Personal Research Database

Title: Journal of Hydro-Environment Research

Full Journal Title: Journal of Hydro-Environment Research

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: Impact Factor

Title: Journal of Hydrology

Full Journal Title: Journal of Hydrology

ISO Abbreviated Title: J. Hydrol.

JCR Abbreviated Title: J Hydrol

ISSN: 0022-1694

Issues/Year: 18

Journal Country/Territory: Netherlands

Language: Multi-Language

Publisher: Elsevier Science BV

Publisher Address: PO Box 211, 1000 AE Amsterdam, Netherlands

Subject Categories:

Engineering, Civil Geosciences, Interdisciplinary: Impact Factor 2.433, 3/106 (2009)

Geosciences, Multidisciplinary: Impact Factor 2.433, 29/155 (2009)

Water Resources: Impact Factor 2.433, 4/66 (2009)

Notes: highly cited

? Abbott, M.B., Bathurst, J.C., Cunge, J.A., Oconnell, P.E. and Rasmussen, J. (1986), An introduction to the european hydrological system - systeme hydrologique europeen, “SHE”. 1: History and philosophy of a physically-based, distributed modeling system. Journal of Hydrology, 87 (1-2), 45-59.

Full Text: 1986\J Hyd87, 45.pdf

Abstract: The paper forms the first part ot an introduction to the SHE, a physically-based, distributed, catchment modelling system produced jointly by the Danish Hydraulic Institute, the British Institute of Hydrology and SOGREAH (France) with the financial support of the Commission of the European Communities. The SHE developed from the perception that conventional rainfall/ runoff models are inappropriate to many pressing hydrological problems, especially those related to the impact of man’s activities on land-use change and water quality. Only through the use of models which have a physical basis and allow for spatial variations within a catchment can these problems be tackled. The physical basis and flexible operating structure of the SHE allows the model to use as many or as few data as are available and also to incorporate data on topography, vegetation and soil properties not normally included in catchment models. It does not require a lengthy hydrometeorological record for its calibration and its distributed nature enables the spatial variability in catchment inputs and outputs to be simulated. However, the large amount of data required by the model means that new operation methodologies must be evolved. Thus spatial scale effects or simply a lack of data may create significant uncertainties in the values of the catchment parameters used in a simulation. These uncertainties will give rise to corresponding uncertainties in the predictions. However, the SHE is able to quantify these uncertainties by carrying out sensitivity analyses for realistic ranges of the parameter values. Even when there is a lack of data, therefore, the SHE can act as a valuable “decision-support system”.

Notes: highly cited

? Beven, K. (1989), Changing ideas in hydrology - the case of physically-based models. Journal of Hydrology, 105 (1-2), 157-172.

Full Text: 1989\J Hyd105, 157.pdf

? Loague, K. (1990), Changing ideas in hydrology - the case of physically based models - Comment. Journal of Hydrology, 120 (1-4), 405-407.

Full Text: 1990\J Hyd120, 405.pdf

Everts, C.J. and Kanwar, R.S. (1994), Evaluation of rhodamine WT as an adsorbed tracer in an agricultural soil. Journal of Hydrology, 153 (1-4), 53-70.

Full Text: J\J Hyd153, 53.pdf

Abstract: Two column breakthrough tests and a series of 88 batch-equilibrium isotherms were conducted to quantify adsorption parameters for the fluorescent dye Rhodamine WT (Acid Red 388), in contact with a Nicollet loam soil. Results from batch-equilibrium isotherms performed at a 2: 1 (water: soil) ratio showed that dye adsorption reached an equilibrium after 10 min on a shaker table. Regression equations were developed to predict distribution coefficients (K(d)) for Rhodamine WT (RWT) adsorption to the soil based on soil organic carbon and the ionic strength of the RWT solution. A linear isotherm fitted the batch-equilibrium data for RWT in the concentration range evaluated (25-8000 g l^-1). K_d values obtained from the regression equation generated from the batch-equilibrium isotherms were input to a one-dimensional convection-dispersion model. The predicted results were compared with the experimental results obtained from two repacked column breakthrough curves. RWT adsorption was less than predicted in the first column (in which the breakthrough curve was terminated after 45 pore volumes), but greater than predicted for the second column (which was terminated after 420 pore volumes). The reason for the discrepancy was attributed to the plateau-shaped breakthrough curve observed for RWT and differences in the ionic compositions of the two RWT solutions used to conduct the two column breakthrough curves. RWT did not appear to be a reliable adsorbed tracer if quantitative prediction is needed. Breakthrough curves for atrazine and trifluralin, two herbicides present in the second column, showed atrazine adsorption to be less and trifluralin absorption greater as compared with RWT, as was predicted from their respective organic carbon partitioning coefficients (K(oc)).

