testing data. Long term prediction of effluent chemistry suggests that pH will continue to increase until a stable pH of 8 is achieved while the predicted Mg, SO4 and Ni concentrations will be stable and will be close to the concentrations observed towards the end of the kinetic test. This method of using locally-obtained mineral dissolution rates in multicomponent reactive transport modeling of a kinetic test data has proven to be reliable as compared to using literature dissolution rate values. This method can then be used for a quick and cost-effective way for future effluent chemistry prediction rather than conducting long and expensive kinetic tests.
  • Analytical Solution for Upscaling Hydraulic Conductivity in Anisotropic
           Heterogeneous Formations
    • Abstract: Publication date: Available online 16 April 2019Source: Advances in Water ResourcesAuthor(s): Qinzhuo Liao, Gang Lei, Dongxiao Zhang, Shirish Patil Modern geological modeling techniques represent anisotropic heterogeneous formations by high-resolution grids, which can be computationally prohibitive. This motivates the upscaling process that scales-up properties defined at a fine-scale system to equivalent properties defined at a coarse-scale system. In general, analytical methods are very efficient but limited to assumptions and approximations, whereas numerical methods are more robust albeit more time-consuming.In this work, we developed an analytical method to approximate numerical solutions in a finite difference scheme with periodic boundary conditions for two-dimensional problem. Using perturbation expansion techniques and Fourier analysis, the method generates explicit formulas of tensorial equivalent conductivity considering heterogeneity and anisotropy of two-dimensional space, as well as geometry of gridblocks. It is applicable for various cases with different covariance/variagram models and a wide range of log-conductivity variances, correlation lengths, rotation angles, anisotropy ratios of fine grid conductivity, anisotropy ratios of fine grid size, and the number of fine gridblocks in a coarse gridblock. The analytical method matched well with the numerical method for the estimation of the conductivity tensor, hydraulic head, and discharge velocity. The coefficients in the analytical method need to be computed only once for any given statistics, which makes the proposed method much more efficient than the numerical method.
  • Role of model parameterization in risk-based decision support: An
           empirical exploration
    • Abstract: Publication date: Available online 14 April 2019Source: Advances in Water ResourcesAuthor(s): Matthew J. Knowling, Jeremy T. White, Catherine R. Moore The degree with which to parameterize a computer model that is to be used for risk-based resource management decision support has been a topic of much discussion in the environmental modeling industry, and remains a difficult choice facing practitioners. High-dimensional parameterization schemes allow for a more robust expression of model input uncertainty over traditional lower-dimensional schemes, but often incur a higher computational burden and require greater understanding of inverse problem theory to implement effectively. However, a number of significant questions remain, such as: “What level of parameterization is needed to adequately express uncertainty for a given decision-relevant simulated output'”; and “To what extent can a simplified parameterization be adopted while maintaining the ability of the model to serve as a decision-support tool'”. This study addresses these questions, among others, by using empirical paired complex-simple model analyses to investigate the consequences of reduced parameterization on decision-relevant simulated outputs in terms of bias incursion and underestimation of uncertainty. A Bayesian decision analysis approach is adopted to facilitate evaluation of parameterization reduction outcomes, not only in terms of the prior and posterior probability density functions of decision-relevant simulated outputs, but also in terms of the management decisions that would be made on their basis. Two integrated surface water/groundwater model case study examples are presented; the first is a complex synthetic model used to forecast groundwater abstraction-induced changes in ecologically-sensitive streamflow characteristics, and the second is a real-world regional-scale model (Hauraki Plains, New Zealand) used to simulate nitrate-loading impacts on water quality. It is shown empirically that, for some decision-relevant simulated outputs, even relatively high-dimensional parameterization schemes ( > 2,000 adjustable parameters), display significant bias in simulated outputs as a result of improper parameter compensation induced through history matching, relative to complex parameterization cases ( > 100,000 adjustable parameters)—ultimately leading to incorrect decisions and resource management action. For other decision-relevant simulated outputs, however, reduced parameterization schemes may be appropriate for resource management decision making, especially when considering a prior uncertainty stance only.
