Showing papers in "Advances in Water Resources in 2003"

TL;DR: In this article, an incompressible smoothed particle hydrodynamics (SPH) method is presented to simulate Newtonian and non-Newtonian flows with free surfaces.

TL;DR: A consistent framework for parameter estimation in distributed hydrological catchment modelling using automatic calibration is formulated, and the balanced Pareto optimum solution corresponding to a proposed balanced aggregated objective function is seen to provide a proper balance between the two objectives.

TL;DR: In this article, an Ensemble Kalman Filter (EnKF) is used to assimilate airborne measurements of 1.4 GHz surface brightness temperature acquired during the 1997 Southern Great Plains Hydrology Experiment (SGP97) into the TOPMODEL-based Land-Atmosphere Transfer Scheme (TOPLATS).

TL;DR: In this paper, a new technique for generating coarse scale models of highly heterogeneous subsurface formations is developed and applied, which uses generic global coarse scale simulations to determine the boundary conditions for the local calculation of upscaled properties (permeability or transmissibility).

TL;DR: In this paper, the wavelet transform is used to detect local singularities in the pressure time history due to the presence of a leak, which reveals the arrival time of the reflected pressure wave and is the basis for leak location.

TL;DR: In this paper, the influence of soil moisture dynamics on soil carbon and nitrogen cycles is analyzed by coupling an existing stochastic soil moisture model [Adv. Water Resour. 24 (7) (2001) 707; Proc. R. Soc. A 455 (1999) 3789] to a system of eight nonlinear differential equations that describe the temporal evolution of the organic matter and the mineral nitrogen in the soil at the daily to seasonal time scales.

TL;DR: Despite the drought in this bottomland forest accustomed to ample water supply, maximum daily transpiration and growing season transpiration were similar to a nearby upland forest measured during a year of above average precipitation.

TL;DR: In this paper, the authors compare the results of a stream tracer and a model that admits a general residence time distribution (RTD), called solute transport and multirate mass transfer-linear coordinates (STAMMT-L).

TL;DR: In this article, an accurate representation of the hydrological mechanisms that control the nitrogen cycle at the daily time scale is shown to be necessary to capture the impact of the highfrequency variability of the soil moisture on the nitrogen and carbon dynamics.

TL;DR: Details of a Galerkin finite-element model for the simulation of density-dependent, variably saturated flow processes are presented here, and it is shown that the Elder salt-convection problem is more suited to the model testing process than the Henry salt-water intrusion problem.

TL;DR: In this article, the authors address the question of whether remotely sensed latent heat flux estimates over a catchment can be used to improve distributed hydrological model water balance computations by the process of data assimilation.

TL;DR: In this paper, the convergence rate of the iterative split-operator (ISO) approach for solving nonlinear reactive transport problems is investigated. But the convergence performance of the ISO algorithm is not analyzed.

TL;DR: In this paper, a new higher-order solution to the nonlinear boundary value problem is derived, which demonstrates the significant influence of the higher order components and beach slope on the water table fluctuations.

TL;DR: In this article, the authors used the Darcy-Weisbach friction factor as a predictor variable for predicting the response of hydrologic retention in streams to major adjustments in channel morphology as well as changes in streamflow.

TL;DR: Predicting the mean sediment loads from experimental runs, the performance of the fuzzy model was compared with that of the artificial neural networks (ANNs) and the physics-based models and revealed that the fuzzy models performed better under very high rainfall intensities over different slopes and over very steep slopes under different rainfall intensITIES.

TL;DR: In this paper, a set of coupled analytical models for the seasonality and annual water balance of catchments were developed and demonstrated, while assuming that climate, soil and vegetation are effectively uniform over the catchment.

TL;DR: In this paper, Nitrification and denitrification kinetics in sediment perfusion cores were numerically modeled and compared to experiments on cores from the Shingobee River MN, USA.

TL;DR: The hyporheic zone is defined as the porous areas of the stream bed and stream bank in which stream water mixes with shallow groundwater as discussed by the authors, and it is a mixing zone in which there are gradients in the concentrations of dissolved gasses, concentrations of oxidized and reduced species, pH, and temperature.

TL;DR: In this paper, a numerical model for unsaturated moisture transport in fractured porous media is developed, which combines a discrete fracture model for moisture flow in a variable aperture fracture with a finite element model of unsaturated flow in the porous matrix.

TL;DR: In this article, the authors compare solute transport and hyporheic exchange in vegetated and unvegetated reaches of Sava Brook, an agricultural stream in Sweden subject to extreme variations in channel vegetation and morphology due to both natural seasonal effects and anthropogenic manipulation.

TL;DR: In this article, high-resolution radar rainfall fields and a distributed hydrologic model are combined for analysis and monitoring of extreme floods, including the Rapidan River flood of 1995.

TL;DR: Four finite-volume component-wise total variation diminishing (TVD) schemes, including the Liou–Steffen splitting (LSS), van Leer splitting, Steger–Warming splitting and local Lax–Friedrichs splitting schemes, are developed and demonstrated that the LSS scheme has the best numerical accuracy among the schemes tested.

TL;DR: Nudging is shown to be successful in improving the hydrological simulation results, and it introduces little computational cost, in terms of CPU and other numerical aspects of the model’s behavior, in some cases even improving numerical performance compared to model runs without nudging.

TL;DR: Sodium bromide and Rhodamine WT were used as conservative tracers to examine the hydrologic characteristics of seven tundra streams in Arctic Alaska, during the summers of 1994-1996 as mentioned in this paper.

TL;DR: In this paper, the authors discuss the development and implications of unsaturated flow beneath the streambed and propose an approximate solution to estimate aquifer drawdown and stream depletion under saturated/unsaturated hyporheic zone flow conditions.

TL;DR: The regression partitioning method (RPM) as discussed by the authors is a technique for analyzing solute addition data in which whole stream uptake (mg m 2 d � 1 ) is determined from the longitudinal pattern in plateau tracer concentrations.

TL;DR: In this article, a special issue of Advances in Water Resources presents recent progress in the application of data assimilation for distributed hydrological modeling and in the use of in situ and remote sensing datasets.

TL;DR: This work forms the two spatial discretizations within a MOL context for the pressure head form of RE as well as a fully mass-conservative version, and compares the higher order, adaptive time discretization to a first-order approximation with formal error control and adaptive time step selection.

TL;DR: In this article, a Jarvis-based canopy conductance model was used to simulate canopy transpiration (EC) for five tree species from upland and wetland locations in Wisconsin.

TL;DR: In this article, the authors examined the hydraulics and hydrology of flood response in the Charlotte, North Carolina metropolitan area through a combination of numerical modeling studies and diagnostic analyses of paired discharge observations from upstream-downstream gaging stations.