Keywords: Water Residence Time, Fluorescent Dyes, Solute Uptake, Adsorption, Picloram, Sorption

Notes: highly cited

? Thornton, P.E., Running, S.W. and White, M.A. (1997), Generating surfaces of daily meteorological variables over large regions of complex terrain. Journal of Hydrology, 190 (3-4), 214-251.

Full Text: 1997\J Hyd190, 214.pdf

Abstract: A method for generating daily surfaces of temperature, precipitation, humidity, and radiation over large regions of complex terrain is presented. Required inputs include digital elevation data and observations of maximum temperature, minimum temperature and precipitation from ground-based meteorological stations. Our method is based on the spatial convolution of a truncated Gaussian weighting filter with the set of station locations. Sensitivity to the typical heterogeneous distribution of stations in complex terrain is accomplished with an iterative station density algorithm. Spatially and temporally explicit empirical analyses of the relationships of temperature and precipitation to elevation were performed, and the characteristic spatial and temporal scales of these relationships were explored. A daily precipitation occurrence algorithm is introduced, as a precursor to the prediction of daily precipitation amount. Surfaces of humidity (vapor pressure deficit) are generated as a function of the predicted daily minimum temperature and the predicted daily average daylight temperature. Daily surfaces of incident salar radiation are generated as a function of Sun-slope geometry and interpolated diurnal temperature range. The application of these methods is demonstrated over an area of approximately 400 000 km(2) in the northwestern USA, for 1 year, including a detailed illustration of the parameterization process. A cross-validation analysis was performed, comparing predicted and observed daily and annual average values. Mean absolute errors (MAE) for predicted annual average maximum and minimum temperature were 0.7 degrees C and 1.2 degrees C, with biases of +0.1 degrees C and -0.1 degrees C, respectively. MAE for predicted annual total precipitation was 13.4 cm, or, expressed as a percentage of the observed annual totals, 19.3%. The success rate for predictions of daily precipitation occurrence was 83.3%. Particular attention was given to the predicted and observed relationships between precipitation frequency and intensity, and they were shown to be similar. We tested the sensitivity of these methods to prediction grid-point spacing, and found that areal averages were unchanged for grids ranging in spacing from 500 m to 32 km. We tested the dependence of the results on timestep, and found that the temperature prediction algorithms scale perfectly in this respect. Temporal scaling of precipitation predictions was complicated by the daily occurrence predictions, but very nearly the same predictions were obtained at daily and annual timesteps. (C) 1997 Elsevier Science B.V.

Keywords: Forest Ecosystem Processes, Mountainous Terrain, Watershed Scale, Minimum Temperature, Climatic Gradient, Balance Model, Daily Maximum, Precipitation, Evapotranspiration, Hydrology

Notes: highly cited

? Hunter, K.S., Wang, Y.F. and Van Cappellen, P. (1998), Kinetic modeling of microbially-driven redox chemistry of subsurface environments: Coupling transport, microbial metabolism and geochemistry. Journal of Hydrology, 209 (1-4), 53-80.