  • Linking Statistical and Hydrodynamic Modeling for Compound Flood Hazard
           Assessment in Tidal Channels and Estuaries
    • Abstract: Publication date: Available online 12 April 2019Source: Advances in Water ResourcesAuthor(s): Hamed Moftakhari, Jochen E. Schubert, Amir AghaKouchak, Richard Matthew, Brett F. Sanders A method to link bivariate statistical analysis and hydrodynamic modeling for flood hazard estimation in tidal channels and estuaries is presented and discussed for the general case where flood hazards are linked to upstream riverine discharge Q and downstream ocean level, H. Using a bivariate approach, there are many possible combinations of Q and H that jointly reflect a specific return period, T, raising questions about the best choice as boundary forcing in a hydrodynamic model. We show, first of all, how possible Q and H values depend on whether the definition of T corresponds to the probability of exceedance of “H OR Q” or “H AND Q”. We also show that flood hazards defined by “OR” return periods are more conservative than “AND” return periods. Finally, we introduce a new composite water surface profile to represent the spatially distributed hazard for return period T. The composite profile synthesizes hydrodynamic model results from the “AND” hazard scenario and two scenarios based on traditional univariate analysis, a “Marginal Q” scenario and a “Marginal H” scenario.
  • Model-data fusion of hydrologic simulations and GRACE Terrestrial Water
           Storage observations to estimate changes in water table depth
    • Abstract: Publication date: Available online 10 April 2019Source: Advances in Water ResourcesAuthor(s): Dimitrios Stampoulis, John T. Reager, Cédric H. David, Konstantinos M. Andreadis, James S. Famiglietti, Tom G. Farr, Amy R. Trangsrud, Ralph R. Basilio, John L. Sabo, Gregory B. Osterman, Paul R. Lundgren, Zhen Liu Despite numerous advances in continental-scale hydrologic modeling and improvements in global Land Surface Models, an accurate representation of regional water table depth (WTD) remains a challenge. Data assimilation of observations from the Gravity Recovery and Climate Experiment (GRACE) mission leads to improvements in the accuracy of hydrologic models, ultimately resulting in more reliable estimates of lumped water storage. However, the usually shallow groundwater compartment of many models presents a problem with GRACE assimilation techniques, as these satellite observations also represent changes in deeper soils and aquifers. To improve the accuracy of modeled groundwater estimates and allow the representation of WTD at finer spatial scales, we implemented a simple, yet novel approach to integrate GRACE data, by augmenting the Variable Infiltration Capacity (VIC) hydrologic model. First, the subsurface model structural representation was modified by incorporating an additional (fourth) soil layer of varying depth (up to 1000 meters) in VIC as the bottom ‘groundwater’ layer. This addition allows the model to reproduce water storage variability not only in shallow soils but also in deeper groundwater, in order to allow integration of the full GRACE-observed variability. Second, a Direct Insertion scheme was developed that integrates the high temporal (daily) and spatial (∼6.94 km) resolution model outputs to match the GRACE resolution, performs the integration, and then disaggregates the updated model state after the assimilation step. Simulations were performed with and without Direct Insertion over the three largest river basins in California and including the Central Valley, in order to test the augmented model's ability to capture seasonal and inter-annual trends in the water table. This is the first-ever fusion of GRACE total water storage change observations with hydrologic simulations aiming at the determination of water table depth dynamics, at spatial scales potentially useful for local water management.
  • Pore Occupancy, Relative Permeability and Flow Intermittency Measurements
           Using X-Ray Micro-tomography in a Complex Carbonate
    • Abstract: Publication date: Available online 10 April 2019Source: Advances in Water ResourcesAuthor(s): Ying Gao, Ali Q. Raeini, Martin J. Blunt, Branko Bijeljic We imaged the steady-state flow of brine and decane (oil) at different fractional flows during dual injection in a micro-porous limestone, Estaillades, using X-ray micro-tomography. We applied differential imaging to (a) distinguish micro-porous regions from macro-pores, and (b) determine fluid pore occupancy in both regions, and relative permeability at a capillary number, Ca = 7.3 × 10−6. The sample porosity was approximately 28%, with 7% in macro-pores and 21% in pores that could not be directly resolved (micro-porosity). Fluid occupancy in micro-porosity was classified into three sub-phases: micro-pore space with oil, micro-pore space with brine, and micro-pores partially filled with oil and brine. Our method indicated an initially higher oil recovery from micro-porosity, consistent with waterflooding in a water-wet rock. The fractional flow and relative permeabilities of the two fluids were obtained from measurements of the pressure differential across the sample and the saturation calculated from the images. The brine saturation and relative permeabilities are impacted by the presence of water-wet micro-porosity which provides additional connectivity to the phases. Furthermore, we find that in addition to brine and decane, a fraction of the macroscopic pore space contains an intermittent phase, which is occupied either by brine or decane during the hour-long scan time. Pore and throat occupancy of oil, brine and intermittent phase were obtained from images at different fractional flows using the generalized pore network extracted from the image of macro-pores. The intermittent phase, where the occupancy fluctuated between oil-filled and brine-filled, was predominantly located in the small and intermediate size pores and throats. Overall, we establish a new experimental methodology to (i) quantify initial and recovered oil in micro-pores, (ii) characterise intermittent flow, and (iii) measure steady-state relative permeability in carbonates, which is shown to be greatly influenced by micro-porosity.