Full Text: 1998\J Hyd209, 53.pdf

Abstract: This paper deals with the treatment of subsurface environments as reactive biogeochemical transport systems. We begin with an overview of the effects of microbial activity on the chemical dynamics in these environments. Then, after a review of earlier modeling efforts, we introduce a one-dimensional, multi-component reactive transport model that accounts for the reaction couplings among the major redox and acid-base elements, O, C, H, N, S, Mn, Fe and Ca. The model incorporates kinetic descriptions for the microbial degradation pathways of organic matter, as well as for the secondary redox reactions and mineral precipitation-dissolution reactions. Local equilibrium only applies to fast homogeneous speciation reactions and sorption processes. The model is used to simulate the distributions of chemical species and reaction rates along flow paths in two subsurface environments. In the first case, waters containing moderate levels of natural soil-derived organics supply a regional groundwater system. In the second case, a pristine aquifer is contaminated by an organic-rich leachate from a landfill. In both environments, the microbial oxidation of organic matter causes the disappearance of dissolved and solid oxidants and the appearance of reduced species, albeit over very different spatial scales. In the second case, a pronounced reaction front develops at the downstream edge of the contaminant plume. The reactivity, or biodegradability, of the organic matter is shown to be a major factor governing the biogeochemical dynamics in the plume. The simulations predict different distributions of the biodegradation pathways, depending on whether the organics of the leachate have uniform or variable reactivity. The secondary reactions also have a significant impact on the concentration profiles of inorganic species and the spatial distributions of the biodegradation pathways. Within the downstream reaction front, large fractions of O-2, Mn(IV), Fe(III) and SO₄^2- are reduced by secondary reactions, rather than being utilized in the oxidative degradation of leachate organics, overall, the model simulations emphasize the strong coupling between subsurface heterotrophic activity and an extensive network of secondary reactions. (C) 1998 Elsevier Science B.V. All rights reserved.

Keywords: Aerobic Aquifer, Aquitard Sediments, Biodegradable Organic Contaminants, Biodegradation Kinetics, Degradation, Equilibrium, In-Situ, Kinetic, Landfill Leachate, Manganese Reduction, Marine-Sediments, Microbial Activity, Multicomponent Reactive Transport, Reactive Transport, Redox Chemistry, Sorption, South-Carolina, Subsurface Environment, Sulfate Reduction

Notes: highly cited

? Goovaerts, P. (2000), Geostatistical approaches for incorporating elevation into the spatial interpolation of rainfall. Journal of Hydrology, 228 (1-2), 113-129.

Full Text: 2000\J Hyd228, 113.pdf

Abstract: This paper presents three multivariate geostatistical algorithms for incorporating a digital elevation model into the spatial prediction of rainfall: simple kriging with varying local means; kriging with an external drift; and colocated cokriging. The techniques are illustrated using annual and monthly rainfall observations measured at 36 climatic stations in a 5000 km(2) region of Portugal. Cross validation is used to compare the prediction performances of the three geostatistical interpolation algorithms with the straightforward linear regression of rainfall against elevation and three univariate techniques: the Thiessen polygon, inverse square distance; and ordinary kriging.

Larger prediction errors are obtained for the two algorithms (inverse square distance, Thiessen polygon) that ignore both the elevation and rainfall records at surrounding stations. The three multivariate geostatistical algorithms outperform other interpolators, in particular the linear regression, which stresses the importance of accounting for spatially dependent rainfall observations in addition to the colocated elevation. Last, ordinary kriging yields more accurate predictions than linear regression when the correlation between rainfall and elevation is moderate (less than 0.75 in the case study). (C) 2000 Elsevier Science B.V. All rights reserved.

Keywords: Rainfall, Dem, Multivariate Geostatistics, Kriging, Mountainous Terrain, Multivariate Geostatistics, Precipitation Estimation

Renssen, H. and Knoop, J.M. (2000), A global river routing network for use in hydrological modeling. Journal of Hydrology, 230 (3-4), 230-243.

Full Text: J\J Hyd230, 230.pdf

Abstract: In this paper a relatively simple procedure is presented to construct a global river routing network on a 0.5 degrees latitude-longitude grid. In this network all grid cells in a catchment are coupled and have a flow direction, making it a useful tool in the modeling of river flow on a global scale. The flow directions are based on a digital elevation model and on information on the locations of major rivers (‘stream burning’). The presented river routing network is specifically designed for the assessment of fresh water shortages. We tested the validity of the river routing network by comparing the computed drainage areas with published estimates. This comparison revealed a good similarity and it is concluded that the presented river routing network has sufficient quality to be implemented in global climate models. This could mean a considerable improvement of the surface parameterization in these models. (C) 2000 Elsevier Science B.V. All rights reserved.

Keywords: Runoff, Basin, Scale, Impact, World, GCM, Hydrology, Drainage Networks, Rivers and Streams, Data Processing, Runoff

Notes: highly cited

? Bates, P.D. and De Roo, A.P.J. (2000), A simple raster-based model for flood inundation simulation. Journal of Hydrology, 236 (1-2), 54-77.

Full Text: 2000\J Hyd236, 54.pdf

Abstract: In this paper the development of a new model for simulating flood inundation is outlined. The model is designed to operate with high-resolution raster Digital Elevation Models, which are becoming increasingly available for many lowland floodplain rivers and is based on what we hypothesise to the simplest possible process representation capable of simulating dynamic flood inundation. This consists of a one-dimensional kinematic wave approximation for channel flow solved using an explicit finite difference scheme and a two-dimensional diffusion wave representation of floodplain flow. The model is applied to a 35 km reach of the River Meuse in The Netherlands using only published data sources and used to simulate a large flood event that occurred in January 1995. This event was chosen as air photo and Synthetic Aperture Radar (SAR) data for flood inundation extent are available to enable rigorous validation of the developed model. 100, 50 and 25 m resolution models were constructed and compared to two other inundation prediction techniques: a planar approximation to the free surface and a relatively coarse resolution two-dimensional finite element scheme. The model developed in this paper outperforms both the simpler and more complex process representations, with the best fit simulation correctly predicting 81.9% of inundated and non-inundated areas. This compares with 69.5% for the best fit planar surface and 63.8% for the best fit finite element code. However, when applied solely to the 7 km of river below the upstream gauging station at Borgharen the planar model performs almost as well (83.7% correct) as the raster model (85.5% correct). This is due to the proximity of the gauge, which acts as a control point for construction of the planar surface and the fact that here low-lying areas of the floodplain an hydraulically connected to the channel. Importantly though it is impossible to generalise such application rules and thus we cannot specify a priori when the planar approximation will work. Simulations also indicate that, for this event at least, dynamic effects are relatively unimportant for prediction of peak inundation. Lastly, consideration of errors in typically available gauging station and inundation extent data shows the raster-based model to be close to the current prediction limit for this class of problem. (C) 2000 Elsevier Science B.V. All rights reserved.

Keywords: Floodplains, Floodplain Inundation, Hydraulic Modelling, Synthetic Aperture Radar, Compound Open-Channel, Flows

Notes: highly cited

? Beven, K. and Freer, J. (2001), Equifinality, data assimilation, and uncertainty estimation in mechanistic modelling of complex environmental systems using the GLUE methodology. Journal of Hydrology, 249 (1-4), 11-29.

Full Text: 2001\J Hyd249, 11.pdf

Abstract: It may be endemic to mechanistic modelling of complex environmental systems that there are many different model structures and many different parameter sets within a chosen model structure that may be behavioural or acceptable in reproducing the observed behaviour of that system. This has been called the equifinality concept. The generalised likelihood uncertainty estimation (GLUE) methodology for model identification allowing for equifinality is described. Prediction within this methodology is a process of ensemble forecasting using a sample of parameter sets from the behavioural model space, with each sample weighted according to its likelihood measure to estimate prediction quantiles. This allows that different models may contribute to the ensemble prediction interval at different time steps and that the distributional form of the predictions may change over time. Any effects of model nonlinearity, covariation of parameter values and errors in model structure, input data or observed variables, with which the simulations are compared, are handled implicitly within this procedure. GLUE involves a number of choices that must be made explicit and can be therefore subjected to scrutiny and discussion. These include ways of combining information from different types of model evaluation or from different periods in a data assimilation context. An example application to rainfall-runoff modelling is used to illustrate the methodology, including the updating of likelihood measures. (C) 2001 Elsevier Science B.V. All rights reserved.