  • A double-continuum transport model for segregated porous media: derivation
           and sensitivity analysis-driven calibration
    • Abstract: Publication date: Available online 10 April 2019Source: Advances in Water ResourcesAuthor(s): G. Ceriotti, A. Russian, D. Bolster, G. Porta We derive a novel double-continuum transport model based on pore-scale characteristics. Our approach relies on building a simplified unit cell made up of immobile and mobile continua. We employ a numerically resolved pore-scale velocity distribution to characterize the volume of each continuum and to define the velocity profile in the mobile continuum. Using the simplified unit cell, we derive a closed form model, which includes two effective parameters that need to be estimated: a characteristic length scale and a parameter, RD, given by the ratio of characteristic times that lumps the effect of stagnant regions and escape process. To calibrate and validate our model, we rely on a set of pore-scale numerical simulation performed on a 2D disordered segregated periodic porous medium, taking into account different initial solute distributions. Using a Global Sensitivity Analysis, we explore the impact of the two effective parameters on solute concentration profiles and thereby define a Sensitivity Analysis driven criterion for model calibration. The latter is compared to a classical calibration approach. Our results show that, depending on the initial condition, the mass exchange process between mobile and immobile continua impact on solute profile shape significantly. Our transport model is capable of interpreting both symmetric and highly skewed solute concentration profiles. Effectiveness of the calibration of the two parameters largely depends on the content of information of calibration dataset and the selected objective function whose definition can be supported by the implementation of sensitivity analysis. By relying on a sensitivity analysis driven calibration, we are able to provide an accurate and robust interpretation of the concentration profile evolution across different given initial conditions by relying on a unique set of effective parameter values.
  • Solute transport in random composite media with uncertain dispersivities
    • Abstract: Publication date: Available online 9 April 2019Source: Advances in Water ResourcesAuthor(s): Aronne Dell'Oca, Monica Riva, Philippe Ackerer, Alberto Guadagnini Characterization of dissolved chemical migration in porous media requires knowledge of the fluid velocity field and parameters governing solute dispersion within the diverse geomaterials constituting the internal architecture of the system. Several studies have been focused on the assessment of the impact on solute concentrations of an incomplete knowledge of the fluid velocity field, typically a result of the effects of uncertain hydraulic properties of the hosting media (e.g., permeability). Limited attention has been devoted to analyze propagation of the uncertainty associated with spatial distributions of local dispersivity values to solute concentration fields. Here, we address this issue by focusing on a random composite medium, where the location of the boundary between two distinct geomaterials is uncertain as well as their associated dispersivity values. We derive and solve the equations satisfied by the (ensemble) mean and variance of solute concentration and investigate the relative impact on these moments of the two sources of uncertainty considered. Our results suggest that, in the investigated set-up, the temporal and spatial evolution of ensemble moments of the solute concentration depends on (i) the overall dispersive length scales encompassed by the solute during its migration and (ii) the actual sequence of the materials traversed by the solute.