Keywords: Bayesian-Estimation, Calibration, Catchments, Complex, Data Assimilation, Distributed Models, Elsevier, Equifinality, Evaluation, Forecasting, GLUE, Hydrology, Maimai Catchment, Model, Model Structure, Modelling, Models, Parameter Conditioning, Parameter Uncertainty, Prediction, Prediction Uncertainty, Predictions, Rainfall-Runoff, Rainfall-Runoff Modelling, Scale, Science, SVAT Model, System, Topmodel, Uncertainty, Uncertainty Estimation

Notes: highly cited

? Schaap, M.G., Leij, F.J. and van Genuchten, M.T. (2001), ROSETTA: A computer program for estimating soil hydraulic parameters with hierarchical pedotransfer functions. Journal of Hydrology, 251 (3-4), 163-176.

Full Text: 2001\J Hyd251, 163.pdf

Abstract: Soil hydraulic properties are necessary for many studies of water and solute transport but often cannot be measured because of practical and/or financial constraints. We describe a computer program, ROSETTA, which implements five hierarchical pedotransfer functions (PTFs) for the estimation of water retention, and the saturated and unsaturated hydraulic conductivity. The hierarchy in PTFs allows the estimation of van Genuchten water retention parameters and the saturated hydraulic conductivity using limited (textural classes only) to more extended (texture, bulk density, and one or two water retention points) input data. ROSETTA is based on neural network analyses combined with the bootstrap method, thus allowing the program to provide uncertainty estimates of the predicted hydraulic parameters. The general performance Of ROSETTA was characterized with coefficients of determination, and root mean square errors (RMSEs). The RMSE values decreased from 0.078 to 0.044 cm(3) cm(-3) for water retention when more predictors were used. The RMSE for the saturated conductivity similarly decreased from 0.739 to 0.647 (dimensionless log(10) units). The RMSE values for unsaturated conductivity ranged between 0.79 and 1.06, depending on whether measured or estimated retention parameters were used as predictors. Calculated mean errors showed that the PTFs underestimated water retention and the unsaturated hydraulic conductivity at relatively high suctions. ROSETTA’s uncertainty estimates can be used as an indication of model reliability when no hydraulic data are available. The ROSETTA program comes with a graphical user interface that allows user-friendly access to the PTFs, and can be downloaded from the US Salinity Laboratory website: http://www.ussl.ars.usda.gov/. (C) 2001 Elsevier Science B.V. All rights reserved.

Keywords: Soils, Hydraulic Conductivity, Retention, Neural Networks, Computer Programs, Particle-Size Distribution, Water-Retention Curves, Neural Networks, Bulk-Density, Conductivity, Model, Prediction, Texture

Jain, C.K. and Sharma, M.K. (2001), Distribution of trace metals in the Hindon River system, India. Journal of Hydrology, 253 (1-4), 81-90.

Full Text: J\J Hyd253, 81.pdf

Abstract: The distribution of trace metals (Cu, Zn, Fe, Mn, Cd, Cr, Pb, and Ni) in water, suspended and bed sediments of the River Hindon, a highly polluted river in western Uttar Pradesh (India) has been studied. The river is polluted by municipal, industrial and agricultural effluents, and flows through the city of Saharanpur, Muzaffarnagar and Ghaziabad districts. The heavy metal concentrations in water were observed to depend largely on the amount of flowing water and are negatively correlated with flow. Sediment analysis indicates that the large amount of heavy metals is associated with organic matter, the fine-grained sediment fraction and Fe/Mn hydrous oxides. A high positive correlation of most of the metal ions in sediments with iron, manganese and organic matter indicate that these constituents play a major role in transport of metal ions. The heavy metal concentrations generally increased with the decreasing particle size of the sediments. Lower metal concentrations in bed sediments during post-monsoon season established that monsoon had a slight effect on status of metals in sediments by causing renewal and mobilization of metals from the sediments. (C) 2001 Elsevier Science B.V. All rights reserved.

Keywords: Trace Metals, Distribution, Bed Sediments, River System, Chemical Mass-Balance, Heavy-Metals, Organic-Matter, Bed Sediments, Yamuna River, Ganges, Zinc, Lead, Contamination, Adsorption

Notes: highly cited

? Heberer, T. (2002), Tracking persistent pharmaceutical residues from municipal sewage to drinking water. Journal of Hydrology, 266 (3-4), 175-189.