  • A Forchheimer's law-based analytical model for constant-rate tests with
           linear flow pattern
    • Abstract: Publication date: Available online 9 April 2019Source: Advances in Water ResourcesAuthor(s): Yi-Feng Chen, Bo-Yong Li, Ming-Ming Liu, Ran Hu, Zhibing Yang Aquifers with quasi-linear flow pattern are frequently envisaged in fractured zones, in oil, gas or enhanced geothermal reservoirs, or in civil engineering where cut-off walls are constructed. The water flow towards a well in this linear aquifer system has been long investigated under Darcian flow condition, but remains an open issue for non-Darcian flow. In this study, a general linearization approximation strategy is suggested for the Forchheimer equation, and an analytical solution is proposed by using Laplace transform for non-Darcian flow towards a well in aquifers laterally bounded by no-flow barriers. Numerical simulations using the finite volume method prove that the linearization approximation performs best when it takes the mean of two commonly-used strategies, and the analytical model is sufficiently accurate at late times for observation wells located moderately far from the source. The proposed model was applied to data interpretation of the pumping tests at the Changheba dam foundation bounded by two cut-off walls in Southwest China, where the drawdown curves can be divided into 1D flow, transitional flow and 2D flow stages as a result of lateral flow through weathered bedrocks at late times. The proposed model provides a valuable tool for characterizing the hydraulic properties of aquifers and reservoirs with a linear flow pattern and for assessing the possible leakage through the lateral barriers by type curve matching.
  • Analysis of the influence of averaged positive second invariant Qav of
           deformation tensor ∇u on the maximum dilution index Emax in steady Darcy
           flows through isotropic heterogeneous porous media.
    • Abstract: Publication date: Available online 16 March 2019Source: Advances in Water ResourcesAuthor(s): Anthony Beaudoin, Arthur Dartois, Serge Huberson Characterization of flow topology is essential to understand the effects of the heterogeneity and dimensionality of geological formations on the mixing of inert solute clouds in these same geological formations. In this work, we numerically study two indicators of flow topology, the averaged vorticity magnitude ω av and the averaged positive second invariant Qav of the deformation tensor ∇u, in steady Darcy flows through exponentially correlated lognormal hydraulic conductivity fields K. Our numerical results allow us to establish the relationships between the two indicators considered here and the hydraulic conductivity variance σ2 in 2D and 3D, highlighting the role played by the spatial structure of these porous media on flow topology, and indirectly on mixing. This work leads us to assess the maximum dilution index Emax, indicator of mixing, theoretically known to increase monotonically in steady Darcy flows through isotropic heterogeneous porous media. Our numerical results allow us to test this hypothesis by establishing the relationship between the slope a of maximum dilution index Emax and the averaged positive second invariant Qav of deformation tensor ∇u. The parameters of this relationship depend on molecular diffusion and dimensionality of problem considered.
  • Impact of absorbing and reflective boundaries on fractional derivative
           models: Quantification, evaluation and application
    • Abstract: Publication date: Available online 27 February 2019Source: Advances in Water ResourcesAuthor(s): Yong Zhang, Xiangnan Yu, Xicheng Li, James F. Kelly, HongGuang Sun, Chunmiao Zheng Fractional-derivative models are promising tools for characterizing non-Fickian transport in heterogeneous media. Most fractional models utilize an infinite domain, although realistic problems occur on bounded domains. To quantify the impact of a finite or semi-infinite boundary on non-Fickian transport in natural geological media, this study evaluates three representative fractional advection-dispersion equations (FADEs) with absorbing or reflective boundaries. Results show that the temporal FADE (t-FADE) with absorbing/reflective boundaries has analytical solutions, the one-sided spatial FADE (s-FADE) in bounded-domains can be simulated using an Eulerian solver, and the tempered spatiotemporal FADE (st-FADE) can be efficiently solved using a fully Lagrangian approach. Further simulations reveal important impacts of absorbing/reflective boundaries on non-Fickian diffusion. First, the “local” reflective boundary mainly affects the solute dynamics near the boundary for non-local super-diffusion, while the “nonlocal” reflective boundary changes the overall pattern of non-Fickian transport in the whole domain. Second, the total mass for solutes in absorbing boundaries declines non-linearly with respect to time. Third, the mobile and immobile phase plumes tend to respond differently to the boundary because of their different transport mechanisms. Fourth, a field application shows that both the s-FADE with a negative skewness and the t-FADE can be used to quantify bounded-domain sub-diffusion for fluorescein dye transport in the Red Cedar River with a large Péclet number, although the determination of the upstream boundary position contains high uncertainty. Evaluation of the boundary impact on sub-diffusion, super-diffusion, and their mixture may improve our understanding of the nature of non-Fickian transport in bounded domains.