Full Text: 2002\J Hyd266, 175.pdf

Abstract: In urban areas such as Berlin (Germany) with high municipal sewage water discharges and low surface water flows there is a potential risk of drinking water contamination by polar organic compounds when groundwater recharge is used in drinking water production. Thus, some pharmaceutically active compounds (PhACs) are not eliminated completely in the municipal sewage treatment plants (STPs) and they are discharged as contaminants into the receiving waters. In terms of several monitoring studies carried out in Berlin between 1996 and 2000, PhACs such as clofibric acid, diclofenac, ibuprofen, propyphenazone, primidone and carbamazepine were detected at individual concentrations up to the mu/I-level in influent and effluent samples from STPs and in all surface water samples collected downstream from the STPs. Under recharge conditions, several compounds were also found at individual concentrations up to 7.3 mug/I in samples collected from groundwater aquifers near to contaminated water courses. A few of the PhACs were also identified at the ng/I-level in Berlin tap water samples. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Pharmaceutically Active Compounds, Municipal Sewage, Persistent Drug Residues, Surface Water, Bank Filtration, Groundwater, Contamination, Drinking Water, Berlin Surface-Water, Treatment Plants, Organic Contaminants, Aquatic System, Estrogenic Chemicals, Mass-Spectrometry, Activated-Sludge, STW Effluent, Environment, Identification

Notes: highly cited

? Doll, P., Kaspar, F. and Lehner, B. (2003), A global hydrological model for deriving water availability indicators: Model tuning and validation. Journal of Hydrology, 270 (1-2), 105-134.

Full Text: 2003\J Hyd270, 105.pdf

Abstract: Freshwater availability has been recognized as a global issue, and its consistent quantification not only in individual river basins but also at the global scale is required to support the sustainable use of water. The WaterGAP Global Hydrology Model WGHM, which is a submodel of the global water use and availability model WaterGAP 2, computes surface runoff, groundwater recharge and river discharge at a spatial resolution of 0.5degrees. WGHM is based on the best global data sets currently available, and simulates the reduction of river discharge by human water consumption. In order to obtain a reliable estimate of water availability, it is tuned against observed discharge at 724 gauging stations, which represent 50% of the global land area and 70% of the actively discharging area. For 50% of these stations, the tuning of one model parameter was sufficient to achieve that simulated and observed long-term average discharges agree within 1%. For the rest, however, additional corrections had to be applied to the simulated runoff and discharge values. WGHM not only computes the long-term average water resources of a country or a drainage basin but also water availability indicators that take into account the interannual and seasonal variability of runoff and discharge. The reliability of the modeling results is assessed by comparing observed and simulated discharges at the tuning stations and at selected other stations. The comparison shows that WGHM is able to calculate reliable and meaningful indicators of water availability at a high spatial resolution. In particular, the 90% reliable monthly discharge is simulated well. Therefore, WGHM is suited for application in global assessments related to water security, food security and freshwater ecosystems. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords: Hydrology, Global Model, Discharge, Runoff, Water Availability, Model Tuning, Variability, Balance, Climate, Runoff, World

Notes: highly cited

? Simunek, J., Jarvis, N.J., van Genuchten, M.T. and Gardenas, A. (2003), Review and comparison of models for describing non-equilibrium and preferential flow and transport in the vadose zone. Journal of Hydrology, 272 (1-4), 14-35.

Full Text: 2003\J Hyd272, 14.pdf

Abstract: In this paper, we review various approaches for modeling preferential and non-equilibrium flow and transport in the vadose zone. Existing approaches differ in terms of their underlying assumptions and complexity. They range from relatively simplistic models to more complex physically based dual-porosity, dual-permeability, and multi-region type models. A relatively simple dual-porosity flow model results when the Richards equation is combined with composite (double-hump type) equations for the hydraulic properties to account for both soil textural (matrix) and soil structural (fractures, macropores, peds) effects on flow. The simplest non-equilibrium flow model, a single-porosity model which distinguishes between actual and equilibrium water contents, is based on a formulation by Ross and Smettem [Soil Sci. Soc. Am. J. 64 (2000) 1926] that requires only one additional parameter to account for non-equilibrium. A more complex dual-porosity, mobile-immobile water flow model results when the Richards or kinematic wave equations are used for flow in the fractures, and immobile water is assumed to exist in the matrix. We also discuss various dual-permeability models, including the formulation of Gerke and van Genuchten [Water Resour. Res. 29 (1993a) 305] and the kinematic wave approach as used in the MACRO model of Jarvis [Technical Description and Sample Simulations, Department of Soil Science, Swedish University of Agricultural Science, Uppsala, Sweden (1994) 51]. Both of these models invoke terms accounting for the exchange of water and solutes between the matrix and the fractures. Advantages and disadvantages of the different models are discussed, and the need for inter-code comparison is stressed, especially against field data that are sufficiently comprehensive to allow calibration/validation of the more complex models and to distinguish between alternative modeling concepts. Several examples and comparisons of equilibrium and various non-equilibrium flow and transport models are also provided. Published by Elsevier Science B.V.

Keywords: Preferential Flow, Non-Equilibrium Flow, Vadose Zone, Dual-Porosity Models, Dual-Permeability Models, Solute Transport, Pedon Scale, Dual-Porosity Model, Nonequilibrium Water-Flow, Soil Hydraulic-Properties, Fracture Matrix Flow, Porous-Media, Solute Transport, Unsaturated Soil, Irrigated Field, Macropore Flow, Mass-Transfer

Notes: highly cited

? Hock, R. (2003), Temperature index melt modelling in mountain areas. Journal of Hydrology, 282 (1-4), 104-115.

Full Text: 2003\J Hyd282, 104.pdf

Abstract: Temperature index or degree-day models rest upon a claimed relationship between snow or ice melt and air temperature usually expressed in the form of positive temperatures. Since air temperature generally is the most readily available data, such models have been the most widely used method of ice and snow melt computations for many purposes, such as hydrological modelling, ice dynamic modelling or climate sensitivity studies. Despite their simplicity, temperature-index models have proven to be powerful tools for melt modelling, often on a catchment scale outperforming energy balance models. However, two shortcomings are evident: (1) although working well over long time periods their accuracy decreases with increasing temporal resolution; (2) spatial variability cannot be modelled accurately as melt rates may vary substantially due to topographic effects such as shading, slope and aspect angles. These effects are particularly crucial in mountain areas. This paper provides an overview of temperature-index methods, including glacier environments, and discusses recent advances on distributed approaches attempting to account for topographic effects in complex terrain, while retaining scarcity of data input. In the light of an increasing demand for melt estimates with high spatial and temporal resolution, such approaches need further refinement and development. (C) 2003 Elsevier B.V. All rights reserved.

Keywords: Temperature Index Models, Degree-Day Factor, Melt Modelling, Glacier Mass Balance, Snowmelt Runoff Model, Glacier Mass-Balance, Greenland Ice-Sheet, West Greenland, Energy-Balance, Climate-Change, Heat-Balance, Ablation, Sensitivity, Radiation

Notes: highly cited

? Gerten, D., Schaphoff, S., Haberlandt, U., Lucht, W. and Sitch, S. (2004), Terrestrial vegetation and water balance - hydrological evaluation of a dynamic global vegetation model. Journal of Hydrology, 286 (1-4), 249-270.