  • Corrigendum to “A new upscaling method for fractured porous media”
           [Advances in Water Resources 80 (2015): 60-68.]
    • Abstract: Publication date: Available online 11 January 2019Source: Advances in Water ResourcesAuthor(s): Tao Chen, Christoph Clauser, Gabriele Marquart, Karen Willbrand, Darius Mottaghy
  • The effects of cascade dam construction and operation on riparian
    • Abstract: Publication date: Available online 29 September 2018Source: Advances in Water ResourcesAuthor(s): Yu-jun Yi, Yang Zhou, Jie Song, Shanghong Zhang, Yanpeng Cai, Wei Yang, Zhifeng YangABSTRACTRiparian vegetation acts as a corridor, filter, or barrier for the flow of material, energy, and information between terrestrial and aquatic ecosystems. While, dam construction, especially cascade dam construction, bring huge changes to riparian vegetation. In this study, the changing of riparian vegetation cover in response to the construction and operation of large dams at different scale was analyzed. The variations of the normalized difference vegetation index (NDVI) in longitudinal and transverse directions during pre- and post-dam construction were calculated and analyzed. The results showed that dam height was the main determining factor for the range of riparian vegetation affected in the longitudinal direction, whereas valley contour and distance to dam site affect the transverse direction vegetation together. A linear or logarithmic relation between submerged area in transverse and the distance to dam were founded. After dam construction, the NDVI in the valley becomes uniform, and the vegetation grows more homogeneously. Influence extent of different elevation in different reaches was discussed. The intensive affected area including inundated area and 200m from the water surface in vertical direction. As the altitude grows, the influence gets weak. Positive effect of a single dam on vegetation in upstream reservoir was found except near channel grade, and a potential oligotrophic threat for the downstream vegetation was posted. For cascade dams, the vegetation in the upstream of Xiaowan dam became better from elevation 200-400m above original water surface. The NDVI between Xiaowan dam and Manwan dam, which at downstream of Xiaowan but in reservoir of Manwan, degraded after Xiaowan dam constructed. Cascade dams have cumulative effects on vegetation, the influence are positive or negative mainly depend on diversion of the dam.
  • Wave-induced morphodynamics and sediment transport around a slender
           vertical cylinder
    • Abstract: Publication date: Available online 13 February 2018Source: Advances in Water ResourcesAuthor(s): Massimo Miozzi, Sara Corvaro, Francisco Alves Pereira, Maurizio Brocchini We study the dynamics of a sandy bed around a slender vertical cylinder forced by progressive, non-linear water waves. The seabed evolves continuously under the effects of the up-welling, down-welling and rolling events induced by vortical coherent structures. In turn, these are closely connected to the shape of the seabed, which is modified by the scouring and/or the deposition of the sand. Starting from a flat seabed, progressive waves induce a rapid and transient modification of the bottom morphology towards a dynamically stable equilibrium state, which is the focus of this work. The dynamical equilibrium state is a function of the wave period and is reached when the seabed morphology is not substantially altered. We describe such a state by an Eulerian in-phase analysis of the sand particle motion, inferred from Lagrangian data collected over a large number of wave passages. This analysis relies on the use of the defocusing digital PIV technique (DDPIV), for the first time applied to the specific flow of interest here. On the basis of the Eulerian analysis, the triggering of the key-events (up- and down-welling, rolling) over the wave phase is captured by identifying, through the Q > 0 criterion, the coherent flow structures responsible for the events. This analysis is coupled with the description of the sediment trajectories, analyzed in a Lagrangian manner and effectively assessing how and where the solid phase is transported during the key-events. Five main mobilization/transport mechanisms have been identified, three during the onshore flow and two during the offshore flow: (i) generation of a coherent structure reminiscent of a horseshoe vortex at the toe, (ii) intense scouring at the top of the flatbed region, (iii) vortex shedding in the wake during direct (onshore) flow, (iv) shear crossflow on the lee-side of the cylinder and (v) large vertical shearing in the flatbed region during the reverse (offshore) flow. At flow reversal, this shearing mechanism impacts on a significant area of sediments in the incoming region of the flow.
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
Home (Search)
Subjects A-Z
Publishers A-Z
Your IP address:
About JournalTOCs
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-