Full Text: 2004\J Hyd286, 249.pdf

Abstract: Earth’s vegetation plays a pivotal role in the global water balance. Hence, there is a need to model dynamic interactions and feedbacks between the terrestrial biosphere and the water cycle. Here, the hydrological performance of the Lund-Potsdam-Jena model (LPJ), a prominent dynamic global vegetation model, is evaluated. Models of this type simulate the coupled terrestrial carbon and water cycle, thus they are well suited for investigating biosphere-hydrosphere interactions over large domains. We demonstrate that runoff and evapotranspiration computed by LPJ agree well with respective results from state-of-the-art global hydrological models, while in some regions, runoff is significantly over- or underestimated compared to observations. The direction and magnitude of these biases is largely similar to those from other macro-scale models, rather than specific to LPJ. They are attributable primarily to uncertainties in the climate input data, and to human interventions not considered by the model (e.g. water withdrawal, land cover conversions). Additional model development is required to perform integrated assessments of water exchanges among the biosphere, the hydrosphere, and the anthroposphere. Yet, the LPJ model can now be used to study inter-relations between the world’s major vegetation types and the terrestrial water balance. As an example, it is shown that a doubling of atmospheric CO2 content alone would result in pronounced changes in evapotranspiration and runoff for many parts of the world. Although significant, these changes would remain unseen by stand-alone hydrological models, thereby emphasizing the importance of simulating the coupled carbon and water cycle. (C) 2003 Elsevier B.V. All rights reserved.

Keywords: Macro-Scale Models, Global Hydrology, Runoff, Transpiration, Vegetation, CO₂ Effect, Convective Boundary-Layer, Climate-Change, Carbon Balance, Land-Use, Biosphere Model, Continental-Scale, Ecosystem Models, Energy-Balance, United-States, Part II

Notes: highly cited

? Lehner, B. and Döll, P. (2004), Development and validation of a global database of lakes, reservoirs and wetlands. Journal of Hydrology, 296 (1-4), 1-22.

Full Text: 2004\J Hyd296, 1.pdf

Abstract: Drawing upon a variety of existing maps, data and information, a new Global Lakes and Wetlands Database (GLWD) has been created. The combination of best available sources for lakes and wetlands on a global scale (1: 1 to 1:3 million resolution), and the application of Geographic Information System (GIS) functionality enabled the generation of a database which focuses in three coordinated levels on (1) large lakes and reservoirs, (2) smaller water bodies, and (3) wetlands. Level 1 comprises the shoreline polygons of the 3067 largest lakes (surface area greater than or equal to50 km(2)) and 654 largest reservoirs (storage capacity greater than or equal to0.5 km(3)) worldwide, and offers extensive attribute data. Level 2 contains the shoreline polygons of approx. 250,000 smaller lakes, reservoirs and rivers (surface area; greater than or equal to0.1 km(2)), excluding all water bodies of level 1. Finally, level 3 represents lakes, reservoirs, rivers, and different wetland types in the form of a global raster map at 30-second resolution, including all water bodies of levels 1 and 2.

In a validation against documented data, GLWD proved to represent a comprehensive database of global lakes 1 km(2) and to provide a good representation of the maximum global wetland extent. GLWD-1 and GLWD-2 establish two global polygon maps to which existing lake registers, compilations or remote sensing data can be linked in order to allow for further analyses in a GIS environment. GLWD-3 may serve as an estimate of wetland extents for global hydrology and climatology models, or to identify large-scale wetland distributions and important wetland complexes. (C) 2004 Elsevier B.V. All rights reserved.

Keywords: Lakes, Reservoirs, Wetlands, Global, Geographic Information System, Land Cover Maps, Cover Characteristics Database, Availability, Discover, Model

Notes: highly cited

? Beven, K. (2006), A manifesto for the equifinality thesis. Journal of Hydrology, 320 (1-2), 18-36.

Full Text: 2006\J Hyd320, 18.pdf

Abstract: This essay discusses some of the issues involved in the identification and predictions of hydrological models given some calibration data. The reasons for the incompleteness of traditional calibration methods are discussed. The argument is made that the potential for multiple acceptable models as representations of hydrological and other environmental systems (the equifinality thesis) should be given more serious consideration than hitherto. It proposes some techniques for an extended GLUE methodology to make it more rigorous and outlines some of the research issues still to be resolved. (c) 2005 Elsevier Ltd All rights reserved.

Keywords: Equifinality, Glue, Hydrological Models, Observation Error, Fuzzy Measures, Uncertainty, Uncertainty Estimation, Climate-Change, Monte-Carlo, Environmental Systems, Parameter Uncertainty, Global Optimization, Model Uncertainty, Hydrologic-Models, Catchment Models, Glue Methodology